Construction method of dam composite flexible diaphragm wall

Abstract

The invention relates to the field of water conservancy project dams, in particular to a construction method of a dam composite flexible diaphragm wall. 2, equipment is in place; thirdly, wall forming is conducted through a construction method, and the equal-thickness cement soil underground continuous wall is formed; fourthly, the anti-seepage core plate is inserted; the anti-seepage core plate is composed of a body, a plurality of bundles of optical fibers are distributed inside or on the outer surface of the anti-seepage core plate, and the optical fibers extend downwards in the length direction of the body and can monitor environmental changes of the body and the underground diaphragm wall around the body. A continuous and uniform dam composite flexible anti-seepage wall can be formed for a winding dike, the erosion resistance and disturbance resistance of the anti-seepage wall can be improved, the anti-seepage durability is improved, meanwhile, whether a seepage area exists in the continuous wall or not is monitored through the anti-seepage core plate, and early warning is provided for effectively taking precautionary measures in time.

Description

Technical Field

[0001] The invention relates to the field of water conservancy project dams, and in particular to a construction method for a composite flexible anti-seepage wall of a dam. Background Art

[0002] Earthen embankments are the main type of embankments on major rivers and lakes in my country, and strengthening the anti-seepage work of embankments is the key to the long-term stability of embankments. Traditional anti-seepage methods mainly use the embankment's own soil anti-seepage, casing well backfill, cement mixing pile anti-seepage, and some use high-pressure rotary jet piles, geomembrane anti-seepage, concrete formwork anti-seepage and other methods. When extreme weather occurs frequently, such as continuous heavy rainfall and long-term high water levels, the harsh environment has caused serious damage to the embankment, increasing the risk of major dangerous situations such as pipe bursts and dam breaches caused by embankment leakage.

[0003] The existing embankment has problems such as low compaction of its own soil and well backfill soil, and narrow embankment working space, which leads to insufficient durability of cement mixing piles, and problems of offset settlement and overlap failure of geomembranes and concrete panels, and high-pressure jet grouting piles easily damage the embankment structure itself. In addition, the embankment has complex and changeable terrain and a long length. These factors together lead to high construction costs and increased construction difficulty of reinforcement and anti-seepage projects.

[0004] The traditional mixing pile method, namely the SMW method, often faces challenges such as uneven wall thickness and substandard strength under complex geological conditions. The cement soil continuous wall is simple to construct, has uniform wall thickness and low cost. However, due to the problems of heavy construction equipment, large size and strong construction disturbance of the traditional cement continuous wall, it is difficult to apply it to the anti-seepage treatment of general embankments.

[0005] In this regard, the Chinese invention patent publication number is CN113356295A, which discloses "a kind of underground deep narrow groove continuous sawing equipment". Through the cooperation of the translation frame and the translation support frame, it can realize the vertical feeding and horizontal feeding of the underground deep narrow groove forming, and cut the deep narrow groove of the wall structure according to the needs with high efficiency and quality; the Chinese invention patent publication number is CN116122370A, which discloses "a kind of middle wall forming TRD construction equipment". By fixing the working device in the middle of the frame, the construction space of the working vehicle is reduced, and it is suitable for the TRD construction of 6-8m embankments. The TRD construction method is to cut the soil layer by rotating the chain saw, and inject the solidifying liquid to force it to mix and stir with the in-situ soil to form a cement continuous wall. Steel sections can also be inserted into the wall to increase the rigidity and strength of the cement continuous wall.

[0006] Although the construction technology of cement continuous wall has made progress, its insufficient durability and low applicability still exist. Especially in the winding embankment, the continuous wall is difficult to form an effective closed anti-seepage body and it is difficult to meet the service life requirements of high-grade embankments.

[0007] The Chinese invention patent publication number is CN118110182A, which discloses "a method for constructing a retaining pile wall combining a TRD method and sheet piles". The underground cement soil continuous wall is formed by using a TRD pile driver to cut and mix the soil in a channel-like manner, and sheet piles are inserted into the continuous wall. The plastic sheet piles of each sheet pile are connected as a whole through a mortise and tenon structure to form a retaining pile wall. By introducing a combination of plastic sheet piles and steel support piles, a water-stopping effect can be exerted to form an effective water-stopping curtain. In fact, this patent solution is mainly used in the enclosure of foundation pits. The land around the foundation pit can be leveled and compacted, and the enclosure is relatively wide, generally large through TRD slotting, between 100cm and 120cm. After slotting, the steel is inserted below the bottom of the cement continuous wall to form the support piles of the foundation pit, and the steel also forms the support structure of the plastic sheet piles in the cement wall.

[0008] Although the TRD method combined with sheet piles has achieved some results in foundation pit protection, its construction effect and stability in dam anti-seepage projects still need to be further verified due to factors such as the complex and changeable dam terrain and large differences in soil quality. In addition, the economy, construction efficiency and potential impact of this technology on the surrounding environment are all factors that need to be focused on in the application of dam anti-seepage. The application of the retaining pile wall construction method to dam anti-seepage projects has not yet been put into practice and verified, and there are many technical challenges and construction adaptability issues.

[0009] Moreover, as a permanent anti-seepage dam, it is difficult to monitor leakage-induced pipe bursts through effective monitoring methods, and it is difficult to assess or predict the risk of dam failure before a dangerous situation occurs, and to take timely and effective preventive measures. Summary of the invention

[0010] In view of one or more problems existing in the existing dam anti-seepage, the present invention provides a construction method for a composite flexible anti-seepage wall of a dam. By adopting composite materials and advanced construction technology, the dam anti-seepage wall exhibits the flexibility required by the design and can flexibly adapt to various deformations and displacements of the dam, especially on winding embankments. It can form a continuous and uniform composite flexible anti-seepage wall, while significantly improving the anti-erosion and anti-disturbance capabilities of the anti-seepage wall and enhancing the anti-seepage durability. At the same time, the anti-seepage core plate is used to monitor whether there is a leakage area in the continuous wall, ensuring that the risk of dam break is evaluated or predicted before a dangerous situation occurs, and providing early warning for timely and effective preventive measures.

[0011] The purpose of the present invention is achieved through the following technical solutions: The present invention provides a construction method for a composite flexible anti-seepage wall of a dam, comprising: Step 1: Measurement and positioning, marking the coordinates of the corner points of the center line of the cut-off wall on the top of the dam, and using the excavation mechanism to excavate the working trench along the parallel trajectory of the center line of the cut-off wall; Step 2: Equipment is in place, and the construction machine equipment is transported to the top working position of the dam; Step 3: Construction method wall, using a construction machine to cut along the working groove to the designed depth, and forcibly mix and stir the original soil and solidifying liquid to form an underground continuous wall of equal thickness cement soil; Step 4: inserting the anti-seepage core plate. After the construction reaches a working surface larger than the width of the anti-seepage core plate, insert the anti-seepage core plate in the middle of the cement underground continuous wall. The bottom of the anti-seepage core plate is inserted to the designed depth. When multiple anti-seepage core plates are inserted, they are connected with adjacent anti-seepage core plates to form a composite flexible anti-seepage wall of the dam. The anti-seepage core board includes a main body, which includes a plate-shaped main board and wing plates arranged on both sides of the main board. The wing plates are provided with connecting ends, including optical fibers and transceivers connected to the upper ends of the optical fibers. Several bundles of optical fibers are distributed inside and / or on the outer surface of the main body. The optical fibers extend downward along the length direction of the main body and are used to monitor environmental changes of the main body and / or its surrounding underground continuous walls.

[0012] The present invention implants an anti-seepage core plate in the cement soil underground continuous wall. The solidity of the cement wall further enhances the stability of the anti-seepage core plate, and the anti-seepage core plate further enhances the anti-seepage effect of the cement wall, ensuring that it is not easy to deform and fail in long-term use. By collecting the stress changes of the anti-seepage plate or the thermal radiation effect and vibration fluctuation changes in the water around the anti-seepage plate through optical fiber, it is determined whether the environment around the anti-seepage plate has changed, and it is inferred whether there is a leakage point. The risk of dam failure is evaluated or predicted before the danger occurs, and preventive measures are taken in a timely and effective manner.

[0013] Preferably, a plurality of anchor rods extending along the length direction of the main board are arranged on the surface of the main board, the anchor rods include a main rod and a connecting part, the connecting part connects the main rod and the main board, the anchor rods are evenly and staggeredly distributed on both sides of the anti-seepage core plate, and after the anti-seepage core plate is inserted into the underground continuous wall, the anchor rods are anchored and combined with the underground continuous wall.

[0014] In the present invention, the anchor rod can strengthen the structural strength of the main board and enhance the stability of the anti-seepage core board. It can still be used alone without the support of H-shaped steel, wooden piles, etc. The anchor rod is anchored in the underground cement continuous wall to form a good connection with the surrounding land. When the continuous wall is deformed or leaking, the anchor rod acts as the antenna of the optical fiber to amplify the signal of environmental changes for the optical fiber.

[0015] Preferably, the cross-sectional width of the main rod is greater than the cross-sectional width of the connecting portion, or the diameter of the main rod is greater than twice the width of the connecting portion.

[0016] Preferably, an optical fiber is provided between the main rod and the main board near the connection portion. The main rod has a large cross-sectional area and can form an effective anchoring effect to prevent surrounding soil loss, thereby achieving a better anti-seepage effect and ensuring that the anti-seepage core board is more stable under complex geological conditions.

[0017] Preferably, the distance between the top of the anchor rod and the surface of the main board is greater than the thickness of the main board. The provision of the anchor rod can provide the main board with a bending resistance nearly twice the thickness of the main board in the vertical direction, while reducing the overall resistance, so that the anti-seepage core board can be implanted underground. At the same time, the thickness of the main board cannot be too large, so that the anti-seepage core board has a certain flexibility in the horizontal direction and has the ability to deform to adapt to complex geological environments.

[0018] Preferably, the connecting end includes a first connecting end and a second connecting end, the first connecting end includes a first end plate and a convex head, the second connecting end includes a second end plate and a concave head, and an optical fiber is arranged on the first end plate or the second end plate, or on the convex head or the concave head.

[0019] Preferably, in step 3, the thickness of the underground continuous wall is 30 cm to 45 cm; In step 4, the inserted anti-seepage core plate has an overall thickness of 10 cm to 15 cm, and the anti-seepage core plate is disposed as a whole in the middle of the width of the underground continuous wall.

[0020] In the present invention, the cement wall is 2-3 times the thickness of the anti-seepage plate, and the thickness of the cement wall is reasonably designed, which ensures the anti-seepage effect while avoiding unnecessary damage to the existing dam structure during construction.

[0021] Preferably, the width of the working trench is set to 0.5 to 0.7 m, and the depth needs to be more than 1.0 m.

[0022] Preferably, in step three, the cement content is adjusted according to the average bonding strength of the soil layer, the cement content is controlled between 5% and 15%, and the cement soil strength is between 5% and 60% of the original soil layer strength.

[0023] Preferably, the vertical deviation of the anti-seepage core board is less than or equal to 1 / 300, and the first anti-seepage core board is lifted and inserted into the cement soil slurry to keep it in the center until the top of the anti-seepage core board is 0.8m to 1m higher than the slurry; the second anti-seepage core board is lifted and the joints are connected to connect the two anti-seepage core boards until the top of the anti-seepage core board is 0.8m to 1m higher than the slurry; the first anti-seepage core board is re-pressed until it is 0.2m higher than the slurry; when inserting the board, ensure that the cement soil has not initially set. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the structure of the anti-seepage core plate from a top view; Figure 2 It is a schematic diagram of the main structure of the anti-seepage core plate; Figure 3 This is a schematic diagram of the narrow wall structure of the cut-off wall; Figure 4This is a schematic diagram of the wide wall structure of the cut-off wall; Figure 5 This is a cross-sectional structural diagram of the cut-off wall on the dam; Figure 6 This is a top-down structural diagram of the cut-off wall on the embankment; Figure 7 This is the process flow chart of TPD method.

[0025] In the figure: 1-main body, 2-main board, 3-wing board, 4-first connecting end, 41-first end board, 42-convex head, 5-second connecting end, 51-second end board, 52-concave head, 6-anchor rod, 61-main rod, 62-connecting part, 71-optical fiber, 72-transceiver, 10-cement wall, 20-river surface, 30-dam. DETAILED DESCRIPTION

[0026] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments should have elements such as specificity, operability, typicality, clarity, completeness, comparability, appropriateness and flexibility to ensure that the innovation and practicality of the invention are fully demonstrated. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limitations on the present invention.

[0027] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "clockwise", "counterclockwise", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as limiting the present invention.

[0028] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, the term "plurality" refers to a quantity of two or more, and this definition is not subject to other limiting conditions.

[0029] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0030] Embodiment 1:

[0031] The present invention discloses a construction method for a composite flexible anti-seepage wall of a dam, whose English name is Trench Cutting Plastic Pile-mixing Deep Wall Method (TRD method is the full name of Trench Cutting Re-mixing Deep Wall Method, in which a polymer anti-seepage plate is added on the basis of TRD), referred to as TPD method. It is a construction method of an anti-seepage technology of a composite flexible anti-seepage wall of a dam, which is developed on the basis of the traditional TRD method to solve the problem of anti-seepage of existing dams and intersecting buildings.

[0032] The core principle of the TPD method is to use the rotary motion of the chain saw to accurately cut the soil layer until it reaches the designed depth. Then, a cross-cutting operation is performed, and cutting fluid and curing fluid are injected in sequence to fully mix them with the in-situ soil. Finally, a continuous sleeved anti-seepage core plate is inserted to construct a composite flexible anti-seepage wall with uniform thickness, continuity, and excellent anti-seepage performance.

[0033] like Figure 1 - Figure 2 As shown, the anti-seepage core plate includes a body 1, and the body 1 includes a plate-shaped main board 2 and wing plates 3 arranged on both sides of the main board 2. One end of the wing plate 3 is connected to the main board 2 and extends outward, and connecting ends are respectively arranged at the other ends of the two wing plates 3, and the connecting ends are respectively a first connecting end 4 and a second connecting end 5.

[0034] The first connecting end 4 includes a first end plate 41 and a convex head 42, and the second connecting end 5 includes a second end plate 51 and a concave head 52. The convex head 42 and the concave head 52 are engaged with each other to achieve sequential connection and tight fixation of the anti-seepage core plates.

[0035] The main board 2 is provided with an anchor rod 6, which includes a main rod 61 and a connecting portion 62. The main rod 61 is generally cylindrical and extends parallel to the length direction of the main board 2. The connecting portion 62 connects the main rod 61 and the main board 2. The width of the connecting portion 62 is smaller than the diameter of the main rod 61, ensuring that the anchor rod 6 is firmly embedded.

[0036] When the optical fiber 71 is embedded in the body 1, the embedding method is flexible and diverse. It can be arranged along the preset groove inside the main board 2 or the wing plate 3, or it can be directly embedded during the molding process of the main board 2 or the wing plate 3. Doing so can ensure that the optical fiber 71 is tightly combined with the body 1, thereby improving the accuracy and stability of monitoring. The monitoring optical fiber selected by the sensor is a micro-point dense distributed strain sensing optical cable. By burying the optical fiber, that is, co-extruded into the anti-seepage core board, it is a dense strain sensing optical fiber, which can monitor the stress condition of the board.

[0037] The preparation process of the anti-seepage core board is as follows: the extrusion die opens a channel to extrude the plastic steel plate to form a whole with the embedded optical fiber and the sheet pile. After forming, it is sent to the shaping die to dissipate heat and cool down through cold water to cool the plastic steel plate. The outer layer of the optical fiber needs to be wrapped with an insulation layer and a reinforcement layer to protect the internal optical fiber bundle, and then it is pulled and co-extruded to form a whole with the sheet pile. The outer layer of the optical fiber is insulated and reinforced with materials such as aramid fiber, Teflon sleeve, and metal sleeve to improve the strength and thermal insulation performance of the optical fiber bundle.

[0038] The composite flexible anti-seepage wall constructed by TPD method has the advantages of no joints, good water-stopping performance, high vertical accuracy, uniform texture, thin wall, etc. Its permeability coefficient is required to reach k≤1*10^-7cm / s, and the 28d unconfined compressive strength of the wall is ≥0.3MPa. TPD construction has the advantages of high safety, high efficiency, low comprehensive cost, wide applicable geology, and strong site adaptability.

[0039] Compared with the traditional TRD method anti-seepage wall, the composite flexible anti-seepage wall has a thin wall body, good dam stability, good anti-seepage effect, strong anti-erosion ability and strong anti-disturbance ability.

[0040] 1. TPD process.

[0041] like Figure 7 As shown in the figure, the TPD process flow, the main key steps are described below.

[0042] 1. Measurement and positioning.

[0043] 1.1 Measurement and setting out. Before construction, first accurately calculate the coordinates of the corner points of the center line of the anti-seepage wall according to the design drawings and coordinate reference points, use measuring instruments to set out, and check the coordinate data, and at the same time, prepare the protective piles. Notify the relevant units to conduct the setting out and review.

[0044] The center line of the cut-off wall is generally set on the center line of the top of the dam, ensuring that it is parallel to the axis of the dam and the stress is moderate. The measurement work must ensure high precision and the error must be strictly controlled within the range of ±5mm to ensure the accuracy of the position of the cut-off wall.

[0045] 1.2. Dig positioning trench.

[0046] According to the equipment weight requirements of the TPD method, after the precise setting out of the center line of the anti-seepage wall is completed, a series of reinforcement measures such as laying steel plates are immediately implemented on the construction site to ensure that the site can bear the weight of the mechanical equipment and ensure the stability of the pile driver during operation. The excavation mechanism is used to excavate the working trench along the parallel trajectory of the center line of the anti-seepage wall. The width of the trench is set to about 0.6 meters, and the depth needs to exceed 1.0 meters.

[0047] 2. The equipment is in place.

[0048] The main machine is in place. Check the situation in the upper, lower, left and right directions before moving. If any obstacles are found, they should be removed in time. After the move, check the positioning and correct it in time. The main machine should be stable and flat.

[0049] The cutting chain saw is installed in place, and the cutting chain saw is hoisted by a crane and connected to the main machine for installation.

[0050] 3. TPD method to build the wall.

[0051] First, determine the cement content and pre-mix cement slurry based on the geological survey report; during construction, slightly adjust the cement content according to the distribution of different soil layers in each work section.

[0052] The cutting box is sunk, and then cuts vertically to the designed depth. During the cutting process, the configuration is controlled and injected. Cut longitudinally into grooves, and inject cutting agent slurry at the bottom of the cutting box to cut the soil layer for a certain distance, then withdraw the excavation to the original location, cut back and inject solidifying slurry, stir the composite soil, and start solidifying liquid to force it to mix and stir with the original soil to form an underground continuous wall of equal thickness cement soil.

[0053] The cutting tool moves forward and reciprocates to carry out the construction of the next section of underground cement continuous wall.

[0054] The distribution of different soil layers is different. The average cohesion of the soil layer is calculated after stirring and mixing. The cement content is adjusted according to the average cohesion of the soil layer. The cement content is controlled between 5% and 15%. The strength of cement soil should not be higher than 60% of the strength of the original soil layer. Generally, the strength of cement soil is between 5% and 60% of the strength of the original soil layer. The greater the difference in medium strength, the lower the anti-disturbance ability.

[0055] Adjust the aeration volume according to the cutting forward speed: increase the forward speed and increase the aeration volume to make the mixing amount of cement soil slurry the same at each moment.

[0056] The thickness of the cement soil underground continuous wall is 30-45cm, which can adapt to the minimum width of 3-4m. The excavation depth can reach 15-20m.

[0057] 4. Insert the anti-seepage core board.

[0058] After the construction reaches a certain working surface, the high-strength anti-seepage core plate is inserted. The insert plate needs to extend the working surface by 2 meters. The anti-seepage core plate must be kept vertical and inserted vertically into the cement soil mixing pile. The verticality deviation of the inserted anti-seepage core plate is less than or equal to 1 / 300, and the insertion time must be controlled within 3 hours after the completion of the mixing wall construction.

[0059] Lift the first anti-reverse seepage core board, insert it into the cement soil slurry and keep it in the middle position until it is 1 meter above the slurry; lift the second anti-seepage core board, sleeve the joints, connect the two anti-seepage core boards to each other, and insert them into the slurry until they are 0.8 to 1 meter above the slurry; then re-press the first anti-seepage core board until it is 0.2m above the slurry, insert the first anti-seepage core board into the slurry, and construct the next anti-seepage core board in turn. The first anti-seepage core board is pressed to a position of 0.8-1m to facilitate the sleeve connection of the second anti-seepage core board. If it is too low, it will be difficult to sleeve it. Therefore, when the second anti-seepage core board is pressed to 0.8-1m, the first anti-seepage core board needs to be pressed down again until it is 0.2m above the slurry. Repeat this process to construct the third, fourth, and other anti-seepage core boards.

[0060] When inserting the boards, it is necessary to ensure that the cement soil has not yet initially set, and the board insertion operation should be completed within 2 hours before the initial setting to avoid the vibration during the board insertion process affecting the solidification of the cement soil around the completed boards.

[0061] When the anti-seepage core plate is inserted into the continuous wall, the continuous wall is not completely hardened, the insertion is relatively smooth, and there is no complex geographical environment. The anti-seepage core plate is smoothly inserted into the bottom of the continuous wall without the need for additional piling support. Its strength alone can fit closely with the continuous wall to form a continuous flexible wall overall structure.

[0062] 5. Pull out the cutting box.

[0063] After the construction is completed, the cutting box is pulled out in sections using the TPD host.

[0064] A construction method for a composite flexible anti-seepage wall of a dam. The dam slot width is small, which is suitable for narrow dam bodies and is easy to construct. The anti-seepage core plate has a watertight property, which significantly enhances the anti-seepage capacity of the area. The existing construction method is vibration pile sinking, which has a large disturbance to the local area and many soil layers cannot be driven into. Due to the particularity of the dam, the water jet method cannot be used for construction, which has many restrictions.

[0065] like Figure 3 - Figure 4As shown, the wall thickness of the anti-seepage core board, the main body 1 is 9mm, the overall width is 650mm, the length is 15m (adjustable according to engineering requirements), and the main board 2 is 402mm long. The width of the wing plate 3 projected to the cross section perpendicular to the main board 2 is 120mm, and the length projected to the surface of the main board 2 is 34mm. The wing plate 3 forms an angle A with the main board 2, tanA=120 / 34. The width of the connecting end is 90mm and is parallel to the main board 2. The distance from the cross-sectional end of the anchor rod 6 to the side of the main board 2 is 11mm, the diameter of the main rod 61 is 9mm, and the width of the connecting end 62 is 4mm. The anchor rod 6 ensures that it can penetrate into the soil layer to form a firm support. The spacing of the anchor rods 6 is designed to be 80mm to 90mm, which can be slightly adjusted to ensure that the soil is evenly stressed and tightly connected to the cement underground continuous wall.

[0066] Embodiment 2:

[0067] In this embodiment, optical fibers are arranged inside and on the surface of the anti-seepage core plate in Embodiment 1.

[0068] Sensors are arranged inside or on one side or both sides of the body 1 of the anti-seepage core board, and the sensors are used to monitor the anti-seepage status in real time, and the data is transmitted to the central processing system to analyze the leakage risk.

[0069] The anchor rods 6 are evenly distributed on the surface of the main board 2, and their spacing is kept consistent, so as to ensure that the force of the entire structure reaches a balanced state. The anchor rods 6 are arranged on the surfaces of both sides of the main board 2 at the same time, and the anchor rods 6 on both sides are staggered to form a cross-support structure to enhance the overall tensile strength. The connection between the anchor rods 6 and the main board 2 is connected by one-piece extrusion molding and other one-piece molding technologies. Through this design, not only the overall stability of the structure is improved, but also the service life of the anti-seepage system is extended. The precise monitoring and data analysis of the sensor enable the system to timely warn of potential leakage risks and ensure long-term safe operation. In addition, the wing plate 3 of the main body 1 is made of high-strength composite material to enhance the deformation resistance, while requiring a certain deformation flexibility, so that the wing plate 3 can bend moderately when subjected to external force.

[0070] The sensor is a linear monitoring optical fiber 71. The optical fiber 71 is arranged on the surface of the main board 2 or / and the wing board 3 through a preset path to ensure full coverage of the monitoring area.

[0071] The optical fiber 71 can be set both inside and on the surface of the anti-seepage core board. The optical fiber 71 of the sensor is fixed on the surface of the main board 2, and the optical fiber can be selected as an active heating type stable vibration composite sensing optical cable. The optical fiber is an active heating type stable vibration composite sensing optical cable, and the main installation method is to stick it on the anti-seepage core board, which requires the process monitoring of heat radiation and vibration from one side to the other. Of course, it can also be pre-buried in the board. The optical fiber 71 is fixed between the anchor rod 6 and the main board 2. Specifically, the sensor is placed near the connection part 62 between the main rod 61 and the main board 2. Therefore, the sensor can be fixed on the main board 2 or the connection part 62, or fixed between the main rod 61 and the connection part 62, to ensure that the sensor is protected while being able to monitor the connection status of the main board 2 and the anchor rod 6 with the surrounding environment, and to feedback data in real time to improve the stability and reliability of the anti-seepage system.

[0072] The anti-seepage core board is used to install the surface monitoring optical fiber, and the optical fiber is configured on the entire board surface by anchor rod secondary bonding and other methods. The carbon fiber cloth is soaked in ethyl cyanoacrylate, and the optical fiber cable is covered and fixed on the convex part of the anchor rod on the anti-seepage core board surface. Other polymer materials can also be used to wrap the optical fiber 71, and a steel wire outer layer is added on the outer layer.

[0073] When the anti-seepage core board is in the formation, the optical cable is powered on the upper equipment, the optical cable generates heat and vibrates, and the heat radiation effect and vibration fluctuation of heat and vibration in the water are detected, and the possible leakage points are calculated and analyzed. When the anti-seepage core board plays a role in the formation, it can effectively isolate the soil and groundwater on both sides, and at the same time conduct heat and vibration as a uniform medium. Once leakage occurs, the water flow will pass through the channel formed by the anti-seepage core board to pass through both sides, resulting in a significant change in the conduction mode of heat and vibration, making it easy to identify the leakage location.

[0074] The anti-seepage core plate body 1 itself serves as a structural support, and there is no need to set up H-shaped steel or other foundation piles and other structural supports. Therefore, the anchor rod 6 can increase the structural strength of the body 1, and at the same time increase the bonding degree between the anti-seepage core plate and the surrounding soil, which is convenient for the optical fiber to detect the changes in the surrounding environment of the anti-seepage core plate. The wing plate 3 is designed to be smaller, which can reduce the overall thickness of the anti-seepage wall. At the same time, the overall design of the anti-seepage core plate takes into account both rigidity and flexibility, adapts to complex geological conditions, and ensures long-term stable operation.

[0075] The flexible anti-seepage wall also includes a cement wall 10, which can be an underground continuous wall / cement continuous wall, etc. The cement continuous wall is tightly combined with the anti-seepage core board to form a double intelligent protection system.

[0076] Step 1: According to the equipment weight requirements of the TRD method, after completing the precise setting out of the center line of the anti-seepage wall, a series of reinforcement measures such as laying steel plates are immediately implemented on the construction site to ensure that the site can bear the weight of the mechanical equipment and ensure the stability of the pile driver during operation. An excavator is used to excavate the working trench along the parallel track of the center line of the anti-seepage wall. The width of the trench is set to about 0.6 meters, and the depth needs to exceed 1.0 meters.

[0077] Step 2: First, determine the cement content and pre-mix the cement slurry based on the geological survey report; during construction, adjust the cement content according to the distribution of different soil layers in each work section.

[0078] Inject excavation fluid at the bottom of the cutting box to pre-cut the soil layer for a certain distance, then withdraw the excavation to the original position, start solidifying liquid to force it to mix and stir with the original soil, and form an underground continuous cement soil wall of equal thickness.

[0079] Step 3: Insert high-strength anti-seepage core board.

[0080] After the construction reaches a certain working surface, the high-strength anti-seepage core plate is inserted. The high-strength anti-seepage core plate must be kept vertical and inserted vertically into the cement soil mixing pile. The verticality deviation of the inserted high-strength anti-seepage core plate shall not be greater than 1 / 300, and the insertion time must be controlled within 3 hours after the completion of the mixing wall construction.

[0081] The anti-seepage core board has multiple anchor rods added on the surface, which is more conducive to combining with the soil, concrete, cement soil and other media on both sides compared to the smooth surface of the existing board.

[0082] Flexible anti-seepage wall formation: The thickness of the cement underground continuous wall is 350mm or 400mm. Compared with the traditional cement continuous wall with a thickness of about 1m, the thickness is reduced. Setting an anti-seepage wall on the dam has less impact on the dam itself.

[0083] After a large number of experimental verifications, the use of equal-thickness cement continuous walls with a thickness of 300mm to 450mm and anti-seepage core boards with a thickness of 90mm to 150mm can effectively realize the anti-seepage function in the dam, while having little impact on the dam structure itself.

[0084] like Figure 3 , Figure 4 As shown, when the main board 2 is arranged close to the anti-seepage side, the thickness of the cement wall 10 is 350 mm; if the main board 2 is alternately arranged on the anti-seepage side or opposite to it, the thickness of the cement wall 10 is 400 mm.

[0085] like Figure 5 , Figure 6As shown, in actual application, the flexible anti-seepage wall is constructed at the top center of the dam 30, located between the anti-seepage core plate body 1 and the cement wall 10, effectively covering the water level variation range of the river surface 20 to prevent leakage. The dam 30 itself serves as a support for the flexible anti-seepage wall, and can remain intact without dam collapse in the absence of water seepage.

[0086] The existing technology is that when a single anti-seepage core plate is constructed, the disturbance to the embankment is too large; the single TRD method construction equipment is heavy, the groove width is large, the damage to the embankment is large, and the anti-seepage effect is poor; the SMW method has poor integrity and poor anti-seepage performance. To address the above problems, a narrow groove is opened, cement soil is mixed in situ, and an anti-seepage core plate is inserted separately to realize the TPD process of composite flexible anti-seepage wall construction.

[0087] For complex strata, the TPD method needs to optimize the cement slurry ratio to ensure the uniformity and strength of the wall. At the same time, the anti-seepage core board structure can also be optimized.

[0088] The present invention: 1. After the anti-seepage core plate forms a wall in the soil layer, stress is generated inside. The optical fiber inside the sheet pile senses compression and tension, which are received by the transceiver receiver at the upper end and sent to the decoder at the upper end for decoding and analysis, forming the stress change inside the soil when the anti-seepage core plate is used. 2. The optical fiber on the outer surface of the anti-seepage core plate is compared with the position difference and stress analysis of the optical fiber at the active end to monitor relative movement analysis. 3. The optical fiber on the outer surface of the anti-seepage core plate is used for sound monitoring and temperature difference monitoring to analyze water seepage.

[0089] The present invention and its embodiments are described schematically above, which is not restrictive. The drawings show only one embodiment of the method of the present invention, which is not limited thereto. Therefore, if a person skilled in the art is inspired by the invention and creatively designs methods and embodiments similar to the technical solution without departing from the purpose of the invention, they should all fall within the protection scope of the present invention.

Claims

1. A construction method for a composite flexible anti-seepage wall of a dam, characterized in that: include: Step 1: Measurement and positioning, marking the coordinates of the corner points of the center line of the cut-off wall on the top of the dam, and using the excavation mechanism to excavate the working trench along the parallel trajectory of the center line of the cut-off wall; Step 2: Equipment is in place, and the construction machine equipment is transported to the top working position of the dam; Step 3: Construction method wall, using a construction machine to cut along the working groove to the designed depth, and forcibly mix and stir the original soil and solidifying liquid to form an underground continuous wall of equal thickness cement soil; Step 4: inserting the anti-seepage core plate. After the construction reaches a working surface larger than the width of the anti-seepage core plate, insert the anti-seepage core plate in the middle of the cement underground continuous wall. The bottom of the anti-seepage core plate is inserted to the designed depth. When multiple anti-seepage core plates are inserted, they are connected with adjacent anti-seepage core plates to form a composite flexible anti-seepage wall of the dam. The anti-seepage core plate comprises a body (1), the body (1) comprising a plate-shaped main board (2) and wing boards (3) arranged on both sides of the main board (2), the wing boards (3) being provided with connection ends, comprising optical fibers (71) and transceivers (72) connected to the upper ends of the optical fibers (71), a plurality of optical fibers (71) being distributed inside or / and on the outer surface of the body (1), the optical fibers (71) extending downward along the length direction of the body (1) and being used to monitor environmental changes of the body (1) and / or the surrounding underground continuous wall.

2. The construction method of a composite flexible anti-seepage wall of a dam according to claim 1, characterized in that: The surface of the main plate (2) is provided with a plurality of anchor rods (6) extending along the length direction of the main plate (2), the anchor rods (6) comprising a main rod (61) and a connecting portion (62), the connecting portion (62) connecting the main rod (61) and the main plate (2), the anchor rods are evenly and staggeredly distributed on both sides of the anti-seepage core plate, and after the anti-seepage core plate is inserted into the underground continuous wall, the anchor rods are anchored and combined with the underground continuous wall.

3. The construction method of a composite flexible anti-seepage wall of a dam according to claim 2, characterized in that: The cross-sectional width of the main rod (61) is greater than the cross-sectional width of the connecting portion (62), or the diameter of the main rod (61) is greater than twice the width of the connecting portion (62).

4. The construction method of a composite flexible anti-seepage wall of a dam according to claim 2, characterized in that: It comprises an optical fiber (71) arranged between the main rod (61) and the main board (2) and close to the connecting portion (62).

5. The construction method of a composite flexible anti-seepage wall of a dam according to claim 4, characterized in that: The distance between the top end of the anchor rod (6) and the surface of the main board (2) is greater than the thickness of the main board (2).

6. The construction method of a composite flexible anti-seepage wall of a dam according to claim 1, characterized in that: The connecting end comprises a first connecting end (4) and a second connecting end (5); the first connecting end (4) comprises a first end plate (41) and a male head (42); the second connecting end (5) comprises a second end plate (51) and a female head (52); an optical fiber (71) is arranged on the first end plate (41) or the second end plate (51), or an optical fiber (71) is arranged on the male head (42) or the female head (52).

7. A construction method for a composite flexible anti-seepage wall of a dam according to any one of claims 1 to 6, characterized in that: In step 3, the thickness of the underground continuous wall is 30cm to 45cm; In step 4, the inserted anti-seepage core plate has an overall thickness of 10 cm to 15 cm, and the anti-seepage core plate is disposed as a whole in the middle of the width of the underground continuous wall.

8. The construction method of a composite flexible anti-seepage wall of a dam according to claim 7, characterized in that: The width of the working trench is set at 0.5 to 0.7 m, while the depth needs to exceed 1.0 m.

9. The construction method of a composite flexible anti-seepage wall of a dam according to claim 1, characterized in that: In step three, the cement content is adjusted according to the average bonding strength of the soil layer. The cement content is controlled between 5% and 15%, and the cement soil strength is between 5% and 60% of the original soil layer strength.

10. The construction method of a composite flexible anti-seepage wall of a dam according to claim 9, characterized in that: The vertical deviation of the anti-seepage core plate insertion is less than or equal to 1 / 300. Lift the first anti-seepage core plate and insert it into the cement soil slurry to keep it in the middle until the top of the anti-seepage core plate is 0.8m to 1m higher than the slurry; lift the second anti-seepage core plate and sleeve the joints to connect the two anti-seepage core plates to each other until the top of the anti-seepage core plate is 0.8m to 1m higher than the slurry; Then re-press the first anti-seepage core board until it is 0.2m higher than the slurry; when inserting the board, ensure that the cement soil has not initially set.

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