Sinking method for layered uniform earth cutting and dynamic deviation correction of open caisson

Abstract

The invention discloses a sinking method for layered uniform earth cutting and dynamic deviation correction of an open caisson, and relates to the technical field of sinking construction of open caiss.The sinking method for layered uniform earth cutting and dynamic deviation correction of the open caisson comprises the steps that earth cutting construction is conducted according to the soil texture type of a soil layer where the open caisson is located; in the soft soil layer, an in-well layered earth cutting mode is adopted, an earth embankment is reserved at the cutting edge of the open caisson, and the earth embankment is gradually flattened to enable the open caisson to sink; in the hard soil layer, a groove jumping method is adopted for earth cutting, firstly, the blade foot area of the open caisson is emptied in a segmented mode, gravel is backfilled, and finally the soil layer below the positioning bearing pad is excavated away; and in the sinking process of the open caisson, the inclination state of the open caisson is monitored in real time, and when it is detected that the posture of the open caisson is inclined, dynamic deviation correction operation is executed. According to the method, the soil texture type of the soil layer where the open caisson is located is systematically distinguished, differentiated earth cutting construction strategies are designed for the soft soil layer and the hard soil layer correspondingly, and the sinking process of the open caisson is accurately controlled in combination with collaborative application of real-time monitoring and a dynamic deviation correction mechanism.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of sinking well sinking construction, in particular to a sinking well layered uniform earth excavation and dynamic deviation correction sinking method. BACKGROUND

[0002] With the continuous acceleration of urbanization and the continuous expansion of infrastructure construction, the demand for the development and utilization of underground space is increasingly prominent. As a historical and key underground structure construction technology, the sinking well is widely used in subway stations, pump rooms, underground pipe corridors and bridge foundations and other engineering scenarios.

[0003] In actual operation, the existing technology has obvious short boards in soil adaptability: there is no standardized process and fine control index for the earth excavation operation of soft soil and hard soil layer, and the construction personnel rely too much on subjective experience, which makes it difficult to accurately control the excavation depth, layer thickness and excavation sequence, and easily causes uneven stress distribution of the sinking well, imbalance of sinking rate and other phenomena, and further induces tilting accidents. SUMMARY

[0004] The main purpose of the present application is to provide a sinking well layered uniform earth excavation and dynamic deviation correction sinking method, which aims to solve the technical problems of lack of systematic earth excavation specification, lagging deviation correction measures and insufficient adaptability in complex geological conditions in the prior art.

[0005] To achieve the above purpose, the sinking well layered uniform earth excavation and dynamic deviation correction sinking method provided by the present application comprises: According to the soil type of the soil layer where the sinking well is located, the earth excavation construction is carried out; wherein the soil type includes soft soil layer and hard soil layer; In the soft soil layer, the layered earth excavation method in the well is adopted, and a soil embankment is reserved at the blade foot of the sinking well, and the soil embankment is gradually flattened to make the sinking well sink; wherein the blade foot is a sharp structure at the bottom of the sinking well, used to cut into the soil body; In the hard soil layer, the earth excavation is carried out by the skip method, the blade foot area of the sinking well is first excavated in sections, and then backfilled with sand and gravel, and finally the soil layer under the positioning cushion is excavated; In the process of sinking the sinking well, the inclination state of the sinking well is monitored in real time, and when the attitude inclination of the sinking well is detected, the dynamic deviation correction operation is performed; wherein the dynamic deviation correction operation includes at least one of the measures of decreasing the excavation depth from the high side to the low side of the sinking well, applying pressure on the high side of the sinking well, or spraying water on the slow side of the sinking well.

[0006] In an embodiment, in the soft soil layer, the step of sinking the open caisson by gradually flattening the soil embankment reserved at the cutting edge of the open caisson comprises: Symmetrically removing soil from the middle of the well hole of the open caisson to the cutting edge of the open caisson, with a layer thickness controlled within 30 cm; When the cutting edge is sunk to be substantially level with the soil surface of the middle of the well of the open caisson, first sink 40-50 cm in the middle of the well, and then uniformly expand the excavation to the periphery; Layered excavation of the soil platform inside the cutting edge to sink the open caisson, wherein the width of the soil platform is 20 cm, and the height is consistent with the design elevation of the cutting edge.

[0007] In an embodiment, in the hard soil layer, the step of sinking the open caisson by first segmenting the cutting edge area of the open caisson and backfilling with gravel, and finally excavating the soil layer under the positioning cushion comprises: Segmented excavation of the cutting edge area of the open caisson, with each segment having a length of 1-2 m, and immediately backfilling with gravel after excavation; wherein the components of the gravel include, in mass parts: 80-100 parts of quartz sand, 20-30 parts of gravel, and 10-15 parts of clay; Repeat the steps of segmented excavation and backfilling until all the cutting edge areas are processed; Excavate the soil layer under the positioning cushion in one go; wherein the positioning cushion is a concrete cushion layer with a thickness of 20 cm.

[0008] In an embodiment, when the dynamic correction operation is to gradually decrease the excavation depth from the high side to the low side of the inclination of the open caisson; In the process of sinking the open caisson, the inclination state of the open caisson is monitored in real time, and when the attitude of the open caisson is detected to be inclined, the step of performing dynamic correction operation comprises: Measure the elevations of the four corners of the open caisson by total station instrument, calculate the height difference, and determine the inclination direction and high-low side of the open caisson; Start excavating at the high side of the inclination, and gradually expand to the low side, with the excavation depth decreasing from the high side to the low side at a gradient of 5-10 cm per meter, so that the two ends of the open caisson remain at the same level.

[0009] In an embodiment, when the dynamic correction operation is to apply weight on the high side of the open caisson; In the process of sinking the open caisson, the inclination state of the open caisson is monitored in real time, and when the attitude of the open caisson is detected to be inclined, the step of performing dynamic correction operation comprises: Place a heavy object on the higher area at the top of the open caisson; wherein the heavy object is a concrete block or a steel ingot, with a weight of 5-10 tons; Real-time monitoring the sinking speed of the caisson, when the deviation is close to the normal position, removing or reducing the weight; wherein the normal position refers to the axis deviation of the caisson is less than 10mm.

[0010] In an embodiment, when the dynamic deviation operation is to spray water on the slow side of the caisson sinking; During the sinking of the caisson, the inclination state of the caisson is monitored in real time, and when the attitude inclination of the caisson is detected, the step of performing dynamic deviation operation includes: The water spraying pipe is installed on the slow side of the caisson sinking; wherein the water spraying pipe includes a high-pressure water pump, a water delivery hose and a nozzle, and the diameter of the nozzle is 10mm-20mm; Injecting pressure water, the water pressure is controlled at 0.6MPa-1.0MPa, so that the soil at this position becomes mud, reducing the friction; When the deviation is close to the normal position, stop spraying water, and fill the gap between the caisson outer wall and the soil with fine sand; wherein the compaction degree of the fine sand is not less than 0.93.

[0011] In an embodiment, according to the soil type of the soil layer where the caisson is located, before the step of excavating, the sinking method of the caisson layer-by-layer uniform excavation and dynamic deviation further includes: Before the sinking of the caisson, use the underground pipeline detector to detect the caisson and the surrounding 5m range, determine the soil layer distribution and soil parameters, and obtain the survey results; According to the survey results, determine the soil type of the soil layer where the caisson is located.

[0012] In an embodiment, before the sinking of the caisson, use the underground pipeline detector to detect the caisson and the surrounding 5m range, determine the soil layer distribution and soil parameters, and obtain the survey results, the step includes: Check against the surrounding pipeline drawings to determine the pipeline location; Use the underground pipeline detector to detect the pipeline within the caisson range, and migrate or reinforce the pipeline that affects construction; According to the detection results, draw the underground pipeline distribution map as the basis for construction.

[0013] In an embodiment, during the sinking of the caisson, the inclination state of the caisson is monitored in real time, and when the attitude inclination of the caisson is detected, the step of performing dynamic deviation operation includes: Use the monitoring system to measure the elevation, axis displacement and inclination of the caisson in real time, and increase the monitoring frequency to once an hour after the sinking is stable; wherein the monitoring system includes a total station, a level and a theodolite.

[0014] In an embodiment, the monitoring system is used to measure the elevation, axis displacement and inclination of the caisson in real time, and after the step of increasing the monitoring frequency to once per hour when the sinking is stable, the sinking method of layered uniform excavation and dynamic correction of the caisson further comprises: When the daily variation of the caisson settlement exceeds ±3mm or the cumulative settlement exceeds ±10mm, an alarm is triggered and the construction parameters are adjusted; wherein, adjusting the construction parameters includes increasing the excavation frequency, adjusting the correction measures or suspending the construction.

[0015] The technical solution of the present application systematically distinguishes the soil type of the soil layer where the caisson is located, and designs differentiated excavation construction strategies for soft soil layer and hard soil layer respectively, combined with the cooperative application of real-time monitoring and dynamic correction mechanism, to realize the accurate control of the sinking process of the caisson. Specifically, in the soft soil layer, the method of layered excavation in the well and the method of reserving soil embankment at the blade foot and gradually flattening are used to realize uniform stress and smooth sinking by using the easy deformation characteristics of soft soil; in the hard soil layer, the strategy of jump trenching, segmented emptying and backfilling of gravel is used to reduce the excavation difficulty and maintain the temporary support, avoiding structural instability. Since this scheme no longer relies on traditional experience-based judgment, but establishes systematic construction specifications for different geological conditions, it can effectively avoid the problems of uneven stress and inclination caused by inaccurate control of excavation depth and sequence, significantly improving the controllability and standardization level of construction, and reducing the dependence on the experience of construction personnel. In addition, by monitoring the inclination state of the caisson in real time and immediately performing dynamic correction operations (including reducing the excavation depth, applying weight or water jetting the outer wall) when the attitude deviation is detected, the transformation from passive after-the-fact remedy to active real-time regulation is realized, no longer waiting until the inclination is large before taking measures, but intervening precisely at the initial deviation stage, greatly improving the timeliness, accuracy and effectiveness of correction, while reducing the difficulty of correction, ensuring the stability, quality and safety of caisson construction. BRIEF DESCRIPTION OF DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0017] Figure 1 The flowchart of the sinking method of layered uniform excavation and dynamic correction of the caisson according to an embodiment of the present application is shown in the figure.

[0018] The implementation, functional characteristics and advantages of the present application will be further described with reference to the embodiments and the accompanying drawings. DETAILED DESCRIPTION

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0020] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly.

[0021] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the use of "and / or" or "and / or" throughout the text includes three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0022] With the continued acceleration of urbanization and the expansion of infrastructure construction, the demand for the development and utilization of underground space is becoming increasingly prominent. Caissons, as a long-standing and crucial underground structure construction technique, are widely used in engineering scenarios such as subway stations, pump rooms, underground utility tunnels, and bridge foundations.

[0023] In practice, existing technologies have obvious shortcomings in terms of soil adaptability: the excavation operation for soft soil and hard soil layers lacks standardized procedures and refined control indicators. Construction personnel rely too much on subjective experience and judgment, which makes it difficult to accurately control the excavation depth, layer thickness and excavation sequence. This can easily lead to uneven stress distribution and unbalanced sinking rate of the caisson, which in turn can induce tilting accidents.

[0024] To address this technical problem, this invention proposes a method for sinking a caisson by layered, uniform excavation and dynamic correction.

[0025] Please see Figure 1 In one embodiment of the present invention, the sinking method of the caisson with layered uniform excavation and dynamic correction includes: S10, performing earth excavation according to a soil type of the soil layer where the caisson is located; wherein the soil type includes a soft soil layer and a hard soil layer; S20, in the soft soil layer, using an in-well layered earth excavation method, reserving a soil embankment at a cutting edge of the caisson, and gradually flattening the soil embankment to sink the caisson; wherein the cutting edge is a sharp structure at the bottom of the caisson for cutting into the soil body; S30, in the hard soil layer, using a jump trench method to excavate, first segmentally excavating the cutting edge area of the caisson, and then backfilling with sand and gravel, and finally excavating the soil layer under the positioning cushion; S40, during the sinking of the caisson, real-time monitoring the inclination state of the caisson, and when the inclination state of the caisson is detected, performing a dynamic correction operation; wherein the dynamic correction operation includes at least one of decreasing the excavation depth from the high side to the low side of the caisson, applying a weight on the high side of the caisson, or water jetting on the slow sinking side of the caisson.

[0026] In practical applications, the soil type of the soil layer where the caisson is located can be understood as the classification of the physical properties of the soil body determined according to the geological exploration results, which can be obtained by means of drilling sampling, laboratory analysis or field test. For example, the compactness of the soil body is determined by the standard penetration test, or the bearing capacity of the soil body is evaluated by the static cone penetration test, so as to distinguish the soft soil layer and the hard soil layer. Further, when the in-well layered earth excavation method is used in the soft soil layer, the layered thickness can be realized by artificial marking or mechanical control, for example, using the depth sensor equipped with the excavator to realize real-time monitoring, so as to ensure that the thickness of each layer of excavation is uniform. In addition, the operation of reserving the soil embankment can be controlled by the pre-set elevation line, for example, setting a temporary baffle at the cutting edge to form the soil embankment, and then gradually flattening by artificial or small mechanical.

[0027] When the jump trench method is used for excavation in the hard soil layer, the length of the segmental excavation can be divided by measuring tools, for example, using a laser range finder to mark the boundary of each segmental excavation area. Further, the operation of backfilling with sand and gravel can be realized by using a mixture of aggregates with different particle sizes, for example, mixing crushed stone and fine sand in a certain proportion for backfilling, so as to enhance the temporary supporting capacity of the cutting edge area. The excavation of the soil layer under the positioning cushion can be completed by a small excavator or manual shovel, and the specific operation can be selected according to the site conditions.

[0028] The inclination state of the caisson can be monitored in real time by various technical means, such as installing an inclination sensor or using a total station to periodically measure the elevations of the four corners of the caisson. Further, the decreasing excavation depth in dynamic correction operation can be achieved by adjusting the angle of the excavator arm or replacing excavators of different specifications. The operation of applying weight on the high side of the caisson can be completed by placing prefabricated concrete blocks at the specified location using hoisting equipment, while the water jet operation can be achieved by connecting a nozzle to a high-pressure water pump, and the position and angle of the nozzle can be adjusted as needed.

[0029] The innovation of the present application is to solve the inclination risk caused by changes in geological conditions in caisson construction by systematically distinguishing soil types and matching targeted excavation methods, combined with real-time monitoring and dynamic correction mechanisms. Specifically, separate construction strategies for soft soil layer and hard soil layer are designed for layered excavation and jump method excavation, avoiding the problem of inaccurate control of excavation depth and sequence in traditional experience-based construction. At the same time, by monitoring the inclination state of the caisson in real time and triggering the coordinated application of various correction measures, a transition from passive remediation to active regulation is achieved, significantly improving the timeliness and accuracy of correction. Overall, the scheme effectively addresses the core problems of lack of flexibility in construction methods and lag in correction mechanisms under complex geological conditions.

[0030] The working principle of the embodiment of the present application is as follows: the soil type of the soil layer where the open caisson is located is systematically distinguished, different excavation construction methods are adopted for soft soil layer and hard soil layer respectively, and real-time monitoring and dynamic correction mechanism are combined to realize accurate control of the open caisson sinking process. Specifically, in the soft soil layer, the layered excavation method in the well is adopted, and a soil embankment is reserved at the cutting foot of the open caisson, and the soil embankment is gradually flattened to make the open caisson sink stably. This method takes advantage of the characteristics of soft soil that is easy to deform, and through layered control and gradual flattening operation, the problem of excessive sinking speed or local stress concentration caused by one-time excavation is avoided, thereby ensuring uniform stress and stable sinking of the open caisson in the soft soil layer. Further, in the hard soil layer, the method of jumping trough is adopted, that is, the cutting foot area of the open caisson is first excavated in sections and backfilled with gravel, and finally the soil layer under the positioning cushion is excavated. This method reduces the difficulty of excavation in hard soil layer by excavating in sections and backfilling with gravel in time, and maintains temporary support in the cutting foot area through gravel filling to prevent overall structure instability. At the same time, during the sinking process of the open caisson, the inclination state is monitored in real time, and when the inclination state is detected, dynamic correction operation is immediately performed. The dynamic correction operation includes at least one of the following measures: gradually decreasing the excavation depth from the high side to the low side of the open caisson, applying pressure on the high side of the open caisson, or water jetting on the slow sinking side of the outer wall of the open caisson. These measures can adjust the soil resistance distribution, actively balance the stress of the open caisson, or quickly reduce the soil friction resistance, thereby realizing the transformation from passive remedy to active control. Therefore, through the organic integration of soil classification, layered excavation control and dynamic correction, the technical scheme solves the core problems of lack of flexibility of construction method and lag of correction mechanism under complex geological conditions, effectively deals with the inclination risk caused by changes in geological conditions, and ensures the stability and safety of open caisson construction.

[0031] In the embodiment of the present application, in the soft soil layer, the step of adopting the layered excavation method in the well and reserving a soil embankment at the cutting foot of the open caisson, and gradually flattening the soil embankment to make the open caisson sink, includes: S21, uniformly and symmetrically removing soil from the middle of the well hole to the cutting foot of the open caisson, with the layered thickness controlled within 30 cm; S22, when the cutting foot sinks to be substantially level with the middle soil surface of the open caisson, first sinking 40-50 cm in the middle of the well, and then uniformly expanding excavation around; S23, layered excavation of the soil platform inside the cutting foot to make the open caisson sink, wherein the width of the soil platform is 20 cm, and the height is consistent with the design elevation of the cutting foot.

[0032] Specifically, the layering thickness refers to the vertical height of each layer of soil when excavating in the soft soil layer, and the purpose is to avoid the instability of the open caisson caused by the rapid stress release by limiting the single excavation depth. In practical application, the layering thickness can be realized by using mechanical excavation equipment combined with manual finishing, ensuring that the excavation depth is strictly controlled within 30 cm each time, thereby effectively reducing the influence of soil stress mutation on the open caisson structure. Among them, uniform and symmetrical soil removal refers to keeping the consistency of the excavation amount and rate on both sides when excavating from the center of the open caisson well to the blade foot direction, and the purpose is to prevent eccentric load caused by asymmetric excavation, thereby avoiding the inclination of the open caisson. In addition, the soil platform refers to a specific soil structure inside the blade foot of the open caisson for supporting the open caisson and controlling the sinking speed, which can be determined by accurate measurement and marking to ensure that the width is 20 cm and the height is consistent with the design elevation of the blade foot, thereby realizing accurate control of the sinking process of the open caisson.

[0033] In detail, during the construction process in the soft soil layer, first, uniform and symmetrical layering excavation is performed from the middle of the open caisson well to the blade foot, and this process can effectively avoid the risk of soil stress concentration or sudden sinking of the open caisson caused by excessive excavation at one time by strictly controlling the layering thickness within 30 cm. When the blade foot sinks to the level of the soil surface in the middle of the well, a sinking point is first created in the middle of the well, i.e., sinking 40 cm to 50 cm first, and then uniformly expanding excavation around, and this operation sequence can guide the open caisson to form a central sinking trend, thereby balancing the stress distribution at the bottom and reducing the possibility of soil collapse at the blade foot. On this basis, by layering and removing the soil platform inside the blade foot with a width of 20 cm and a height consistent with the design elevation, the uniformity and stability of the open caisson during sinking can be further ensured. The above technical solution converts the empirical excavation into a quantifiable operation process by systematically controlling the excavation sequence, layering parameters, and soil platform size, significantly improving the controllability and uniformity of the sinking of the open caisson in the soft soil layer.

[0034] In summary, through the above technical solution, not only the technical problem of uneven sinking of the open caisson in the soft soil layer is solved, but also a flexible and systematic coping strategy for construction under complex geological conditions is provided, thereby improving the construction efficiency, engineering quality, and safety.

[0035] In the embodiment of the present application, in the hard soil layer, the jump trench method is used for excavation, the blade foot area of the open caisson is first excavated in sections, and then the sand and gravel is backfilled, and finally the soil layer under the positioning cushion is excavated. S31, excavating the blade foot area of the open caisson in sections, each section has a length of 1 m to 2 m, and immediately after excavation, sand and gravel is backfilled; wherein the components of the sand and gravel include, in mass parts: 80 to 100 parts of quartz sand, 20 to 30 parts of gravel, and 10 to 15 parts of clay; S32, repeating the segment hollowing and backfilling steps until all the regions of the blade foot are processed; S33, removing the soil layer under the positioning bearing pad at one time; wherein the positioning bearing pad is a concrete pad layer with a thickness of 20 cm.

[0036] Specifically, the blade foot region refers to the sharp structure part at the bottom of the open caisson for cutting into the soil body, and the hollowing operation needs to strictly control the single range to ensure construction safety. The hollowing length is limited to 1m-2m, which can ensure construction efficiency and effectively avoid the problem of local stress concentration caused by too large hollowing range. The gravel, as a kind of composite backfill material, has a clear functional orientation in the design of its ratio. The quartz sand provides the main skeleton support function, the gravel enhances the overall strength, and the appropriate clay plays the role of adhesion and compressibility adjustment. The positioning bearing pad, as a temporary support structure during the sinking of the open caisson, has a thickness of 20 cm, which is determined based on construction experience and structural stress analysis.

[0037] In detail, the technical scheme realizes the stable sinking of the open caisson in the hard soil layer through a series of ordered operation steps. Firstly, when segment hollowing is carried out in the blade foot region, the length of each segment is strictly controlled within 1m-2m. This segmented method can effectively disperse the stress generated during construction and avoid local stress concentration. Then, the gravel backfilling operation not only fills the hollowed area in time, but also forms a support system with sufficient strength and appropriate compressibility through the specific ratio of gravel material. The hollowing and backfilling steps are repeated until the entire blade foot region is processed, ensuring the uniformity of the stress of the soil body around the open caisson. Finally, when all the blade foot regions are processed, the soil layer under the positioning bearing pad is removed at one time. This operation method avoids the risk of tilting of the open caisson caused by segmented removal, thereby ensuring the smooth sinking of the open caisson.

[0038] Through the above technical scheme, the problem of instability of the soil body in the blade foot region during the sinking process of the open caisson in the hard soil layer is effectively solved, and the uniformity and stability of the sinking of the open caisson are realized. Especially in complex geological conditions, this method can flexibly cope with the alternating situation of soft and hard soil layers, improving the construction efficiency and engineering quality.

[0039] In the embodiment of the present application, when the dynamic correction operation is to decrease the excavation depth from the high side to the low side of the inclination of the open caisson; During the sinking of the open caisson, the inclination state of the open caisson is monitored in real time, and when the attitude inclination of the open caisson is detected, the step of performing dynamic correction operation includes: S41, measuring the elevations of the four corners of the open caisson by a total station instrument, calculating the height difference, and determining the inclination direction and high-low side of the open caisson; S42, starting to dig on the side with higher inclination, and gradually expanding to the side with lower inclination, the digging depth decreases from the higher side to the lower side, the decreasing gradient is 5cm-10cm per meter, so that the two ends of the caisson remain at the same level.

[0040] Wherein, the total station refers to a high-tech measuring instrument integrating light, machine and electricity, which can be realized by using electronic distance measurement and angle measurement integrated equipment, aiming to provide accurate elevation and height difference data, and ensure the accuracy of inclination direction and high-low side judgment. The digging depth decreasing gradient refers to the change rate of gradually reducing the digging depth from the high side to the low side, which can be controlled by pre-set construction parameters or automatic digging equipment, aiming to coordinate the sinking rate of the two sides of the caisson, and avoid the problem of stress imbalance caused by uneven local digging.

[0041] Specifically, by measuring the elevations of the four corners of the caisson with the total station and calculating the height difference, the inclination state of the caisson can be objectively quantified, providing a scientific basis for subsequent correction operations. On this basis, digging starts from the side with higher inclination and gradually expands to the side with lower inclination. This design of digging sequence makes the stress distribution of the caisson more uniform, reducing the additional stress concentration phenomenon caused by sudden digging. At the same time, the digging depth decreases from the high side to the low side at a gradient of 5cm-10cm per meter. This standardized range ensures the continuity and smoothness of the change of digging depth, effectively balancing the sinking rate difference of the two sides of the caisson. Finally, through the above operations, the two ends of the caisson remain at the same level, realizing precise control of the dynamic correction process.

[0042] In addition, the scheme is combined with the aforementioned digging methods in soft soil layer and hard soil layer, further improving the overall stability and safety of caisson construction. For example, the digging method of reserving soil embankment in soft soil layer and gradually flattening it, combined with the decreasing digging depth in dynamic correction, can flexibly adjust the construction strategy under different soil conditions, thereby better addressing the caisson inclination problem in complex geological environment. Through the above technical scheme, not only the problem of lack of standardized control of digging depth decreasing gradient is solved, but also the controllability and correction effect of caisson sinking process are significantly improved, ensuring the engineering quality and construction safety.

[0043] In the embodiment of the application, when the dynamic correction operation is to apply a weight on the high side of the caisson; During the sinking of the caisson, the inclination state of the caisson is monitored in real time, and when the attitude inclination of the caisson is detected, the step of performing dynamic correction operation includes: S401, placing a weight on the higher area of the top of the caisson; wherein the weight is a concrete block or a steel ingot, and the weight is 5-10 tons; S402, real-time monitoring the sinking speed of the caisson, when the deviation is close to the normal position, removing or reducing the weight; wherein the normal position refers to the axis deviation of the caisson being less than 10 mm.

[0044] Specifically, the higher area at the top of the caisson refers to the part that is relatively higher after the caisson tilts, and its specific position can be determined by measuring equipment. In practical application, the weight can be a concrete block or a steel ingot, both of which have high density and stability and can provide stable weight effect. The weight range is set to 5-10 tons, which is a key parameter that balances between avoiding sudden sinking caused by excessive weight and being unable to effectively correct deviation due to insufficient weight. The purpose of real-time monitoring the sinking speed of the caisson is to change the deviation operation from passive response to active regulation, and to provide objective basis for subsequent operation by dynamically tracking the change of sinking speed. The definition of normal position is that the axis deviation of the caisson is less than 10 mm, which ensures that the termination point of deviation has a clear technical index.

[0045] In detail, this scheme realizes precise intervention on the tilted state of the caisson by placing weights in the higher area at the top of the caisson, based on the principle that the high side of the tilt needs additional pressure to balance the sinking speed. The step of real-time monitoring the sinking speed, combined with the quantitative standard of axis deviation less than 10 mm, forms a double verification system to ensure that the caisson terminates external intervention in time when it recovers to the vertical state. First, place weights in the higher area at the top of the caisson, use the stable pressure provided by concrete blocks or steel ingots to adjust the force balance on both sides of the caisson. Then, continuously monitor the change of sinking speed to dynamically evaluate the deviation effect, and decide whether to adjust the weight or position of the weight according to the monitoring data. When the axis deviation of the caisson gradually decreases and approaches the normal range, gradually remove or reduce the weight to avoid insufficient deviation caused by premature removal or excessive deviation caused by delayed removal. Overall, the steps are closely linked to form a closed-loop control mechanism, which converts the experience-driven weight operation into a quantifiable dynamic adjustment process, fundamentally improving the accuracy and reliability of deviation.

[0046] In addition, the above-mentioned scheme is combined with the aforementioned layered uniform excavation and dynamic deviation correction method, by introducing the quantitative standard and real-time monitoring mechanism of weight correction, further improving the deviation correction technology system in caisson construction, significantly improving the construction efficiency, engineering quality and safety.

[0047] In the embodiments of the present application, when the dynamic deviation correction operation is water jetting on the outer wall of the slow sinking side of the caisson; In the process of sinking the caisson, real-time monitoring the tilted state of the caisson, when detecting that the attitude of the caisson is tilted, the step of performing dynamic deviation correction operation includes: S410, installing the water jet pipe on the outer wall of the slow sinking side of the caisson; wherein the water jet pipe comprises a high-pressure water pump, a water delivery hose and a nozzle, and the diameter of the nozzle is 10mm-20mm; S420, injecting pressure water, and the water pressure is controlled at 0.6MPa-1.0MPa, so that the soil at the position becomes mud, and the frictional resistance is reduced; S430, when the deviation is corrected to approach the normal position, stopping the water injection, and filling the gap between the outer wall of the caisson and the soil with fine sand; wherein the compaction degree of the fine sand is not less than 0.93.

[0048] Specifically, the water jet pipe refers to a device for injecting high-pressure water flow to the soil of the outer wall of the caisson, which can be made of metal or high-strength plastic material to ensure that it can withstand the impact force of high-pressure water. The design of the nozzle diameter of 10mm-20mm aims to ensure that the water jet has appropriate concentration and impact force, which can efficiently scour the soil to form a uniform mud layer, and avoid the problems of water dispersion caused by too large nozzle or blockage caused by too small nozzle. In practical application, the water pressure is controlled within the range of 0.6MPa-1.0MPa, which is set based on the physical properties of the soil. This range can fully liquefy the soil to reduce the frictional resistance of the well wall and promote the sinking of the caisson, and prevent the soil structure from being damaged or the surrounding strata from being disturbed due to excessive water pressure, thereby ensuring the smooth transition of the correction process. The requirement that the compaction degree of the fine sand is not less than 0.93 is to effectively prevent soil loss and secondary inclination of the caisson by the rapid consolidation characteristics of the fine sand with high compaction degree, and to ensure the long-term stability of the structure after correction.

[0049] In detail, during the sinking process of the caisson, real-time monitoring of the inclination state of the caisson is the prerequisite for the entire correction operation. When the inclination of the caisson is detected, the water jet pipe needs to be installed on the outer wall of the slow sinking side first. The nozzle diameter of the water jet pipe is precisely designed to achieve precise control of soil liquefaction under different geological conditions. Then, the water pressure is controlled within the range of 0.6MPa-1.0MPa by the high-pressure water pump, and the pressure water is injected to liquefy the soil into mud, thereby significantly reducing the frictional resistance of the well wall and promoting the caisson to gradually return to the normal position. In this process, the selection of water pressure needs to consider the physical properties of the soil such as particle composition and density, to ensure that the liquefaction effect is moderate and does not cause excessive disturbance to the surrounding strata. When the caisson approaches the normal position, it is particularly important to stop the water injection and fill the gap between the outer wall and the soil with fine sand. The high compaction degree of the fine sand not only can quickly close the gap caused by water injection, but also can effectively prevent soil loss and secondary inclination of the caisson through its good consolidation performance. The above technical features work together to convert the traditional empirical water injection correction operation into a quantifiable and controllable precision process, significantly improving the reliability of caisson construction under complex geological conditions.

[0050] In addition, the scheme is closely combined with the overall process of the aforementioned layered uniform excavation and dynamic correction of the caisson. For example, when the layered excavation method is used in soft soil layers, if the caisson tilts, the water jet correction can be used to quickly adjust the posture; when the jump trench method is used in hard soil layers, the water jet correction can be used as an auxiliary means to optimize the sinking effect. This flexible combination of technologies enables the caisson construction to maintain high precision and safety under different geological conditions.

[0051] In the embodiments of the present application, before the step of excavating, the sinking method of layered uniform excavation and dynamic correction of the caisson further comprises: P10, before the sinking of the caisson, using an underground pipeline detector to detect the caisson and the surrounding 5m range to determine the soil layer distribution and soil quality parameters, and obtain the survey results; P20, determining the soil type of the soil layer where the caisson is located according to the survey results.

[0052] Wherein, the underground pipeline detector refers to a professional equipment for detecting the position, depth and related information of underground pipelines, which can be realized by electromagnetic induction detector, geological radar detector or acoustic detector. In actual application, the detection range is set to 5m around the caisson to ensure that the main body of the caisson and its key influence area are covered, and to avoid the blind area of survey caused by local soil layer mutation or underground pipeline interference. The determination process of soil layer distribution and soil quality parameters can accurately identify the vertical and horizontal distribution characteristics of the soil layer and the specific physical parameters, thereby providing a quantitative basis for subsequent construction decision-making.

[0053] Specifically, the systematic pre-geological survey link is introduced before the sinking of the caisson, which fundamentally solves the problem of inaccurate determination of soil type. This scheme replaces the traditional experience judgment with professional detection equipment, significantly improving the objectivity and comprehensiveness of soil information acquisition. In the implementation process, first, the underground pipeline detector is used to scan the soil layer within 5m around the caisson, generating detailed detection data. Then, through analysis and processing of these data, the vertical stratification structure, horizontal distribution characteristics and specific physical parameters of the soil layer are determined, such as the density, water content and shear strength of the soil body. Finally, according to these quantitative data, the soil type of the soil layer where the caisson is located is scientifically determined to ensure accurate differentiation between soft soil layers and hard soil layers. This method not only avoids the problems of uneven excavation and force imbalance caused by soil misjudgment, but also provides a reliable geological basis for subsequent excavation construction, ensuring the stability and safety of the caisson sinking process.

[0054] In addition, the above scheme is closely matched with the layered uniform excavation of the caisson and the dynamic deviation correction operation. Through accurate soil type determination, the excavation method can be reasonably selected, such as using layered excavation in soft soil layer and reserving a soil embankment at the blade foot, or using the skip method to excavate in hard soil layer and backfilling sand and gravel. At the same time, this pre-investigation means also provides an important reference for real-time monitoring and dynamic correction, making the correction measures more targeted and effective, thereby further improving the construction efficiency and engineering quality.

[0055] In the embodiment of the application, before the caisson is sunk, the caisson and the surrounding 5m range are detected using an underground pipeline detector to determine the soil layer distribution and soil quality parameters, and the step of obtaining the investigation result includes: P11, check the surrounding pipeline drawings to determine the pipeline position; P12, use an underground pipeline detector to detect the pipelines within the caisson range, and relocate or reinforce and protect the pipelines that affect construction; P13, draw an underground pipeline distribution map according to the detection results as a construction basis.

[0056] Specifically, the underground pipeline detector refers to a device that detects the position and depth of underground pipelines using electromagnetic induction, geological radar and other technical principles, which can be realized by using a handheld detector, a vehicle-mounted detection system or a drone-mounted detection device. Among them, the pipeline position refers to the specific distribution coordinates of the underground pipeline in space, which can be obtained by reflecting the characteristics of the detection signal, the magnetic field change rule and other ways. In addition, the underground pipeline distribution map is a technical document that presents the detected pipeline information in a graphical way, which aims to provide an intuitive reference for subsequent construction and avoid safety hazards caused by pipeline interference.

[0057] In detail, before the caisson construction, by checking the surrounding pipeline drawings, the known pipeline layout can be identified in advance, so as to effectively avoid the blind area problem that may be caused by relying only on field detection. On this basis, combined with the actual detection data of the underground pipeline detector, the pipeline state can be verified and the construction interference source can be processed in time, such as taking relocation measures for high-voltage cables or reinforcing and protecting water supply pipelines. These operations not only directly eliminate the risk of pipeline damage, but also ensure the continuity of on-site operations. At the same time, the underground pipeline distribution map drawn according to the detection results converts complex pipeline information into visual guidance, so that construction personnel can accurately avoid pipeline areas and avoid the randomness of experience judgment. The above scheme refines the operation specification of the detection steps to ensure the reliability of the investigation results and the safety of construction, solving the problem of lack of specific guidance in the detection process.

[0058] In summary, through the above technical solution, the detection step is changed from a general description to an executable standard process, effectively supporting the accurate acquisition of soil parameters and the scientific formulation of construction schemes, significantly improving construction efficiency and safety.

[0059] In the embodiment of the application, during the sinking of the open caisson, the inclination state of the open caisson is monitored in real time, and when the attitude inclination of the open caisson is detected, the step of performing dynamic correction operation includes: S411, using a monitoring system to measure the elevation, axis displacement and inclination of the open caisson in real time, and increasing the monitoring frequency to once an hour after sinking is stable; wherein the monitoring system includes a total station, a level and a theodolite.

[0060] Specifically, the monitoring system refers to a set of comprehensive equipment combination for obtaining three-dimensional state data of the open caisson, which can be realized by using multiple high-precision measuring instruments to work cooperatively. In practical application, the total station provides plane coordinate data to monitor the axis displacement, the level ensures the reliability of the elevation measurement, and the theodolite captures the change of the inclination angle. The selection and combination of these devices aims to form a multi-dimensional complementary monitoring system, covering the key parameters of the open caisson attitude and meeting different measurement needs.

[0061] In detail, the scheme significantly improves the attitude control ability in the sinking process of the open caisson by optimizing the monitoring mechanism. The introduction of the monitoring system realizes the continuous dynamic tracking of the elevation, axis displacement and inclination of the open caisson, avoiding the problem of missing small deviations that may accumulate in traditional intermittent measurement. In the stable sinking stage of the open caisson, the monitoring frequency is increased to once an hour, which strengthens the data acquisition density according to the characteristics of the slow movement of the open caisson, thereby effectively preventing the development of hidden deviations caused by too long monitoring interval. Based on the above monitoring data, the construction personnel can discover the inclination trend of the open caisson in time and intervene in the initial stage, providing sufficient time window for dynamic correction. In addition, the multi-device cooperative working mode of the monitoring system not only ensures the comprehensiveness and accuracy of the data, but also lays a reliable foundation for subsequent correction decision-making.

[0062] On this basis, the scheme is closely combined with the overall process of the aforementioned uniform layer-by-layer excavation and dynamic correction of the open caisson. Through real-time monitoring, the construction personnel can flexibly adjust the excavation strategy under different working conditions of soft soil layer and hard soil layer, and immediately take targeted correction measures such as adjusting the excavation depth, applying weight or water jetting the outer wall when the attitude of the open caisson is found to be abnormal. This close cooperation between monitoring and construction significantly improves the safety and efficiency of open caisson construction, solving the problem of delayed correction caused by untimely monitoring.

[0063] In the embodiment of the present application, the monitoring system is used to measure the elevation, axis displacement and inclination of the caisson in real time. After the step of increasing the monitoring frequency to once an hour when the sinking is stable, the method for uniform layering excavation and dynamic correction of the sinking of the caisson further comprises: S412, when the daily variation of the caisson settlement exceeds ±3mm or the cumulative settlement exceeds ±10mm, triggering an alarm and adjusting the construction parameters; wherein adjusting the construction parameters includes increasing the excavation frequency, adjusting the correction measures or suspending the construction.

[0064] Specifically, the daily variation of the settlement refers to the change value of the caisson sinking in a day, which can reflect the mutation of the short-term sinking rate and is used to capture the initial signs of uneven sinking. In practical application, high-frequency measurement can be performed by using total station, level and other devices to obtain accurate data. The cumulative settlement refers to the total change of the caisson sinking from the start of sinking to the current time, which can reflect the long-term deviation trend and provide a basis for judging the stability of the overall sinking. The purpose of the design of the alarm triggering mechanism is to convert the monitoring data into an immediate action signal to avoid the risks caused by the delay or negligence of manual response. The specific implementation of adjusting the construction parameters includes but is not limited to increasing the excavation frequency to accelerate the removal of soil, optimizing the excavation depth distribution or applying weight to correct the sinking trajectory, and suspending the construction in serious abnormal conditions to prevent the problem from getting worse.

[0065] In detail, the above technical solution realizes the active intervention in the sinking process of the caisson by establishing an automatic association mechanism between settlement abnormalities and construction responses. Specifically, when the monitoring system detects that the daily variation of the settlement exceeds ±3mm or the cumulative settlement exceeds ±10mm, the system will immediately trigger an alarm signal to prompt the construction personnel to take appropriate measures. At this time, according to the different degrees of abnormality, the excavation frequency can be increased to promote the balance of sinking, or the correction measures can be adjusted to directly correct the sinking trajectory. If the abnormality is serious, the construction can be suspended to gain time for subsequent processing. This multi-dimensional parameter adjustment strategy not only can respond quickly to slight abnormalities, but also can flexibly cope with various emergencies under complex geological conditions, thereby significantly improving the pertinence and controllability of correction. In addition, in combination with the aforementioned dynamic correction operation, this scheme can form a more perfect construction response system under different soil conditions, fundamentally solving the problem of disconnection between monitoring data and construction operation, and ensuring the stability and safety of the sinking process.

[0066] The above only describes exemplary embodiments of the present application, and does not limit the protection scope of the present application. Any equivalent structural transformation made by using the content of the present application specification and drawings, or direct / indirect application in other related technical fields is included in the protection scope of the present application.

Claims

1. A sinking method for sinking a caisson in layers with uniform excavation and dynamic correction, characterized in that, The sinking method of the caisson layer-by-layer uniform excavation and dynamic deviation correction comprises the following steps: According to the soil type of the soil layer where the caisson is located, the excavation construction is carried out; wherein the soil type includes soft soil layer and hard soil layer; In the soft soil layer, the layer-by-layer excavation method in the caisson is adopted, and a soil embankment is reserved at the blade foot of the caisson, and the soil embankment is gradually flattened to make the caisson sink; wherein the blade foot is a sharp structure at the bottom of the caisson, which is used to cut into the soil body; In the hard soil layer, the jump groove method is adopted to excavate, the blade foot area of the caisson is first excavated in sections, and then the sand and gravel are backfilled, and finally the soil layer under the positioning bearing pad is excavated; In the process of sinking the caisson, the inclination state of the caisson is monitored in real time, and when the attitude inclination of the caisson is detected, the dynamic deviation correction operation is performed; wherein the dynamic deviation correction operation includes at least one of the following measures: decreasing the excavation depth from the high side to the low side of the caisson, applying pressure on the high side of the caisson, or water jetting on the slow sinking side of the caisson.

2. The sinking method for sinking caisson in layers with uniform soil excavation and dynamic deviation correction according to claim 1, characterized in that, In the soft soil layer, the layer-by-layer excavation method in the caisson is adopted, and a soil embankment is reserved at the blade foot of the caisson, and the soil embankment is gradually flattened to make the caisson sink; the step comprises the following steps: Uniformly and symmetrically remove the soil from the middle of the well hole of the caisson to the blade foot of the caisson, and the layer thickness is controlled within 30 cm; When the blade foot sinks to the soil surface of the middle of the caisson, first sink 40-50 cm in the middle of the well, and then uniformly expand around; Excavate the soil platform inside the blade foot layer by layer to make the caisson sink; wherein the width of the soil platform is 20 cm, and the height is consistent with the design elevation of the blade foot.

3. The sinking method for sinking caisson in layers with uniform soil excavation and dynamic deviation correction according to claim 2, characterized in that, In the hard soil layer, the jump groove method is adopted to excavate, the blade foot area of the caisson is first excavated in sections, and then the sand and gravel are backfilled, and finally the soil layer under the positioning bearing pad is excavated; the step comprises the following steps: Excavate the blade foot area of the caisson in sections, each section is 1-2 m long, and immediately backfill sand and gravel after excavation; wherein the components of the sand and gravel include, in mass parts: 80-100 parts of quartz sand, 20-30 parts of gravel, and 10-15 parts of clay; Repeat the steps of section-by-section excavation and backfilling until all the blade foot areas are processed; Excavate the soil layer under the positioning bearing pad at one time; wherein the positioning bearing pad is a concrete pad layer with a thickness of 20 cm.

4. The sinking method for sinking caisson in layers with uniform soil excavation and dynamic deviation correction according to claim 3, characterized in that, When the dynamic deviation correction operation is to decrease the excavation depth from the high side to the low side of the caisson; In the process of sinking the caisson, the inclination state of the caisson is monitored in real time, and when the attitude inclination of the caisson is detected, the dynamic deviation correction operation is performed; wherein the dynamic deviation correction operation includes at least one of the following measures: decreasing the excavation depth from the high side to the low side of the caisson, applying pressure on the high side of the caisson, or water jetting on the slow sinking side of the caisson. The inclination direction and high-low side of the caisson are determined by measuring the elevations of the four corners of the caisson with a total station instrument, calculating the height difference, and determining the inclination direction and high-low side of the caisson; Start excavation on the high side of the inclination and gradually expand to the low side, with the excavation depth decreasing from the high side to the low side, and the decreasing gradient being 5-10 cm per meter, so that the two ends of the caisson remain on the same horizontal plane.

5. The sinking method for sinking caisson in layers with uniform soil excavation and dynamic deviation correction according to claim 3, characterized in that, When the dynamic deviation correction operation is to apply pressure on the high side of the caisson; During the sinking of the caisson, the inclination state of the caisson is monitored in real time, and when the attitude inclination of the caisson is detected, the step of performing dynamic correction operation comprises: A heavy object is placed at the higher area on the top of the caisson; wherein the heavy object is a concrete block or a steel ingot, and the weight is 5-10 tons; The sinking speed of the caisson is monitored in real time, and when the correction is close to the normal position, the heavy object is removed or reduced; wherein the normal position refers to the axis deviation of the caisson being less than 10 mm.

6. The sinking method for sinking caisson in layers with uniform soil excavation and dynamic deviation correction according to claim 3, characterized in that, When the dynamic correction operation is water jetting on the slow side outer wall of the caisson during sinking; During the sinking of the caisson, the inclination state of the caisson is monitored in real time, and when the attitude inclination of the caisson is detected, the step of performing dynamic correction operation comprises: The water jet pipe is installed on the slow side outer wall of the caisson during sinking; wherein the water jet pipe comprises a high-pressure water pump, a water delivery hose and a nozzle, and the diameter of the nozzle is 10-20 mm; Pressure water is injected, and the water pressure is controlled at 0.6-1.0 MPa, so that the soil at this position becomes mud, reducing the frictional resistance; When the correction is close to the normal position, the water jetting is stopped, and the gap between the caisson outer wall and the soil is filled with fine sand; wherein the compaction degree of the fine sand is not less than 0.

93.

7. The sinking method for layered uniform excavation and dynamic correction of caisson according to any one of claims 1 to 6, characterized in that, According to the soil type of the soil layer where the caisson is located, before the step of excavating, the sinking method of the caisson with layered uniform excavation and dynamic correction further comprises: Before the sinking of the caisson, an underground pipeline detector is used to detect the caisson and the surrounding area within 5 m to determine the soil layer distribution and soil parameters, and obtain the survey results; According to the survey results, the soil type of the soil layer where the caisson is located is determined.

8. The sinking method for sinking caisson in layers with uniform soil excavation and dynamic deviation correction according to claim 7, characterized in that, Before the sinking of the caisson, the step of using an underground pipeline detector to detect the caisson and the surrounding area within 5 m to determine the soil layer distribution and soil parameters, and obtain the survey results comprises: Contrast the surrounding pipeline drawings to determine the pipeline location; Use the underground pipeline detector to detect the pipelines within the caisson range, and relocate or reinforce the pipelines that affect construction; According to the detection results, draw an underground pipeline distribution map as a construction basis.

9. The sinking method for layered uniform excavation and dynamic correction of sinking caisson according to any one of claims 1 to 6, characterized in that, During the sinking of the caisson, the inclination state of the caisson is monitored in real time, and when the attitude inclination of the caisson is detected, the step of performing dynamic correction operation comprises: The elevation, axis displacement and inclination of the caisson are measured in real time by a monitoring system, and the monitoring frequency is increased to once an hour after sinking is stable; wherein the monitoring system comprises a total station, a level and a theodolite.

10. The sinking method for sinking caisson in layers with uniform soil excavation and dynamic deviation correction according to claim 9, characterized in that, After the step of measuring the elevation, axis displacement and inclination of the caisson in real time by a monitoring system, and increasing the monitoring frequency to once an hour after sinking is stable, the sinking method of the caisson with layered uniform excavation and dynamic correction further comprises: When the daily variation of the caisson settlement exceeds ±3 mm or the cumulative settlement exceeds ±10 mm, an alarm is triggered and the construction parameters are adjusted; wherein adjusting the construction parameters includes increasing the excavation frequency, adjusting the correction measures or suspending the construction.

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