Bank protection construction method for improving flood prevention capacity of river middle-upstream dike

Abstract

The invention provides a bank protection construction method for improving flood control capacity of river middle and upstream dikes, which belongs to the technical field of bank protection construction and comprises the following steps: step 1, classifying bank protection structures for flood control of river middle and upstream dikes and adapting to corresponding construction processes; 2, a multi-dimensional coordinate linkage system is constructed for the bank protection structure for flood control of the river middle-upstream dike; 3, a pile foundation construction optimization process is executed on the revetment structure for flood control of the river middle-upstream dike; 4, a cofferdam and temporary flood control wall technology is executed on the revetment structure used for flood control of the river middle-upstream dike; and 5, the construction process is executed on the bank protection structure for flood control of the river middle-upstream dike. Flood prevention safety during construction is ensured; efficient pile foundation construction equipment and a cofferdam anti-seepage technology are integrated, the construction efficiency and the engineering quality are improved, and meanwhile the influence on the ecological environment of the river channel is reduced.

Description

Technical Field

[0001] This invention belongs to the field of bank protection construction technology, specifically relating to a bank protection construction method for improving the flood control capacity of embankments in the middle and upper reaches of rivers. Background Technology

[0002] As vital water conservancy channels, the stability of the flood control system of rivers directly impacts the safety of life and property of residents along their banks and regional economic development. With the increasing frequency of extreme weather events and rising demands for river navigation, existing dikes present numerous problems: old retaining wall structures are aging, and some sections lack sufficient flood control standards to withstand 100-year high water levels; traditional bank protection construction methods, such as those mentioned in patent publication number "CN118273270A," often employ a single structural form, making it difficult to adapt to the diverse geological conditions (such as complex soil layers like grayish-yellow silty clay and silty clay) and functional requirements (flood control, navigation, and landscaping) of different riverbank sections in the middle and upper reaches; a chaotic coordinate system during construction leads to accumulated errors between different measurement control points, resulting in insufficient accuracy in pile positioning and retaining wall pouring; furthermore, poor coordination between flood season and non-flood season construction, coupled with poor compatibility between temporary flood control measures and the main structure, easily triggers flood control safety hazards during construction.

[0003] Existing bank protection construction technologies have the following limitations: First, pile foundation construction often uses single equipment, such as vibratory hammers or static pressure pile drivers, which are not adaptable to complex conditions such as rock dumping areas on water or narrow land sites, resulting in low pile driving efficiency and large deviations in pile verticality. Second, the cofferdam construction process has not been optimized in accordance with the hydrological characteristics of rivers, resulting in poor seepage prevention and incomplete dredging after demolition, which easily pollutes the river channel. Third, there is a lack of standardized construction procedures for various types of bank protection (vertical, landscape, and ecological composite grass slope types, etc.), making settlement and leakage problems prone to occur at the joints of various structures. Fourth, the coordinate linkage mechanism is lacking, and the measurement control network is not deeply integrated with the zero-point elevation system of the bank protection, resulting in insufficient structural connection accuracy between different construction sections (such as R5 and R6 sections), affecting the overall flood control performance.

[0004] Therefore, there is an urgent need for a bank protection construction method that is adaptable to the complex working conditions in the middle and upper reaches of rivers, takes into account both flood control and ecological landscape needs, and has a high-precision coordinate linkage mechanism, in order to solve the problems of poor structural adaptability, low construction accuracy, and poor connection with flood control in existing technologies. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a method for constructing revetments to enhance the flood control capacity of levees in the middle and upper reaches of rivers, achieving the following objectives: adapting to 22 types of revetment structures across 5 categories to meet the flood control, navigation, and landscape functional requirements of different river sections; establishing a multi-dimensional coordinate linkage system to reduce measurement errors and improve the accuracy of pile positioning and retaining wall pouring; optimizing the construction process between flood season and non-flood season to ensure flood control safety during construction; and integrating efficient pile foundation construction equipment with cofferdam seepage prevention technology to improve construction efficiency and project quality while reducing the impact on the river's ecological environment.

[0006] The present invention employs the following technical solution.

[0007] A method for constructing revetments to enhance the flood control capacity of levees in the middle and upper reaches of rivers includes:

[0008] Step 1: Classify and adapt the revetment structures used for flood control in the middle and upper reaches of rivers to the appropriate construction techniques;

[0009] Step 2: Construct a multi-dimensional coordinate linkage system for the revetment structure used for flood control in the middle and upper reaches of rivers;

[0010] Step 3: Implement optimized pile foundation construction technology for revetment structures used for flood control in the middle and upper reaches of rivers;

[0011] Step 4: Implement cofferdam and temporary flood control wall construction techniques for the revetment structures used for flood control in the middle and upper reaches of rivers;

[0012] Step 5: Implement the construction process for the revetment structure used for flood control in the middle and upper reaches of rivers.

[0013] Furthermore, step 1 specifically includes:

[0014] Based on the geological conditions or functional requirements of the R5 and R6 sections in the middle and upper reaches of rivers, the revetment structures used for flood control in the middle and upper reaches of rivers are divided into five major categories: V-type, P-type, E-type, T-type, or W-type revetment structures, and specific construction techniques are formulated for each type of revetment structure.

[0015] Furthermore, in step 1, the method for developing specific construction techniques for each type of revetment structure is as follows:

[0016] V-shaped revetment structure: Its construction process is to construct a vertical flood control wall, which is divided into two categories: renovation and new construction. For renovation, 0.2m of the old retaining wall needs to be removed first, and the height needs to be extended by 0.9m to the design top elevation (0.20m of the revetment zero point), and the flood control wall handrail needs to be installed. For new construction, PU600×218.5×15.4×15m U-shaped steel sheet piles are driven in the front row, and φ600mm@1.8m, 15m long cast-in-place piles are driven in the rear row. After the old retaining wall is removed, the new wall is poured using a molding template.

[0017] P-type revetment: Its construction process is to construct a landscape-type flood control wall. It consists of a primary retaining wall, a secondary retaining wall, and a hardened structure. A patrol walkway is provided. The front row is constructed with PU600×218.5×15.4×21m U-shaped steel sheet piles, and the rear row is constructed with φ600mm@1.8m cast-in-place piles with a pile length of 18m. An ecological hollow box is set behind the primary retaining wall, and a 5m wide road and A-type drainage ditch are set behind the secondary retaining wall.

[0018] Type E revetment: Its construction process is to construct an ecological compound grass slope. The first retaining wall is made of ecological blocks, and behind the wall is a compound grass slope. The front row is equipped with PU600×218.5×15.4×18m U-shaped steel sheet piles, and the rear row is equipped with 400×400×18m@1.2m concrete square piles. The grass slope is covered with soil and water conservation blankets and 300mm thick topsoil.

[0019] T-shaped revetment: Its construction process is to construct a flower bed-shaped double flood control wall. Its flood control road is lower than the secondary wall. Behind the bank is woodland. The front row is driven with PU600×218.5×15.4×21m U-shaped steel sheet piles, and the rear row is driven with φ600mm@1.8m, 21m long cast-in-place piles. The secondary retaining wall adopts a shaped template, and a B-type drainage ditch is set behind the wall.

[0020] W-type revetment: Its construction process is to construct a wetland-type flood control wall. In front of the wall is a beach. PU600×218.5×15.4×12m U-shaped steel sheet piles are driven at the beach protection line. After the old retaining wall is removed and raised, a 5m wide road and grass ditch are set behind the wall.

[0021] Furthermore, in step 1, the method for dividing the R5 and R6 segments in the middle and upper reaches of the river is to use the center line of the river channel in the middle and upper reaches of the river as the boundary between the R5 and R6 segments.

[0022] Furthermore, step 2 specifically includes:

[0023] Step 2-1: Establish a baseline control network;

[0024] Step 2-2: Perform coordinate linkage calculation;

[0025] Steps 2-3: Perform dynamic error correction.

[0026] Furthermore, step 2-1 specifically includes:

[0027] Based on the plane control points and zero elevation of the revetment structure for flood control in the middle and upper reaches of the river provided by the owner, a three-level control network consisting of a primary network, a secondary network, and a tertiary network is set up using a total station: the primary network covers the entire R5 and R6 segments, the secondary network is divided according to the construction sections of the R5 and R6 segments, and the tertiary network is for local control of individual structures. Each control point of the local control is protected by a concrete pier, and a forced centering device is embedded in the top of the concrete pier.

[0028] Furthermore, step 2-2 includes:

[0029] A plane coordinate-elevation-pile location linkage model was established. The plane coordinates adopted the Gauss projection 3° zone, and the elevation was uniformly adopted from the revetment zero point. Before construction, each control point was checked by GPS-RTK. If the error exceeded ±5mm, it was recalibrated. When laying out the pile locations, the polar coordinate method was used in combination with total station resection. The X coordinate, Y coordinate and elevation of the pile locations were recorded and compared with the design values. If the deviation exceeded ±10mm, adjustments were made.

[0030] Furthermore, step 2-2 specifically includes:

[0031] The Trimble R10 GPS receiver was used, equipped with a dedicated base station and rover station, and the equipment calibration was completed in advance.

[0032] Select a known high-level control point (as a reference station), set up a tripod, and accurately center and level it;

[0033] Next, configure the parameters of the Trimble R10 GPS receiver:

[0034] Coordinate system: Gaussian projection 3° zone;

[0035] Elevation system: bank protection zero point;

[0036] Sampling interval: 1 second;

[0037] Observation time: 5 minutes of static observation at each point;

[0038] Then, the Trimble R10 GPS receiver was used to measure the control points of each secondary network and the control points of the tertiary network point by point. 20 sets of data were collected for each point, and the average value of each set of data was calculated as the measured coordinates.

[0039] When the absolute value of the difference between the measured coordinates and the design coordinates (ΔX, ΔY, or ΔH) exceeds ±5mm, first check whether the base station is stable, the satellite signal, and the surrounding environment.

[0040] After eliminating external interference, the control point is measured three times independently. If all three results are out of tolerance, the control point displacement or the initial data is incorrect.

[0041] If a single control point is out of tolerance, the coordinates of that point are recalculated using the triangulation adjustment method with three surrounding qualified control points.

[0042] If two or more consecutive control points exceed the tolerance, the control network for the area should be re-established, and the least squares method should be used for overall adjustment.

[0043] The closure error should be ≤ ±2 when measuring from the starting point to the ending point and back to the starting point. mm;

[0044] The corrected control points must be reviewed and signed by the supervision unit before they can be used for subsequent construction.

[0045] Then a Leica TS60 total station was used, equipped with a 2m prism pole;

[0046] Select 2-3 control points that have been verified and approved near the pile locations to be laid out;

[0047] Input the coordinates of the control points, and the total station will automatically calculate the station coordinates and check the intersection accuracy.

[0048] If the accuracy is not met, increase the number of control points and re-intercept;

[0049] Input the X coordinates, Y coordinates, and elevation of the designed pile location;

[0050] The total station calculates the layout angle and distance, and directs the prism to move to the theoretical position;

[0051] Repeatedly adjust the prism position until the difference between the measured coordinates and the design coordinates is ≤ ±5mm;

[0052] Measure the elevation of the pile location using a total station and compare it with the design elevation;

[0053] The measured X-coordinate, Y-coordinate, and elevation are recorded electronically, and the deviations ΔX, ΔY, and ΔH obtained by subtracting them from the design values ​​are automatically calculated.

[0054] When any value of |ΔX|, |ΔY|, or |ΔH| exceeds ±10mm, stop the layout and analyze the reason:

[0055] If the error is due to measurement error, rebuild the station and set out again;

[0056] If it is a systematic error, trace back to the control point verification process and recalibrate.

[0057] Planar position adjustment: Obtain the same adjustment amount based on ΔX and ΔY, mark the new position on the ground with a small steel ruler, and measure and verify again until the deviation is ≤ ±10mm;

[0058] Elevation adjustment: If it is a pile foundation, adjust the height of the casing or the drilling depth; if it is a precast pile, adjust the driving depth of the pile.

[0059] Overall deviation of pile group: When the deviation of three or more consecutive piles exceeds the limit, the control network should be re-inspected and the local control network should be re-laid if necessary.

[0060] Considering the effects of water flow and tides, a dynamic stakeout method was adopted, with measurements repeated every 5 minutes, and the average value was taken as the final location.

[0061] Pile locations adjacent to existing structures: When adjustments may affect existing structures, a special adjustment plan shall be prepared and submitted to the design unit for approval.

[0062] After the adjusted pile positions are deemed acceptable, they must be inspected and accepted by the supervising engineer, and the "Pile Position Layout Acceptance Record Form" must be signed before pile foundation construction can proceed.

[0063] Furthermore, steps 2-3 include:

[0064] In the key processes of pile driving and retaining wall pouring for the revetment structure, after every 10 piles or 20m of retaining wall are constructed, the adjacent control points are re-measured, and the cumulative error is corrected using the least squares method. For the construction section on the water, considering the influence of water flow and tide on the measurement, a dynamic positioning method is adopted to compensate for the error caused by the swaying of the ship in real time, ensuring that the pile position deviation is ≤±15mm.

[0065] Furthermore, steps 2-3 specifically include:

[0066] After every 10 piles are completed, the adjacent 2-3 tertiary control points of the construction section are immediately re-measured; retaining wall pouring process: after every 20m of retaining wall is poured, 3 secondary or tertiary control points corresponding to the two ends and the middle of the retaining wall are selected as re-measurement objects to ensure coverage of the current construction area;

[0067] It uses a Leica TS60 total station, equipped with a 2m centering rod and temperature and pressure sensors;

[0068] A Leica TS60 total station was set up at the starting control point of the re-measurement. After centering and leveling, the Leica TS60 total station was allowed to stand for 10 minutes to stabilize its temperature. The design coordinates of the control point were input, and the measurement mode was set to "corner-side joint measurement". Temperature data was collected simultaneously. air pressure The data is used for distance measurement correction;

[0069] Three rounds of observations were conducted on the target control point. Each round included measurements of the horizontal angle, vertical angle, and slope distance. The horizontal angle observation adopted the full-circle direction method, with a half-measurement regression zero error ≤6″ and an inter-round difference ≤9″. The slope distance observation required meteorological correction, with a distance difference of ≤2mm per round.

[0070] Electronic handbooks were used to record data, and the measured coordinates of control points for each round of measurement were automatically calculated. The average value of the three rounds of data was taken as the final measured value. The observation time, meteorological conditions and instrument status were also marked.

[0071] Calculate the difference between the measured coordinates and the design coordinates of the re-measured control points. , , If the absolute value of any difference exceeds ±5mm, it is determined that there is a cumulative error and the correction process needs to be initiated.

[0072] After initiating the correction process, take all the re-measured control points (set as n, n≥3) within the current construction section as the observation objects and establish the error equation: V=AX−L, where: V is the observation value correction vector; A is the coefficient matrix; X is the control point coordinate correction vector to be determined; L is the difference vector between the observation value and the design value;

[0073] Based on the principle of least squares, solve for the coordinate correction vector: X = , where P is the weight matrix, which is assigned a value according to the observation accuracy;

[0074] Implementation and Verification:

[0075] Calculate the coordinate corrections for each control point and correct the original design coordinates accordingly.

[0076] , , ;

[0077] After correction, re-measure the control points to verify whether the corrected coordinate deviation is ≤ ±5mm; if it is still out of tolerance, check the rationality of the error equation construction and recalculate until the accuracy requirements are met.

[0078] The corrected control point coordinates were entered into the construction surveying system for the construction of the revetment structure for flood control of the middle and upper reaches of the river, serving as the benchmark for the subsequent construction of 10 piles / 20m retaining walls.

[0079] Next, a Trimble R10 GNSS receiver was used, paired with an IMU inertial measurement unit; the base station was set up at a stable control point on shore, and the rover station was installed on top of the bridge of the piling vessel to ensure that the antenna height was fixed.

[0080] Equipped with a shipborne data processing terminal, it receives GNSS and IMU data in real time, with a sampling interval of 1Hz to ensure data transmission delay ≤0.5 seconds;

[0081] In calm waters where the revetment structure is located, the piling vessel is fixed in place. Three known coordinate points on the hull deck are measured using a total station and compared with the hull attitude output by the GNSS+IMU. The initial attitude deviation of the IMU is corrected to ensure that the attitude measurement error is ≤ ±0.05°.

[0082] Transformation parameters from the WGS84 geodetic coordinate system to the engineering plane coordinate system were established. The 7-parameter transformation method was adopted, and the transformation parameters were calculated using GNSS observation data from 3 known plane control points on the shore. The transformation residual was ≤ ±3mm.

[0083] Real-time water flow velocity and tidal level changes in the middle and upper reaches of the river during the construction period were obtained from hydrological stations along the river to establish the effect of water flow on the lateral displacement of the ship. Impact Model:

[0084] , Changes in ship elevation caused by tides are directly compensated for in real time using water level data. ;

[0085] The IMU acquires the ship's roll angle α and pitch angle β in real time, and calculates the positional deviation of the pile location layout points: , Meanwhile, the hull sway amplitude is determined by the standard deviation σ of GNSS data. When σ > 5mm, the dynamic compensation algorithm is activated.

[0086] After activating the dynamic compensation algorithm, the shipborne terminal fuses GNSS position coordinate data and IMU attitude data in real time, and uses a Kalman filter algorithm to remove outlier data, thereby outputting the filtered real-time position coordinate data of the ship. ;

[0087] Based on the established error model, calculate each error component ( , , , , The filtered position data coordinates are then corrected.

[0088] ;

[0089] The compensated pile coordinates ( ) and design coordinates Real-time comparison is performed to calculate the deviation value. , , The driver issues adjustment instructions to the operator via the display screen in the cab, and the pile driving operation can only begin when the deviation value is ≤ ±15mm.

[0090] Furthermore, step 3 specifically includes:

[0091] Equipment selection and adaptation: The equipment is selected according to the construction scenario. The water pile driving section adopts a hydraulic backhoe dredging and pile driving vessel, combined with a static pressure pile driver. After dredging, the piles are driven, with an efficiency of 25 piles / shift. The land pile driving section adopts a combination of ZX690lCH-5A vibratory hammer and static pressure pile driver. In narrow sites, a 25t truck crane is used to feed the piles.

[0092] Pile foundation quality control: Steel sheet piles need to be sandblasted to remove rust before entering the site, and anti-corrosion treatment should be carried out 5m below the pile top; Drilled cast-in-place piles are constructed using GPS-10 drilling rigs with positive circulation, mud density is controlled at 1.1-1.3g / cm³, sand content ≤4%, sediment thickness after cleaning ≤50mm, reinforcement cage protective layer deviation ±20mm, underwater concrete pouring guide pipe burial depth 2-5m, and over-pouring at the pile top ≥1m;

[0093] Construction of imitation wood piles and precast square piles: The number of layers of imitation wood piles shall be ≤8, and the exterior shall be painted before installation; the precast square piles shall be positioned by a limiting frame, and the verticality shall be observed in both directions by a theodolite during pile driving, with a deviation of ≤0.5%, and the pile hole shall be backfilled with ballast in a timely manner after the pile is driven.

[0094] Furthermore, step 4 specifically includes:

[0095] The cofferdam design is phased: the cofferdam structure remains the same during the flood season and the non-flood season, with only the pile length adjusted. During the flood season, the double-row steel sheet piles are 15m long, while during the non-flood season, they are 12m long; the single-row combined piles are 18m long during the flood season and 15m long during the non-flood season. The cofferdam is constructed in sections, with self-propelled barges equipped with ZX480H-3 vibratory manipulators for pile driving on the water, and a pile driving vessel is provided for material turnover.

[0096] Seepage prevention and drainage optimization: a seepage-proof geomembrane and a filter geotextile are laid on the inner side of the cofferdam. The backfill soil inside the cofferdam is silty clay with a low permeability coefficient and is backfilled in layers. The initial drainage is controlled according to the daily precipitation ≤50cm. A water collection well is set up and equipped with 3 4-inch submersible pumps. Light wellpoint dewatering is used during the bank protection construction period. Drainage ditches and water collection wells are set up around the foundation pit to ensure dry construction.

[0097] Temporary flood control wall connection: Temporary flood control wall two is used during the flood season, and temporary flood control wall three is used during the non-flood season; before the old retaining wall is demolished, the temporary flood control wall is constructed first, and the connection with the main structure is reinforced with steel bars to ensure flood control closure. During demolition, the process is as follows: water release → removal of tie rods → excavation → pile extraction → dredging. The excavated soil is transported to the next section or spoil disposal site by dredger.

[0098] Furthermore, step 5 specifically includes:

[0099] Overall process: Construction preparation → pile foundation construction → construction according to the appropriate revetment structure construction technology → road construction → drainage construction → flood control house construction → landscaping → ancillary facilities → final acceptance.

[0100] Key process control: old retaining walls are demolished using hydraulic breakers, and the rebar depth is ≥15d when the base plate is retained. New retaining walls are poured using standardized steel formwork, vibrated to ensure compaction, and cured for ≥14d. Before installing ecological blocks, the foundation must be leveled, and gaps must be filled with cement mortar. The compound grass slope is trimmed at a slope of 1:1.5, and the compaction degree of the planting soil is ≥85%.

[0101] The beneficial effects of the present invention are as follows, compared with the prior art:

[0102] Improved structural adaptability: Through specialized processes of 22 types of bank protection structures in 5 categories, it adapts to the geological (such as silty soil layers and riprap areas) and functional requirements of different bank sections in the middle and upper reaches of rivers. The vertical structure meets the high flood control standard (100-year high water level of 5.44m), the ecological structure enhances the ecological landscape of the river, and the landscape structure takes into account the needs of inspection and navigation.

[0103] Improved construction accuracy: The multi-dimensional coordinate linkage system controls the pile position deviation within ±15mm, the retaining wall axis deviation ≤±10mm, and the elevation deviation ≤±5mm. This solves the problems of coordinate confusion and error accumulation in traditional construction, ensuring that the structure of each section (R5, R6) is closely connected and improving the overall flood control performance.

[0104] Enhanced flood control safety: The phased construction of cofferdams and temporary flood walls allows for seamless integration of construction during the flood season and non-flood season. The cofferdams achieve a seepage prevention rate of over 98%, and the temporary flood walls meet the protection requirements for the highest navigable water level of 4.80m, avoiding the risk of river backflow during construction.

[0105] Construction efficiency and environmental friendliness are optimized: the pile foundation construction equipment is adapted to different scenarios, with a pile driving efficiency of 25 piles / shift on water and 30 piles / shift on land, which is 30% higher than the traditional process; the mud is dried (the dried soil is backfilled after meeting the standards, and the tailwater is reused), and the anti-corrosion treatment of steel sheet piles reduces river pollution and meets the environmental protection requirements of Shanghai. Attached Figure Description

[0106] Figure 1 This is a flowchart of the revetment construction method for improving the flood control capacity of embankments in the middle and upper reaches of rivers in this invention. Detailed Implementation

[0107] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of this invention. The embodiments described in this application are merely some embodiments of this invention, and not all embodiments. Based on the spirit of this invention, other embodiments obtained by those skilled in the art without creative effort are all within the protection scope of this invention.

[0108] like Figure 1 As shown, a method for constructing revetments to enhance the flood control capacity of levees in the middle and upper reaches of rivers includes:

[0109] Step 1: Classify and adapt the revetment structures used for flood control in the middle and upper reaches of rivers to the appropriate construction techniques;

[0110] In a preferred but non-limiting embodiment of the present invention, step 1 specifically includes:

[0111] Based on the geological conditions (such as mud surface elevation and soil layer distribution) or functional requirements of the R5 and R6 sections in the middle and upper reaches of rivers, the revetment structures used for flood control in the middle and upper reaches of rivers are divided into five major categories: V-type (vertical), P-type (landscape type), E-type (ecological duplex grass slope type), T-type (flower bed duplex), or W-type (wetland type). Specific construction techniques are developed for each type of revetment structure.

[0112] In step 1, based on the geological conditions (such as mud surface elevation and soil layer distribution) or functional requirements of the R5 and R6 sections in the middle and upper reaches of the river, the method for classifying revetment structures used for flood control in the middle and upper reaches of the river into five categories: V-type (vertical), P-type (landscape type), E-type (ecological duplex grass slope type), T-type (flower bed duplex), or W-type (wetland type) revetment structures includes:

[0113] The classification method based on the geological conditions (such as mud surface elevation and soil layer distribution) of the R5 and R6 segments in the middle and upper reaches of rivers can be as follows:

[0114] 1. High mud surface section (design mud surface -2.82~-4.40m)

[0115] Geological characteristics: The mud surface is shallow, and the lower part is mostly grayish-yellow silty clay (bearing capacity characteristic value fak=180kPa). The soil layer has good stability and does not require ultra-long pile foundations.

[0116] Compatible revetment structure types:

[0117] V-type (vertical): such as V1C1 type (for modifying old retaining walls, only 0.9m height needs to be added), V4A1-b3 type (400×400×15m square piles in the back row, which can penetrate soft soil layers with a soil depth of 12m), no deep water construction equipment is required, and the efficiency of pile driving on land is high (ZX690lCH-5A vibratory hammer has a capacity of 30 piles / shift).

[0118] W type (wetland type): such as W2C2 type (12m long U-shaped steel sheet piles are driven at the beach protection line. The mud surface is shallow and construction can be carried out directly on land. Large-scale dredging of the beach in front of the wall is not required).

[0119] 2. Medium mud surface section (design mud surface -6.42~-12.10m, distributed in the first sub-section of R6)

[0120] Geological characteristics: The mud surface is of medium thickness, with the upper part being silty clay (fak=120kPa) and the lower part being silty clay (fak=200kPa). 15-18m long piles are required to penetrate the soft soil layer.

[0121] Suitable bank protection types:

[0122] Type E (Ecological Compound Grass Slope): such as E1A1-b3 (front row of 18m long U-shaped steel sheet piles + rear row of 18m square piles, the grass slope's self-weight can enhance the stability of the embankment, suitable for medium bearing capacity soil layers).

[0123] T-type (flower bed type duplex): such as T1B2-d type (19m long U-shaped steel sheet piles, secondary retaining wall uses shaped template, the load of the woodland behind the wall is small, and there is no need for ultra-deep pile foundation).

[0124] 3. Low mud level section (design mud level -15.10~-21.10m)

[0125] Geological characteristics: The mud surface is deep, and the entire cross section is silty clay (fak=100kPa). 21-24m long pile foundations are required to ensure bearing capacity, and dredging work on water is also required.

[0126] Suitable bank protection types:

[0127] V-type (vertical): such as V1A1-b2 type (24m long U-shaped steel sheet pile + 24m cast-in-place pile, double pile body to enhance pull-out resistance, suitable for soft soil layer), V4A1-b1 type (21m long U-shaped steel sheet pile + 21m cast-in-place pile, the 4m wide road behind the wall has a large load, and deep piles are required to ensure the stability of the foundation).

[0128] Type P (Landscape Type): such as P2A1-b1 (21m long U-shaped steel sheet piles + 18m cast-in-place piles, with an ecological empty box behind the first-level retaining wall, and the landscape structure installation can be completed simultaneously during construction on water).

[0129] Based on the functional requirements of the R5 and R6 segments in the middle and upper reaches of rivers, the classification method can be as follows:

[0130] V-shaped (vertical) revetment structure: mainly used to meet flood control needs, especially in areas with high flood scouring force. The vertical revetment structure can provide strong scouring and soil retention capabilities, ensuring the safety of the embankment.

[0131] P-type (landscape-type) revetment structure: focuses on landscape function, providing people with places to enjoy the river landscape by setting up patrol trails, ecological empty boxes and other facilities, while also facilitating daily patrol and maintenance of the embankment.

[0132] Type E (Ecological Duplex Grass Slope) bank protection structure: Emphasizing ecological functions, the ecological blocks and duplex grass slopes provide habitats for plants and animals, promote the balance and stability of the ecosystem, and also have a certain flood control capacity.

[0133] T-shaped (flower bed type duplex) revetment structure: It combines landscape and flood control functions. Through unique shape templates and duplex structure design, it creates a beautiful flower bed-style landscape while ensuring the safety of the embankment, thus improving the overall landscape quality of the river.

[0134] W-type (wetland type) revetment structure: mainly serves wetland ecological protection and embankment protection, adapts to the wetland ecological environment, and protects the integrity of the beach and forest ecosystem.

[0135] In a preferred but non-limiting embodiment of the present invention, the method for developing specific construction techniques for each type of revetment structure in step 1 is as follows:

[0136] V-shaped revetment structure: Its construction process is to construct a vertical flood control wall, which is divided into two categories: renovation and new construction. For renovation (such as V1C1 type), 0.2m of the old retaining wall needs to be removed first, and the height needs to be extended by 0.9m to the design top elevation (0.20m of the revetment zero point), and the flood control wall handrail needs to be installed. For new construction (such as V1A1-b1 type), PU600×218.5×15.4×15m U-shaped steel sheet piles are driven in the front row, and φ600mm@1.8m, 15m long cast-in-place piles are driven in the rear row. After the old retaining wall is removed, the new wall is poured using a molding template.

[0137] P-type revetment: Its construction process involves constructing a landscape-style flood control wall, consisting of a primary retaining wall, a secondary retaining wall, and a hardened backing, with a patrol walkway (2.5-4m wide). For example, the P2A1-b1 type has PU600×218.5×15.4×21m U-shaped steel sheet piles in the front row and φ600mm@1.8m, 18m long cast-in-place piles in the back row. An ecological enclosure is installed behind the primary retaining wall, and a 5m wide road and a type A drainage ditch are installed behind the secondary retaining wall.

[0138] Type E revetment: Its construction process is to construct an ecological compound grass slope. The first-level retaining wall is made of ecological blocks, and the back of the wall is a compound grass slope, such as E1A1-b3 type. The front row is driven with PU600×218.5×15.4×18m U-shaped steel sheet piles, and the back row is driven with 400×400×18m@1.2m concrete square piles. The grass slope is covered with soil and water conservation blankets and 300mm thick topsoil.

[0139] T-type revetment: Its construction process involves constructing a flower bed-shaped double-layered flood control wall, with the flood control road lower than the secondary wall, and woodland behind the revetment. For example, the T1A1-b3 type has PU600×218.5×15.4×21m U-shaped steel sheet piles in the front row and φ600mm@1.8m, 21m long cast-in-place piles in the rear row. The secondary retaining wall uses a shaped template, and a B-type drainage ditch is set behind the wall.

[0140] W-type revetment: Its construction process involves constructing a wetland-type flood control wall, with a beach in front of the wall. For example, in the W2C2 type, PU600×218.5×15.4×12m U-shaped steel sheet piles are driven at the beach protection line. After the old retaining wall is removed and raised, a 5m wide road and a grassy ditch are set behind the wall.

[0141] Type A drainage ditch: It usually adopts a rectangular cross section, with a bottom width of 0.50m, a depth of 0.40m, and a wall thickness of 0.24m. The structure is made of M7.5 mortar-grouted bricks and is suitable for scenarios requiring high load-bearing capacity.

[0142] Type B drainage ditch: 0.40m wide at the bottom, 0.30m deep, and 0.12m thick at the wall. It is also constructed with M7.5 mortar-grouted bricks, but with a lighter structure, making it suitable for temporary drainage or areas with limited space.

[0143] In a preferred but non-limiting embodiment of the present invention, in step 1, the method for dividing the R5 and R6 segments in the middle and upper reaches of the river is to use the center line of the river channel in the middle and upper reaches of the river as the dividing boundary between the R5 and R6 segments.

[0144] Step 2: Construct a multi-dimensional coordinate linkage system for the revetment structure used for flood control in the middle and upper reaches of rivers;

[0145] In a preferred but non-limiting embodiment of the present invention, step 2 specifically includes:

[0146] Step 2-1: Establish a baseline control network;

[0147] In a preferred but non-limiting embodiment of the present invention, step 2-1 specifically includes:

[0148] Based on the plane control points and zero elevation of the revetment structure for flood control in the middle and upper reaches of the river provided by the owner, a three-level control network consisting of a primary network, a secondary network, and a tertiary network is established using a total station: the primary network covers the entire R5 and R6 segments; the secondary network is divided according to the construction sections of the R5 and R6 segments (just as the R5 segment includes the first construction section and the R6 segment includes the second and third construction sections); and the tertiary network is for the local control of individual structures (such as revetments every 50m or single piles). Each control point of the local control is protected by a concrete pier, and a forced centering device is embedded in the top of the concrete pier to ensure the stability of the point position.

[0149] Step 2-2: Perform coordinate linkage calculation;

[0150] In a preferred but non-limiting embodiment of the present invention, step 2-2 includes:

[0151] A plane coordinate-elevation-pile location linkage model was established. The plane coordinates adopted the Gauss projection 3° zone (central meridian 121°), and the elevation was uniformly adopted from the revetment zero point. Before construction, each control point was checked by GPS-RTK, and recalibrated when the error exceeded ±5mm. When laying out the pile locations, the polar coordinate method was used in combination with total station resection. The X coordinate, Y coordinate and elevation of the pile locations were recorded and compared with the design values. Adjustment was made when the deviation exceeded ±10mm.

[0152] In a preferred but non-limiting embodiment of the present invention, step 2-2 specifically includes:

[0153] I. GPS-RTK Control Point Verification and Calibration Methods

[0154] 1. Control Point Verification Process

[0155] (1) Equipment preparation: Use Trimble R10 GPS receiver (accuracy: plane ±10mm+1ppm, elevation ±20mm+1ppm), equipped with dedicated base station and rover station, and complete equipment calibration in advance (mandatory calibration once a year, self-inspection once a month).

[0156] (2) Base station setup: Select known high-level control points (such as the plane control points X1=3521200.000 and Y1=512300.000 provided by the owner) as base stations, set up tripods and accurately center and level them (centering error ≤1mm, leveling error ≤30″).

[0157] (3) Next, set the parameters for the Trimble R10 GPS receiver:

[0158] Coordinate system: Gaussian projection 3° zone (central meridian 121°);

[0159] Elevation system: bank protection zero point;

[0160] Sampling interval: 1 second;

[0161] Observation time: 5 minutes of static observation at each point;

[0162] (4) Data acquisition: Then, the Trimble R10 GPS receiver was used to measure the control points of each secondary network and the control points of the tertiary network point by point. 20 sets of data were collected for each point, and the average value of each set of data was calculated as the measured coordinates.

[0163] 2. Correction method when the error exceeds ±5mm

[0164] (1) Error analysis: When the absolute value of the difference between the measured coordinates and the design coordinates, the difference between the horizontal coordinates, the difference between the vertical coordinates, or the difference between the elevation, exceeds ±5mm, first check whether the base station is stable, the satellite signal (signal-to-noise ratio ≥35dB), and the surrounding environment (avoid interference sources such as high-voltage lines and large buildings).

[0165] (2) Remeasurement and verification: After eliminating external interference, the control point is measured three times independently. If the results of all three measurements are out of tolerance, the control point displacement or the initial data is incorrect.

[0166] (3) Correction implementation:

[0167] If a single control point is out of tolerance, the coordinates of that point are recalculated using the triangulation adjustment method with three surrounding qualified control points.

[0168] If two or more consecutive control points exceed the tolerance, the control network for the area should be re-established, and the least squares method should be used for overall adjustment.

[0169] After calibration, closed-loop verification is required: measure from the starting point to the ending point and back to the starting point; the closure error should be ≤ ±2. mm (n is the number of stations);

[0170] (4) Confirmation of results: The corrected control points must be reviewed and signed by the supervision unit before they can be used for subsequent construction;

[0171] II. Pile Location Layout and Deviation Adjustment Methods

[0172] 1. Polar coordinate method combined with total station resection and layout process

[0173] (1) Equipment preparation: Then use a Leica TS60 total station (angle measurement accuracy 0.5″, distance measurement accuracy 1mm+1ppm) equipped with a 2m prism rod (with circular level).

[0174] (2) Rear intersection site construction:

[0175] Select 2-3 control points that have been verified and approved near the pile locations to be laid out;

[0176] Input the coordinates of the control points, and the total station will automatically calculate the station coordinates and check the intersection accuracy (point error ≤ 3mm).

[0177] If the accuracy is not met, increase the number of control points and re-intercept;

[0178] (3) Pile location layout:

[0179] Input the X coordinates, Y coordinates, and elevation of the designed pile location;

[0180] The total station calculates the layout angle and distance, and directs the prism to move to the theoretical position;

[0181] Repeatedly adjust the prism position until the difference between the measured coordinates and the design coordinates is ≤ ±5mm;

[0182] Measure the elevation of the pile location using a total station and compare it with the design elevation;

[0183] (4) Data recording: Electronic recording method is used to record the measured X coordinate, Y coordinate and elevation, and the deviations ΔX, ΔY and ΔH obtained by subtracting the design value are automatically calculated respectively;

[0184] 2. Adjustment method when the deviation exceeds ±10mm

[0185] (1) Deviation classification and processing:

[0186] When any value of |ΔX|, |ΔY|, or |ΔH| exceeds ±10mm, stop the layout and analyze the reason:

[0187] If the error is due to measurement error (such as instrument centering deviation or prism rod tilt), the station should be re-established and the layout should be completed.

[0188] If the error is systematic (such as incorrect control point data), trace back to the control point verification process and recalibrate.

[0189] (2) Specific adjustment measures:

[0190] Planar position adjustment: Obtain the same adjustment amount based on ΔX and ΔY, mark the new position on the ground with a small steel ruler, and measure and verify again until the deviation is ≤ ±10mm;

[0191] Elevation adjustment: If it is a pile foundation, adjust the height of the casing or the drilling depth; if it is a precast pile, adjust the driving depth of the pile.

[0192] Overall deviation of pile group: When the deviation of three or more consecutive piles exceeds the limit, the control network should be re-inspected and the local control network should be re-laid if necessary.

[0193] (3) Handling of special circumstances:

[0194] For water-based stake locations: Considering the effects of water flow and tides, a dynamic stakeout method is adopted, with a re-measurement every 5 minutes, and the average value is taken as the final location;

[0195] Pile locations adjacent to existing structures: When adjustments may affect existing structures, a special adjustment plan shall be prepared and submitted to the design unit for approval.

[0196] (4) Acceptance record: The adjusted pile positions must be accepted by the supervising engineer and the "Pile Position Layout Acceptance Record Form" must be signed before pile foundation construction can proceed;

[0197] III. Quality Control Requirements

[0198] Surveyors must be certified to work and participate in no less than 40 hours of professional training each year;

[0199] Measuring instruments should be sent for inspection according to the prescribed cycle, and parameters such as i-angle and 2C value should be checked before daily use;

[0200] All measurement data are subject to double verification, and the original records are kept for 5 years after the project is completed and accepted.

[0201] Establish a measurement error log, analyze error trends regularly, and perform overall correction when the systematic error exceeds 3mm.

[0202] By using the above methods, the accuracy of construction surveying can be ensured to meet the design requirements, providing a reliable position benchmark for subsequent pile foundation construction, retaining wall pouring and other processes, and ultimately achieving precise connection and overall stability of the revetment structure.

[0203] Steps 2-3: Perform dynamic error correction.

[0204] In a preferred but non-limiting embodiment of the present invention, steps 2-3 include:

[0205] In key processes such as pile driving and retaining wall pouring for revetment structures, adjacent control points are re-measured every 10 piles or 20m of retaining wall constructed, and the cumulative error is corrected using the least squares method. For water-based construction sections (such as apartment construction sections), the influence of water flow and tides on the measurement is considered, and dynamic positioning methods (such as RTK + inertial measurement) are adopted to compensate for the error caused by hull sway in real time, ensuring that the pile position deviation is ≤±15mm.

[0206] In a preferred but non-limiting embodiment of the present invention, steps 2-3 specifically include:

[0207] I. Control Point Re-measurement and Least Squares Error Correction Method for Key Processes in Pile Driving and Retaining Wall Casting

[0208] (I) Preparation and Implementation Process for Retesting

[0209] Retesting period and site selection

[0210] Pile driving process: After every 10 piles are completed (including sheet piles, bored piles, precast square piles, etc.), immediately re-measure the 2-3 adjacent tertiary control points (such as control piers within 50m around the pile group) of the construction section; Retaining wall pouring process: After every 20m of retaining wall is poured (calculated according to the axis length), select 3 secondary or tertiary control points corresponding to the two ends and the middle position of the retaining wall as the objects for re-measurement to ensure coverage of the current construction area;

[0211] The retesting points must meet the principles of "stability and visibility". Priority should be given to concrete forced centering piers (such as the C30 concrete pier mentioned in the document, with a forced centering device embedded in the top), and temporary wooden piles or points that are disturbed by construction should be avoided.

[0212] Equipment and personnel configuration

[0213] The survey was conducted using a Leica TS60 total station (angle accuracy 0.5″, distance accuracy 1mm+1ppm), equipped with a 2m centering rod (with a circular level, accuracy ±0.5mm) and temperature and pressure sensors (for meteorological correction); the survey team consisted of one certified surveying engineer and two support staff to ensure standardized operation.

[0214] Data collection for retesting

[0215] Total station setup: Set up the Leica TS60 total station at the starting control point of the re-measurement. After centering (error ≤ 1mm) and leveling (bubble deviation ≤ 1 division), let it stand for 10 minutes to allow the Leica TS60 total station to stabilize its temperature. Input the design coordinates of the control point, set the measurement mode to "side-angle joint measurement", and simultaneously collect temperature data. (Accurate to 0.1℃), air pressure (Accurate to 1 hPa) Data is used for distance measurement correction;

[0216] Data observation: Three rounds of observations were conducted on the target control point, each round including measurements of horizontal angle, vertical angle, and slope distance; horizontal angle observations used the full-circle direction method, with a half-regression zero error ≤ 6″ and an inter-round difference ≤ 9″; slope distance observations required meteorological correction (formula: ,in For actual measured distance, =1013.25 hPa, =293.15K), the distance difference per measurement cycle is ≤2mm;

[0217] Data recording: Electronic handbook is used for recording. The measured coordinates (X, Y, H) of the control points for each measurement are automatically calculated. The average value of the three measurements is taken as the final measured value. The observation time, meteorological conditions and instrument status are also marked.

[0218] (II) Implementation of Least Squares Accumulated Error Correction

[0219] Error judgment criteria:

[0220] Calculate the difference between the measured coordinates and the design coordinates of the re-measured control points. , , If the absolute value of any difference exceeds ±5mm (consistent with the previous control point verification standard), it is determined that there is a cumulative error and the correction process needs to be initiated.

[0221] Least squares modified model construction:

[0222] After initiating the correction process, all re-measured control points within the current construction section (set as n points, n≥3) are taken as the observation objects, and the error equation is established: V=AX−L, where: V is the vector of observed value corrections (including corrections for horizontal angle, vertical angle, and slope distance); A is the coefficient matrix, determined by the geometric relationship between the control point coordinates and the station position (e.g., the coefficient for horizontal angle observation is the partial derivative of the azimuth angle); X is the vector of control point coordinate corrections to be determined (ΔX1,ΔY1,ΔH1;ΔX2,ΔY2,ΔH2;...); L is the vector of the difference between the observed value and the design value (i.e., the measured value minus the design value);

[0223] Based on the principle of least squares, solve for the coordinate correction vector: X = , where P is the weight matrix, which is assigned a value according to the observation accuracy (e.g., the horizontal angle observation weight is 1 / σ², and σ is the angle measurement error, which is 0.5″).

[0224] Implementation and Verification:

[0225] Calculate the coordinate corrections (ΔXi, ΔYi, ΔHi) for each control point and correct the original design coordinates accordingly.

[0226] , , ;

[0227] After correction, re-measure the control points to verify whether the corrected coordinate deviation is ≤ ±5mm; if it is still out of tolerance, check the rationality of the error equation construction (such as whether meteorological correction or instrument error is omitted), and recalculate until the accuracy requirements are met.

[0228] The corrected coordinates of the control points were entered into the construction surveying system for the construction of the revetment structure for flood control of the middle and upper reaches of the river, serving as the benchmark for the subsequent construction of 10 piles / 20m retaining walls. At the same time, the surveying record ledger was updated, noting the reason for the correction, the time and the calculation process, and reported to the supervision unit for record.

[0229] II. Dynamic Positioning and Error Compensation Methods for Water-Based Construction Sections (Apartment Sections)

[0230] (I) Construction of Dynamic Positioning System

[0231] Equipment selection and configuration:

[0232] Next, a Trimble R10 GNSS receiver (supporting BeiDou, GPS, and GLONASS multi-satellite systems, with dynamic positioning accuracy of ±10mm+1ppm for horizontal positioning and ±20mm+1ppm for vertical positioning) was used, paired with an IMU (attitude measurement accuracy of ±0.1° for roll / pitch and ±0.2° for heading). The base station was set up at a stable control point on shore (such as the control point of the first-level network of the R5 segment, far away from electromagnetic interference sources), and the rover station was installed on the top of the bridge of the piling vessel (such as Zhonggang Engineering 01588) to ensure that the antenna height was fixed (the distance from the antenna phase center to the deck of the ship was measured in advance, accurate to 1mm).

[0233] Equipped with a shipborne data processing terminal (with TrimbleBusinessCenter software installed), it receives GNSS and IMU data in real time, with a sampling interval of 1Hz (i.e., 1 set of data is collected per second), ensuring that the data transmission delay is ≤0.5 seconds (using a 4G industrial router with a signal strength ≥-80dBm).

[0234] System parameter calibration:

[0235] Attitude calibration: In calm waters where the revetment structure is located (wind speed ≤3m / s, wave height ≤0.5m), the piling vessel is fixed, and three known coordinate points on the deck of the vessel are measured using a total station (stainless steel measurement marks are welded onto the deck in advance). The coordinates are compared with the hull attitude (roll, pitch, and heading) output by the GNSS+IMU to correct the initial attitude deviation of the IMU and ensure that the attitude measurement error is ≤±0.05°.

[0236] Coordinate transformation: Establish transformation parameters from the WGS84 geodetic coordinate system to the engineering plane coordinate system (Gauss 3° zone, central meridian 121°) using a 7-parameter transformation method (X translation, Y translation, Z translation, X rotation, Y rotation, Z rotation, scale factor). The transformation parameters are calculated using GNSS observation data from three known plane control points on the shore, with a transformation residual ≤ ±3mm.

[0237] (II) Implementation of Real-Time Error Compensation

[0238] Error source identification and modeling:

[0239] Influence of water flow and tides: Real-time water flow velocity (≤1.5m / s) and tidal level changes (recorded hourly, accurate to 0.01m) in the middle and upper reaches of the river during the construction period were obtained from hydrological stations along the river to establish the effect of water flow on the lateral displacement of the hull. Impact Model:

[0240] (v is the water flow velocity, t is the observation time, and θ is the angle between the water flow direction and the engineering axis.) Changes in ship elevation caused by tides are directly compensated for in real time using water level data. ;

[0241] Influence of hull rolling: The IMU collects the hull's roll angle α and pitch angle β in real time to calculate the positional deviation of the pile location layout points. , (h is the vertical distance from the antenna phase center to the pile location layout point), and at the same time, the hull sway amplitude is determined by the standard deviation σ of the GNSS data. When σ > 5mm, the dynamic compensation algorithm is activated.

[0242] Real-time compensation process:

[0243] Data Fusion: After activating the dynamic compensation algorithm, the shipborne terminal fuses GNSS position coordinate data (X_GNSS, Y_GNSS, H_GNSS) and IMU attitude data (α, β, γ) in real time. Anomalies (such as jumps caused by satellite signal loss, with a threshold set: a single position change > 20mm is considered anomaly) are removed using a Kalman filter algorithm. The filtered real-time ship position coordinate data is then output. ;

[0244] Error compensation calculation: Based on the established error model, calculate each error component ( , , , , The filtered position data coordinates are then corrected.

[0245] ;

[0246] Pile location layout guidance: The coordinates of the compensated pile locations ( ) and design coordinates Real-time comparison is performed to calculate the deviation value. , , The driver issues adjustment instructions (such as "adjust to the left by 5mm" or "adjust forward by 3mm") to the operator through the display screen in the cab until the deviation value is ≤ ±15mm before the pile driving operation can be started.

[0247] Accuracy verification and feedback:

[0248] After each underwater pile is driven, a total station (with onshore control points) is used to perform static measurements on the center position of the pile top (3 rounds of measurement, with a difference of ≤3mm per round). The measured coordinates are compared with the design coordinates to verify whether the pile position deviation is ≤±15mm. If the deviation exceeds the tolerance, the accuracy of the error model is analyzed (e.g., whether the water flow velocity is underestimated), and the model parameters are corrected (e.g., the water flow influence coefficient is adjusted) to ensure the accuracy of subsequent pile positions.

[0249] After the daily construction is completed, the positioning and compensation data of the ship-mounted terminal are exported to generate the "Dynamic Positioning Accuracy Report of Waterborne Piles". The deviation value, compensation amount and hydrological conditions of each pile are recorded to optimize the error compensation strategy for the next day (such as shortening the water level sampling interval to 30 minutes during periods of large tidal changes).

[0250] III. Quality Assurance Measures

[0251] Equipment maintenance: Before each day's construction, check the connection status of the GNSS antenna and IMU sensor, and clean the antenna surface (avoid obstruction); the total station should be calibrated weekly for i-angle and 2C values ​​to ensure instrument accuracy; the dynamic positioning system should be tested for static accuracy monthly (static observation should be conducted at known control points on shore, with a plane deviation ≤ ±3mm).

[0252] Personnel training: Surveyors must undergo specialized training, master the least squares method calculation and the operation of the dynamic positioning system, and pass the assessment before they can be put on the job; piling vessel operators must understand the error compensation principle and be able to accurately adjust the hull position according to the instructions on the display screen.

[0253] Emergency Response: During construction on water, if a sudden strong wind (wind speed > 6m / s) or satellite signal loss (number of GNSS satellites < 5) occurs, immediately stop pile driving and anchor the vessel to a safe area; after conditions are restored, re-measure the control points and recalibrate the system, and resume construction only after confirming that the accuracy meets the requirements.

[0254] Step 3: Implement optimized pile foundation construction technology for revetment structures used for flood control in the middle and upper reaches of rivers;

[0255] In a preferred but non-limiting embodiment of the present invention, step 3 specifically includes:

[0256] Equipment selection and adaptation: Equipment is selected according to the construction scenario. For the water-based pile driving section (rock dumping area), a hydraulic backhoe dredging and pile driving vessel (such as Zhonggang Engineering 01588) is used, combined with a static pressure pile driver (PSG-52 type, maximum pressing force 5200kN). After dredging, piles are driven, with an efficiency of 25 piles / shift. For the land-based pile driving section, a combination of ZX690lCH-5A vibratory hammer (efficiency 30 piles / shift) and static pressure pile driver is used. In narrow sites, a 25t truck crane is used to feed the piles.

[0257] Pile foundation quality control: Steel sheet piles must be sandblasted to remove rust before entering the site (Sa2.5 grade, roughness ≥70μm), and anti-corrosion treatment must be carried out 5m below the pile top (75μm epoxy zinc-rich primer + 300μm epoxy resin paint + 125μm thick-film epoxy paint); Drilled cast-in-place piles are constructed using GPS-10 drilling rig with positive circulation, mud density is controlled at 1.1-1.3g / cm³, sand content ≤4%, sediment thickness after hole cleaning ≤50mm, reinforcement cage protective layer deviation ±20mm, underwater concrete pouring guide pipe burial depth 2-5m, and over-pouring at the pile top ≥1m;

[0258] Construction of imitation wood piles and precast square piles: The number of layers of imitation wood piles shall be ≤8, and the exterior shall be painted before installation; the precast square piles shall be positioned using a limiting frame (made of 300×500 steel with a reserved 0.4×0.4m pile hole), and the verticality shall be observed in both directions with a theodolite during pile driving, with a deviation of ≤0.5%. After the pile is driven, the pile hole shall be backfilled with ballast in a timely manner.

[0259] Step 4: Implement cofferdam and temporary flood control wall construction techniques for the revetment structures used for flood control in the middle and upper reaches of rivers;

[0260] In a preferred but non-limiting embodiment of the present invention, step 4 specifically includes:

[0261] The cofferdam design is phased: the cofferdam structure remains the same during the flood season and the non-flood season, with only the pile length adjusted. During the flood season, the double-row steel sheet piles are 15m long, while during the non-flood season, they are 12m long; the single-row combined piles are 18m long during the flood season and 15m long during the non-flood season. The cofferdam is constructed in sections, with self-propelled barges equipped with ZX480H-3 vibratory manipulators for pile driving on the water, and a pile driving vessel is provided for material turnover.

[0262] Optimization of seepage prevention and drainage: A seepage-proof geomembrane (HDPE material, 1.5mm thick) and a filter geotextile are laid on the inner side of the cofferdam. The backfill soil inside the cofferdam is silty clay with a low permeability coefficient, and backfilling is carried out in layers (layer thickness 500mm, compaction degree ≥93%). Initial drainage is controlled according to the daily precipitation ≤50cm. A water collection well (elevation -0.5m) is set up and equipped with 3 4-inch submersible pumps (1 spare). Lightweight wellpoint dewatering is used during the revetment construction period. Drainage ditches and water collection wells are set up around the foundation pit to ensure dry construction.

[0263] Temporary flood control wall connection: During the flood season, temporary flood control wall two (staggered stacking of bagged soil + plain concrete piling, 400mm high, 1:1 slope) is used, and during the non-flood season, temporary flood control wall three (single row of steel sheet piles + impermeable geomembrane + bagged soil) is used. Before demolishing the old retaining wall, the temporary flood control wall is constructed first, and the connection with the main structure is reinforced with steel bars to ensure flood control closure. During demolition, the process is as follows: water release → removal of tie rods → excavation → pile extraction → dredging. The excavated soil on the water is transported to the next section or spoil disposal site by dredger.

[0264] Step 5: Implement the construction process for the revetment structure used for flood control in the middle and upper reaches of rivers.

[0265] In a preferred but non-limiting embodiment of the present invention, step 5 specifically includes:

[0266] Overall process: Construction preparation is carried out in sequence (e.g., start on May 25th of the same year, complete procedures, site leveling, and handover verification before June 20th) → pile foundation construction → construction according to the construction process of the suitable revetment structure (removal of old retaining wall → rebar installation → pouring of new retaining wall) → road construction (5-6m wide flood control road, base layer compaction degree ≥95%) → drainage construction (Type A / Type B drainage ditch, slope 1.5%) → flood control house construction → landscaping (300mm topsoil + soil and water conservation blanket) → ancillary facilities (navigation warning posts, warning lights every 20m) → final acceptance;

[0267] Key process control: old retaining walls are demolished using hydraulic breakers, and when the base plate is retained, the rebar depth is ≥15d (d is the diameter of the rebar). New retaining walls are poured using standardized steel formwork, and compacted by vibration (vibration time 20-30s). The curing period is ≥14d. Before installing ecological blocks, the foundation must be leveled, and the gaps must be filled with cement mortar. The compound grass slope is trimmed at a slope of 1:1.5, and the compaction degree of the planting soil is ≥85%.

[0268] The following is a specific example of the present invention:

[0269] (I) Project Overview

[0270] This example is Section 5 of the Phase II Flood Control Capacity Improvement Project for the Middle and Upper Reaches of a Certain River, covering Section R5 (0+000~1+266.12) and Section R6 (0+000~NHJY0+098.72, 3+412.12~NZGY0+545.95). The geology is mainly grayish-yellow silty clay (layer thickness 0.17-2.50m) and silty clay (layer thickness 2.50-14.73m). The design flood control standard is once every 100 years, with a maximum navigable water level of 4.80m (zero point of the revetment). The revetment structure includes 15 types such as V1C1, V1A1-b1, P2A1-b1, E1A1-b3, T1A1-b3, and W2C2. The construction period is from May 25 of this year to July 1, 2027.

[0271] (II) Construction Preparation

[0272] Procedures and site preparation: Complete the procedures for construction permits and water operation registration from May 25 to June 10 of the same year; clear debris from the construction area, level the site (compaction degree ≥90%), build temporary access roads (6m wide, base layer of 300mm thick crushed stone), and divide the work into R5 section 1 and R6 section 2 / 3. Each section is equipped with a processing area (for steel bars and formwork) and a mud treatment area (equipped with 2 mud drying equipment).

[0273] Establishment of the survey control network: Based on the two horizontal control points provided by the owner (X1=3521200.000, Y1=512300.000; X2=3522500.000, Y2=513100.000) and the zero elevation of the revetment, a three-level control network was established using a total station (Leica TS60). The spacing between control points in the first-level network was 500m, the second-level network was 200m, and the third-level network was 50m. The control points were constructed using C30 concrete piers (1m×1m×0.8m), with a forced centering device embedded in the top of the pier. The verification was completed from June 11th to 15th of the same year, and the error was ≤±5mm.

[0274] Equipment and material preparation: Two hydraulic backhoe dredging and piling vessels (Zhonggang Engineering 01588 and Anhang Engineering 218) were deployed, along with three static pressure piling machines (PSG-52 type), three ZX690lCH-5A vibratory hammers, and eight GPS-10 drilling rigs (two for section R5 and six for section R6). Steel sheet piles (PU600×218.5×15.4), cast-in-place pile reinforcement (HRB400E), and ecological blocks were inspected upon arrival at the site. The steel sheet piles were sandblasted to Sa2.5 grade, and the thickness of the anti-corrosion coating was tested and found to be qualified.

[0275] (III) Implementation of Pile Foundation Construction

[0276] Water-based pile driving section (apartment section, R5: 0+829.89~1+103.23)

[0277] Dredging and Positioning: From July 10 to 15 of that year, the Zhonggang Engineering 01588 dredger was used to dredge the rock dumping area (dredging depth to the design mud surface -4.40m). RTK + inertial measurement positioning was used, and the ship position was checked every 10m. If the error exceeded ±10mm, adjustments were made.

[0278] Pile driving construction: A combination of "dredging vessel + static pressure pile driver" was used to drive PU600×218.5×15.4×21m U-shaped steel sheet piles. A 25t truck crane was used to feed the piles. The pile driver's pressing force was controlled between 4500-5200kN (final pressure ≥ 2.3 times the design bearing capacity 874.5kN). During the pile driving process, the verticality was observed in both directions with a theodolite, and the deviation was ≤ 0.5%. 25 piles were constructed per day, and 150 steel sheet piles were completed from July 16 to 25.

[0279] Quality inspection: After pile driving, the integrity of the pile body was tested using the low-strain dynamic testing method. 20% (30 piles) were randomly inspected, and all of them were Class I piles. The pile top elevation deviation was ±30mm, which met the requirements.

[0280] Onshore pile driving section (R5: 0+000~0+246 rock dumping area)

[0281] Obstacle removal and limit frame installation: From July 26th to 30th of that year, excavators were used to remove the boulders (to a depth of -2.82m). Limit frames (300×500 steel, with 0.4×0.4m pile holes reserved) were laid out according to the pile positions. The fixing rod of the limit frame (φ108 seamless steel pipe) was inserted into the soil to a depth of 1.2m. The deviation between the center of the pile hole and the design coordinates was checked to be ≤±5mm.

[0282] Precast square pile driving: ZX690lCH-5A vibratory hammer was used to drive 400×400×15m@1.2m concrete square piles. The vibration frequency was 20-30Hz, and the driving speed was controlled at 1-2m / min. The verticality was re-measured every 5m. If the deviation exceeded 0.5%, the machine was stopped for adjustment. From August 1 to 10, the construction of 80 square piles was completed. The pile top elevation deviation was ±40mm, which met the design requirements.

[0283] Construction of bored piles (R6 Section 2, V1A1-b2 type revetment)

[0284] Casing installation and mud preparation: From August 11 to 15 of the same year, 2m long steel casings (diameter φ700mm) were installed, with a casing center deviation of ≤±50mm and an inclination of ≤1%; the mud was prepared using high plastic clay with a density of 1.2g / cm³, a viscosity of 20s, and a sand content of 3%.

[0285] Hole formation and cleaning: GPS-10 drilling rig with positive circulation drilling, drilling speed: 1.5m / h for silty clay, 1m / h for silty mud, final hole depth 24m (design pile bottom elevation -21.10m), hole cleaning adopts mud circulation method, sediment thickness ≤50mm, mud density reduced to 1.15g / cm³.

[0286] Reinforcing cage installation and concrete pouring: The reinforcing cage was fabricated in two sections (12m each), and welded together (single-sided welding, 10d in length). The spacing of the protective layer spacers was 2m. From August 16 to 25 of the same year, the construction of 50 cast-in-place piles was completed. The underwater concrete (C30) pouring guide pipe was buried at a depth of 2-5m, and the pile top was over-poured by 1.2m. The 28-day strength reached 35MPa, which met the design requirements.

[0287] (iv) Construction of cofferdams and temporary flood control walls

[0288] Non-flood season cofferdam (R6 Section 3, T1B2-d type revetment, September 1-10 of that year)

[0289] Segmented pile driving: A self-propelled barge equipped with a ZX480H-3 vibratory manipulator is used to drive double rows of PU600×218.5×15.4×12m steel sheet piles with a pile spacing of 1.5m. The inner side of the cofferdam is 5m away from the front line of the revetment. A transverse steel waler (20a channel steel) is installed every 30m, and the tie rods (φ20mm steel bars) are spaced 3m apart.

[0290] Seepage prevention and backfilling: A 1.5mm thick HDPE geomembrane and a 200g / m² filter geotextile are laid on the inner side of the cofferdam, with a 100mm overlap width and hot-melt welding; silty clay is backfilled inside the cofferdam in layers (500mm thick), and compacted with a road roller (93% compaction degree). The backfilling was completed to an elevation of 2.80m from September 11th to 15th.

[0291] Drainage system: Three collection wells (elevation -0.5m) are set up inside the weir, equipped with three 4-inch submersible pumps (one of which is a spare). Initial drainage is controlled according to the daily rainfall of 40cm. From September 16 to 20, the water level will be lowered to the mud surface (elevation -1.90m). During this period, the cofferdam is inspected daily, and there is no leakage or displacement.

[0292] Temporary flood control wall (for backup during the flood season, R5 Section 1, September 21-25 of that year)

[0293] Structural construction: Temporary flood control wall 2 is adopted, with bagged soil (silty clay) stacked in an alternating manner, each layer is 300mm thick, with a staggered joint width of 150mm, and the top is made of C20 plain concrete with a 400mm high pressure cap, with a slope of 1:1, a wall length of 200m, and an elevation of 6.10m (5.44m above the 100-year return period high water level).

[0294] Warning facilities: A 1.2m high-speed rail railing is installed on the water-facing side of the flood control wall, an LED warning light (lit at night) is installed every 20m, a red flag is installed every 30m, and "Construction area, do not approach" warning signs are installed at both ends. Yellow and black reflective film is affixed to the top 2m of the warning posts.

[0295] (v) Construction of revetment structure

[0296] V1C1 type revetment renovation (R5: 0+500~0+600, October 1-10 of the same year)

[0297] Old retaining wall removal: Use a hydraulic breaker to remove the top 0.2m of the old retaining wall (retaining the base plate). After removal, clean the surface debris, rinse with a high-pressure water gun, and check the flatness of the base plate. The deviation should be ≤±5mm.

[0298] Wall extension and handrail installation: Tie the reinforcing steel bars for the extension section (HRB400E, φ16@200), install the standard steel formwork, pour C30 concrete (slump 180±20mm), vibrate to compact, and cure for 14 days (cover with geotextile and sprinkle with water); install the flood control wall handrail (stainless steel material, height 1.2m) from October 11th to 15th, and weld the handrail firmly to the wall embedded parts with a deviation ≤±3mm.

[0299] Construction of E1A1-b3 type ecological revetment (R6 Section 2, 0+100~0+200, October 16-30 of the same year)

[0300] Construction of the first-level retaining wall: chisel away the old retaining wall down to the bottom slab (elevation 2.70m), install rebar (φ12@300, depth 180mm), pour C30 concrete foundation, install ecological blocks (size 300×200×150mm), fill the gaps with 1:2 cement mortar, and the top surface of the blocks is at an elevation of 4.60m (4.80m above the highest navigable water level).

[0301] Dual-layer grass slope repair: The slope behind the wall is repaired at a 1:1.5 ratio, a 200g / m² soil and water conservation blanket is laid, and a 300mm thick layer of topsoil (organic matter content ≥3%) is covered. Bermuda grass is planted, and watering and maintenance are carried out on October 31. The survival rate of the grass is ≥90%.

[0302] P2A1-b1 type landscape revetment construction (R6 Section 3, 0+300~0+400, November 1-15 of the same year)

[0303] Patrol Trail and Ecological Empty Boxes: A 2.66m wide patrol trail (C20 concrete, 150mm thick, 1.5% slope) is poured behind the primary retaining wall, with 50mm thick curb stones on both sides of the trail; ecological empty boxes (1000×500×500mm in size) are installed between the trail and the secondary retaining wall, filled with planting soil and planted with irises.

[0304] Secondary retaining wall and drainage ditch: The secondary retaining wall adopts a type A small retaining wall (C30 concrete, 1.2m high), and a 5m wide flood control road is set behind the wall (300mm thick crushed stone base layer, 100mm thick AC-13 asphalt concrete surface layer); a type A drainage ditch (300×400mm, C20 concrete) with a slope of 1.5% is set on the side of the road. The water test was completed from November 16th to 20th, and the drainage was smooth with no water accumulation.

[0305] (vi) Implementation of coordinate linkage and error correction

[0306] Dynamic monitoring and correction: During pile foundation construction and retaining wall pouring, every 10 piles or 20m of retaining wall are constructed, adjacent control points (such as control points C1 and C2 in section R5) are re-measured using a total station. When the re-measurement was conducted on August 5th of the same year, the X coordinate deviation of point C1 was +8mm. The least squares method was used for correction, and the coordinates of subsequent pile position layout were adjusted to X=3521200.008 and Y=512300.000 to ensure that the deviation is ≤±10mm.

[0307] Compensation for errors in water construction: During the pile driving of the apartment section, due to the influence of tides (water level change ±0.5m), RTK dynamic positioning is used to compensate for the hull sway error in real time. For example, when the pile was driven on July 20 of that year, the hull shifted laterally by +12mm. The system automatically adjusted the position of the pile driver, and the final pile position deviation was +9mm, which met the requirements.

[0308] Segment connection accuracy control: At the connection point of R5 and R6 (Baimiao Port), the retaining wall axis was re-measured on May 30, 2026 (end of the first stage). The X-coordinate deviation was +12mm and the elevation deviation was -5mm. By adjusting the position of the retaining wall pouring template in the second stage, the deviation was corrected to +3mm to ensure a smooth connection between the two structural sections.

[0309] (vii) Completion Acceptance

[0310] From June 1st to 15th, 2027, the participating construction units conducted a final acceptance inspection. The inspection included: the dimensions of the revetment structure (axis deviation ±8mm, elevation deviation ±4mm), the integrity of the pile foundation (20% random inspection, Class I piles accounted for 100%), flood control performance (simulated high water level of once in 100 years, no leakage), and ecological landscape (turf survival rate 92%, ecological blocks intact). All indicators met the design and specification requirements. The final acceptance and filing were completed on June 30th, and the project was officially put into use.

[0311] The beneficial effects of the present invention are as follows, compared with the prior art:

[0312] Improved structural adaptability: Through specialized processes of 22 types of bank protection structures in 5 categories, it adapts to the geological (such as silty soil layers and riprap areas) and functional requirements of different bank sections in the middle and upper reaches of rivers. The vertical structure meets the high flood control standard (100-year high water level of 5.44m), the ecological structure enhances the ecological landscape of the river, and the landscape structure takes into account the needs of inspection and navigation.

[0313] Improved construction accuracy: The multi-dimensional coordinate linkage system controls the pile position deviation within ±15mm, the retaining wall axis deviation ≤±10mm, and the elevation deviation ≤±5mm. This solves the problems of coordinate confusion and error accumulation in traditional construction, ensuring that the structure of each section (R5, R6) is closely connected and improving the overall flood control performance.

[0314] Enhanced flood control safety: The phased construction of cofferdams and temporary flood walls allows for seamless integration of construction during the flood season and non-flood season. The cofferdams achieve a seepage prevention rate of over 98%, and the temporary flood walls meet the protection requirements for the highest navigable water level of 4.80m, avoiding the risk of river backflow during construction.

[0315] Construction efficiency and environmental friendliness are optimized: the pile foundation construction equipment is adapted to different scenarios, with a pile driving efficiency of 25 piles / shift on water and 30 piles / shift on land, which is 30% higher than the traditional process; the mud is dried (the dried soil is backfilled after meeting the standards, and the tailwater is reused), and the anti-corrosion treatment of steel sheet piles reduces river pollution and meets the environmental protection requirements of Shanghai.

[0316] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention without departing from the spirit and scope of the present invention. Any modifications or equivalent substitutions should be covered within the scope of protection of the claims of the present invention.

Claims

1. A method for constructing revetments to enhance the flood control capacity of levees in the middle and upper reaches of rivers, characterized in that, include: Step 1: Classify and adapt the revetment structures used for flood control in the middle and upper reaches of rivers to the appropriate construction techniques; Step 2: Construct a multi-dimensional coordinate linkage system for the revetment structure used for flood control in the middle and upper reaches of rivers; Step 3: Implement optimized pile foundation construction technology for revetment structures used for flood control in the middle and upper reaches of rivers; Step 4: Implement cofferdam and temporary flood control wall construction techniques for the revetment structures used for flood control in the middle and upper reaches of rivers; Step 5: Implement the construction process for the revetment structure used for flood control in the middle and upper reaches of rivers.

2. The method for constructing revetments to enhance the flood control capacity of levees in the middle and upper reaches of rivers according to claim 1, characterized in that, Step 1 specifically includes: Based on the geological conditions or functional requirements of the R5 and R6 sections in the middle and upper reaches of rivers, the revetment structures used for flood control in the middle and upper reaches of rivers are divided into five major categories: V-type, P-type, E-type, T-type, or W-type revetment structures, and specific construction techniques are formulated for each type of revetment structure. In step 1, the method for developing specific construction techniques for each type of revetment structure is as follows: V-shaped revetment structure: Its construction process is to construct a vertical flood control wall, which is divided into two categories: renovation and new construction. For renovation, 0.2m of the old retaining wall needs to be removed first, and the height needs to be extended by 0.9m to the design top elevation (0.20m of the revetment zero point), and the flood control wall handrail needs to be installed. For new construction, PU600×218.5×15.4×15m U-shaped steel sheet piles are driven in the front row, and φ600mm@1.8m, 15m long cast-in-place piles are driven in the rear row. After the old retaining wall is removed, the new wall is poured using a molding template. P-type revetment: Its construction process is to construct a landscape-type flood control wall. It consists of a primary retaining wall, a secondary retaining wall, and a hardened structure. A patrol walkway is provided. The front row is constructed with PU600×218.5×15.4×21m U-shaped steel sheet piles, and the rear row is constructed with φ600mm@1.8m cast-in-place piles with a pile length of 18m. An ecological hollow box is set behind the primary retaining wall, and a 5m wide road and A-type drainage ditch are set behind the secondary retaining wall. Type E revetment: Its construction process is to construct an ecological compound grass slope. The first retaining wall is made of ecological blocks, and behind the wall is a compound grass slope. The front row is equipped with PU600×218.5×15.4×18m U-shaped steel sheet piles, and the rear row is equipped with 400×400×18m@1.2m concrete square piles. The grass slope is covered with soil and water conservation blankets and 300mm thick topsoil. T-shaped revetment: Its construction process is to construct a flower bed-shaped double flood control wall. Its flood control road is lower than the secondary wall. Behind the bank is woodland. The front row is driven with PU600×218.5×15.4×21m U-shaped steel sheet piles, and the rear row is driven with φ600mm@1.8m, 21m long cast-in-place piles. The secondary retaining wall adopts a shaped template, and a B-type drainage ditch is set behind the wall. W-type revetment: Its construction process is to construct a wetland-type flood control wall. In front of the wall is a beach. PU600×218.5×15.4×12m U-shaped steel sheet piles are driven at the beach protection line. After the old retaining wall is removed and raised, a 5m wide road and grass ditch are set behind the wall. In step 1, the method for dividing the R5 and R6 segments in the middle and upper reaches of the river is to use the center line of the river channel in the middle and upper reaches as the boundary between the R5 and R6 segments.

3. The method for constructing revetments to enhance flood control capacity of levees in the middle and upper reaches of rivers according to claim 2, characterized in that, Step 2 specifically includes: Step 2-1: Establish a baseline control network; Step 2-2: Perform coordinate linkage calculation; Steps 2-3: Perform dynamic error correction.

4. The method for constructing revetments to enhance the flood control capacity of levees in the middle and upper reaches of rivers according to claim 3, characterized in that, Step 2-1 specifically includes: Based on the plane control points and zero elevation of the revetment structure for flood control in the middle and upper reaches of the river provided by the owner, a three-level control network consisting of a primary network, a secondary network, and a tertiary network is set up using a total station: the primary network covers the entire R5 and R6 segments, the secondary network is divided according to the construction sections of the R5 and R6 segments, and the tertiary network is for local control of individual structures. Each control point of the local control is protected by a concrete pier, and a forced centering device is embedded in the top of the concrete pier. Step 2-2 includes: A plane coordinate-elevation-pile location linkage model was established. The plane coordinates adopted the Gauss projection 3° zone, and the elevation was uniformly adopted from the revetment zero point. Before construction, each control point was checked by GPS-RTK. If the error exceeded ±5mm, it was recalibrated. When laying out the pile locations, the polar coordinate method was used in combination with total station resection. The X coordinate, Y coordinate and elevation of the pile locations were recorded and compared with the design values. If the deviation exceeded ±10mm, adjustments were made.

5. The method for constructing revetments to enhance flood control capacity of levees in the middle and upper reaches of rivers according to claim 4, characterized in that, Step 2-2 specifically includes: The Trimble R10 GPS receiver is used, equipped with a dedicated base station and rover station, and the equipment calibration is completed in advance. Select a known high-level control point as the base station, set up a tripod, and accurately center and level it; Next, configure the parameters of the Trimble R10 GPS receiver: Coordinate system: Gaussian projection 3° zone; Elevation system: bank protection zero point; Sampling interval: 1 second; Observation time: 5 minutes of static observation at each point; Then, the Trimble R10 GPS receiver was used to measure the control points of each secondary network and the control points of the tertiary network point by point. 20 sets of data were collected for each point, and the average value of each set of data was calculated as the measured coordinates. When the absolute value of the difference between the measured coordinates and the design coordinates (ΔX, ΔY, or ΔH) exceeds ±5mm, first check whether the base station is stable, the satellite signal, and the surrounding environment. After eliminating external interference, the control point is measured three times independently. If all three results are out of tolerance, the control point displacement or the initial data is incorrect. If a single control point is out of tolerance, the coordinates of that point are recalculated using the triangulation adjustment method with three surrounding qualified control points. If two or more consecutive control points exceed the tolerance, the control network for the area should be re-established, and the least squares method should be used for overall adjustment. The closure error should be ≤ ±2 when measuring from the starting point to the ending point and back to the starting point. mm; The corrected control points must be reviewed and signed by the supervision unit before they can be used for subsequent construction. Then a Leica TS60 total station was used, equipped with a 2m prism pole; Select 2-3 control points that have been verified and approved near the pile locations to be laid out; Input the coordinates of the control points, and the total station will automatically calculate the station coordinates and check the intersection accuracy. If the accuracy is not met, increase the number of control points and re-intercept; Input the X coordinates, Y coordinates, and elevation of the designed pile location; The total station calculates the layout angle and distance, and directs the prism to move to the theoretical position; Repeatedly adjust the prism position until the difference between the measured coordinates and the design coordinates is ≤ ±5mm; Measure the elevation of the pile location using a total station and compare it with the design elevation; The measured X-coordinate, Y-coordinate, and elevation are recorded electronically, and the deviations ΔX, ΔY, and ΔH obtained by subtracting them from the design values ​​are automatically calculated. When any value of |ΔX|, |ΔY|, or |ΔH| exceeds ±10mm, stop the layout and analyze the reason: If the error is due to measurement error, rebuild the station and set out again; If it is a systematic error, trace back to the control point verification process and recalibrate. Planar position adjustment: Obtain the same adjustment amount based on ΔX and ΔY, mark the new position on the ground with a small steel ruler, and measure and verify again until the deviation is ≤ ±10mm; Elevation adjustment: If it is a pile foundation, adjust the height of the casing or the drilling depth; if it is a precast pile, adjust the driving depth of the pile. Overall deviation of pile group: When the deviation of three or more consecutive piles exceeds the limit, the control network should be re-inspected and the local control network should be re-laid if necessary. Considering the effects of water flow and tides, a dynamic stakeout method was adopted, with measurements repeated every 5 minutes, and the average value was taken as the final location. Pile locations adjacent to existing structures: When adjustments may affect existing structures, a special adjustment plan shall be prepared and submitted to the design unit for approval. After the adjusted pile positions are deemed acceptable, they must be inspected and accepted by the supervising engineer, and the "Pile Position Layout Acceptance Record Form" must be signed before pile foundation construction can proceed.

6. The method for constructing revetments to enhance the flood control capacity of levees in the middle and upper reaches of rivers according to claim 5, characterized in that, Steps 2-3 include: In the key processes of pile driving and retaining wall pouring for the revetment structure, after every 10 piles or 20m of retaining wall are constructed, the adjacent control points are re-measured, and the cumulative error is corrected using the least squares method. For the construction section on the water, considering the influence of water flow and tide on the measurement, a dynamic positioning method is adopted to compensate for the error caused by the swaying of the ship in real time, ensuring that the pile position deviation is ≤±15mm.

7. The method for constructing revetments to enhance the flood control capacity of levees in the middle and upper reaches of rivers according to claim 6, characterized in that, Steps 2-3 specifically include: After every 10 piles are completed, the adjacent 2-3 tertiary control points of the construction section are immediately re-measured; retaining wall pouring process: after every 20m of retaining wall is poured, 3 secondary or tertiary control points corresponding to the two ends and the middle of the retaining wall are selected as re-measurement objects to ensure coverage of the current construction area; It uses a Leica TS60 total station, equipped with a 2m centering rod and temperature and pressure sensors; Set up a Leica TS60 total station at the starting control point of the re-measurement. After centering and leveling, let it stand for 10 minutes to allow the Leica TS60 total station to stabilize its temperature. Input the design coordinates of the control point, set the measurement mode to "corner-side measurement", and simultaneously collect temperature data. air pressure The data is used for distance measurement correction; Three rounds of observations were conducted on the target control point. Each round included measurements of the horizontal angle, vertical angle, and slope distance. The horizontal angle observation adopted the full-circle direction method, with a half-measurement regression zero error ≤6″ and an inter-round difference ≤9″. The slope distance observation required meteorological correction, with a distance difference of ≤2mm per round. Electronic handbooks were used to record data, and the measured coordinates of control points for each round of measurement were automatically calculated. The average value of the three rounds of data was taken as the final measured value. The observation time, meteorological conditions and instrument status were also marked. Calculate the difference between the measured coordinates and the design coordinates of the re-measured control points. ( , , If the absolute value of any difference exceeds ±5mm, it is determined that there is a cumulative error and the correction process needs to be initiated. After initiating the correction process, take all the re-measured control points (set as n, n≥3) within the current construction section as the observation objects and establish the error equation: V=AX−L, where: V is the observation value correction vector; A is the coefficient matrix; X is the control point coordinate correction vector to be determined; L is the difference vector between the observation value and the design value; Based on the principle of least squares, solve for the coordinate correction vector: X = , where P is the weight matrix, which is assigned a value according to the observation accuracy; Implementation and Verification: Calculate the coordinate corrections for each control point and correct the original design coordinates accordingly. ， , ； After correction, re-measure the control points to verify whether the corrected coordinate deviation is ≤ ±5mm; if it is still out of tolerance, check the rationality of the error equation construction and recalculate until the accuracy requirements are met. The corrected control point coordinates were entered into the construction surveying system for the construction of the revetment structure for flood control of the middle and upper reaches of the river, serving as the benchmark for the subsequent construction of 10 piles / 20m retaining walls. Next, a Trimble R10 GNSS receiver was used, paired with an IMU inertial measurement unit; the base station was set up at a stable control point on shore, and the rover station was installed on top of the bridge of the piling vessel to ensure that the antenna height was fixed. Equipped with a shipborne data processing terminal, it receives GNSS and IMU data in real time, with a sampling interval of 1Hz to ensure data transmission delay ≤0.5 seconds; In calm waters where the revetment structure is located, the piling vessel is fixed in place. Three known coordinate points on the hull deck are measured using a total station and compared with the hull attitude output by the GNSS+IMU. The initial attitude deviation of the IMU is corrected to ensure that the attitude measurement error is ≤ ±0.05°. Transformation parameters from the WGS84 geodetic coordinate system to the engineering plane coordinate system were established. The 7-parameter transformation method was adopted, and the transformation parameters were calculated using GNSS observation data from 3 known plane control points on the shore. The transformation residual was ≤ ±3mm. Real-time water flow velocity and tidal level changes in the middle and upper reaches of the river during the construction period were obtained from hydrological stations along the river to establish the effect of water flow on the lateral displacement of the ship. Impact Model: , Changes in ship elevation caused by tides are directly compensated for in real time using water level data. ; The IMU acquires the ship's roll angle α and pitch angle β in real time to calculate the positional deviation of the pile location layout points. , Meanwhile, the hull sway amplitude is determined by the standard deviation σ of GNSS data. When σ > 5mm, the dynamic compensation algorithm is activated. After activating the dynamic compensation algorithm, the shipborne terminal fuses GNSS position coordinate data and IMU attitude data in real time, and uses a Kalman filter algorithm to remove outlier data, thereby outputting the filtered real-time position coordinate data of the ship. ; Based on the established error model, calculate each error component ( , , , , The filtered position data coordinates are then corrected. ； The compensated pile coordinates ( ) and design coordinates ( Real-time comparison is performed to calculate the deviation value. , , The driver issues adjustment instructions to the operator via the display screen in the cab, and the pile driving operation can only begin when the deviation value is ≤ ±15mm.

8. The method for constructing revetments to enhance the flood control capacity of levees in the middle and upper reaches of rivers according to claim 7, characterized in that, Step 3 specifically includes: Equipment selection and adaptation: The equipment is selected according to the construction scenario. The water pile driving section adopts a hydraulic backhoe dredging and pile driving vessel, combined with a static pressure pile driver. After dredging, the piles are driven, with an efficiency of 25 piles / shift. The land pile driving section adopts a combination of ZX690lCH-5A vibratory hammer and static pressure pile driver. In narrow sites, a 25t truck crane is used to feed the piles. Pile foundation quality control: Steel sheet piles need to be sandblasted to remove rust before entering the site, and anti-corrosion treatment should be carried out 5m below the pile top; Drilled cast-in-place piles are constructed using GPS-10 drilling rigs with positive circulation, mud density is controlled at 1.1-1.3g / cm³, sand content ≤4%, sediment thickness after cleaning ≤50mm, reinforcement cage protective layer deviation ±20mm, underwater concrete pouring guide pipe burial depth 2-5m, and over-pouring at the pile top ≥1m; Construction of imitation wood piles and precast square piles: The number of layers of imitation wood piles shall be ≤8, and the exterior shall be painted before installation; the precast square piles shall be positioned by a limiting frame, and the verticality shall be observed in both directions by a theodolite during pile driving, with a deviation of ≤0.5%, and the pile hole shall be backfilled with ballast in a timely manner after the pile is driven.

9. The method for constructing revetments to enhance the flood control capacity of levees in the middle and upper reaches of rivers according to claim 8, characterized in that, Step 4 specifically includes: The cofferdam design is phased: the cofferdam structure remains the same during the flood season and the non-flood season, with only the pile length adjusted. During the flood season, the double-row steel sheet piles are 15m long, while during the non-flood season, they are 12m long; the single-row combined piles are 18m long during the flood season and 15m long during the non-flood season. The cofferdam is constructed in sections, with self-propelled barges equipped with ZX480H-3 vibratory manipulators for pile driving on the water, and a pile driving vessel is provided for material turnover. Seepage prevention and drainage optimization: a seepage-proof geomembrane and a filter geotextile are laid on the inner side of the cofferdam. The backfill soil inside the cofferdam is silty clay with a low permeability coefficient and is backfilled in layers. The initial drainage is controlled according to the daily precipitation ≤50cm. A water collection well is set up and equipped with 3 4-inch submersible pumps. Light wellpoint dewatering is used during the bank protection construction period. Drainage ditches and water collection wells are set up around the foundation pit to ensure dry construction. Temporary flood control wall connection: Temporary flood control wall two is used during the flood season, and temporary flood control wall three is used during the non-flood season; before the old retaining wall is demolished, the temporary flood control wall is constructed first, and the connection with the main structure is reinforced with steel bars to ensure flood control closure. During demolition, the process is as follows: water release → removal of tie rods → excavation → pile extraction → dredging. The excavated soil is transported to the next section or spoil disposal site by dredger.

10. The method for constructing revetments to enhance the flood control capacity of levees in the middle and upper reaches of rivers according to claim 9, characterized in that, Step 5 specifically includes: Overall process: Construction preparation → pile foundation construction → construction according to the appropriate revetment structure construction technology → road construction → drainage construction → flood control house construction → landscaping → ancillary facilities → final acceptance. Key process control: old retaining walls are demolished using hydraulic breakers, and the rebar depth is ≥15d when the base plate is retained. New retaining walls are poured using standardized steel formwork, vibrated to ensure compaction, and cured for ≥14d. Before installing ecological blocks, the foundation must be leveled, and gaps must be filled with cement mortar. The compound grass slope is trimmed at a slope of 1:1.5, and the compaction degree of the planting soil is ≥85%.

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