A Numerical Simulation-Based Analysis Method and System for Rock-Embedded Water Stopping in Cofferdams of Strongly Weathered Rock Strata

Abstract

This invention discloses a numerical simulation-based method and system for analyzing the embedded rock waterproofing of cofferdams in strongly weathered rock strata. The method includes: constructing a three-dimensional geological model containing weathering gradients based on survey data; and setting up dedicated interface units at the contact surface between sheet piles and the rock strata. Through numerical calculation, the compressive stress on the rock mass side of the piles and the deflection deformation of the interlocking joints generated during pile driving are obtained. Combining the dual effects of rock mass fissure closure and interlocking joint expansion, a dynamic evolution model of the equivalent permeability coefficient of the contact surface is established. This model is embedded into the interface units, and during the fluid-structure interaction iteration of foundation pit excavation and dewatering, the permeability coefficient is updated in real time with changes in contact surface stress, yielding the stress and seepage field affected by construction disturbances. Based on the calculation results, the hydraulic gradient and structural uplift pressure are extracted to complete the cofferdam's seepage resistance safety assessment and optimize the embedded rock waterproofing design parameters. This provides reliable technical support for optimizing the design of cofferdam waterproofing structures.

Description

Technical Field

[0001] This invention belongs to the field of cofferdam seepage prevention technology, and more specifically, relates to a method and system for analyzing rock-embedded water-stopping in strongly weathered rock strata cofferdams based on numerical simulation. Background Technology

[0002] In the construction of water-related projects such as water conservancy hubs and municipal foundation pits along rivers, steel sheet pile cofferdams are the core temporary structures for isolating external water bodies and ensuring dry construction of the foundation pit. Strongly weathered rock strata are widely used as the commonly used embedded bearing layer in cofferdams. Due to the influence of geological weathering, the integrity and degree of fissure development of strongly weathered rock masses change continuously along the burial depth. There are obvious vertical gradient changes in the permeability and mechanical parameters of the strata. In addition, the rock mass is densely fissured and easily softens when exposed to water. Seepage control in the embedded rock section of the cofferdam has always been a key and difficult point in the project.

[0003] Currently, the design and stability analysis of cofferdams for water cutoff largely rely on traditional empirical formulas and homogenized numerical models, leading to various technical shortcomings. Conventional geological modeling generally ignores the weathering gradient distribution characteristics of rock strata and uses uniform values ​​for permeability and deformation parameters of rock masses at different depths, resulting in significant deviations between model geological conditions and actual field conditions. In numerical simulation calculations, the industry mostly uses a fixed contact surface permeability coefficient, which cannot reflect the disturbance effects brought about by sheet pile driving. The squeezing effect of pile driving will compact the original fissures in the surrounding rock mass, reducing the interface seepage capacity, while the eccentric force on the pile will cause the interlock to deform and open, increasing the seepage channels in the fissures. These two effects simultaneously change the interface permeability, and existing technologies cannot quantify the dynamic changes in the permeability coefficient caused by these two opposing effects.

[0004] Throughout the entire process of foundation pit excavation and dewatering, the seepage field and stress field are coupled and evolve together. The stress at the contact surface continuously changes and affects the seepage prevention effect. Traditional algorithms cannot dynamically update seepage parameters with stress changes, resulting in large errors in the calculated seepage distribution and structural uplift pressure data. During the engineering design phase, key water-stopping parameters such as the rock embedment depth and the spacing of steel sheet piles are mostly determined based on construction experience. Conservative parameter selection will significantly increase steel input and raise project costs, while underestimating these values ​​can easily induce safety accidents such as seepage around the rock embedment section, sudden heave in the foundation pit, and instability of the cofferdam.

[0005] Frequent leakage not only slows down construction progress but also easily leads to major safety hazards such as foundation pit collapse. The industry lacks systematic numerical analysis methods that can take into account the weathering characteristics of the strata and the effects of construction disturbance, which restricts the development of cofferdam water-stopping structure design. Therefore, new analytical methods are urgently needed to solve the above-mentioned engineering problems. Summary of the Invention

[0006] This invention aims to overcome the shortcomings of existing technologies that ignore the weathering gradient of rock strata, have fixed permeability coefficients, and are difficult to quantify the impact of pile driving disturbances. It establishes a dynamic evolution analysis system for contact surface permeability based on numerical simulation, restores the variation law of stress field and seepage field under construction disturbance, scientifically conducts anti-seepage stability calculation of cofferdams, optimizes key parameters of rock-embedded water stop, and takes into account both engineering safety and economy.

[0007] To address the aforementioned deficiencies or improvement needs of existing technologies, as a first aspect of this invention, the present invention provides a numerical simulation-based method for analyzing the rock-embedded water-stopping mechanism of cofferdams in strongly weathered rock strata, comprising: S1. Obtain exploration data of strongly weathered rock strata, construct a three-dimensional geological model containing weathering gradient characteristics, and set contact surface units at the interface between steel sheet piles and rock strata; S2. For the process of driving steel sheet piles into strongly weathered rock layers, calculate the distribution of compressive stress in the rock mass on the pile side and the deflection deformation of the steel sheet pile interlock. Based on the rock mass fissure closure effect caused by the compressive stress and the interlock gap expansion effect caused by the deflection deformation, construct a dynamic evolution model of the equivalent permeability coefficient of the pile-rock contact surface. S3. The equivalent permeability coefficient dynamic evolution model is embedded into the contact surface unit. In the fluid-structure interaction iterative calculation of the foundation pit excavation and dewatering process, the equivalent permeability coefficient is dynamically updated according to the time-varying data of the effective stress of the contact surface to obtain the seepage field and stress field distribution data considering the influence of construction disturbance. S4. Based on the seepage field and stress field distribution data, extract the local hydraulic gradient of the rock-embedded section and the uplift pressure of the water-stopping structure, and conduct anti-seepage stability evaluation and rock-embedded water-stopping parameter optimization.

[0008] Furthermore, the construction of a three-dimensional geological model including weathering gradient features in S1 specifically includes: The RQD index and P-wave velocity of the rock mass at different depths were obtained from the borehole core logging, and the rock mass integrity coefficient was determined by the ratio of the RQD index to the P-wave velocity of the intact rock mass. Based on the rock mass integrity coefficient, the strongly weathered rock layer is divided into several weathered sub-layers along the depth direction; For each weathered sublayer, a mapping relationship between the permeability coefficient and the rock mass integrity coefficient is established based on the water pressure test data. The permeability coefficient and deformation modulus of each weathered sublayer are assigned to the model unit of the corresponding layer to obtain a three-dimensional geological model containing weathering gradient characteristics.

[0009] Furthermore, the contact surface unit in S1 is specifically: A thin interface unit with a preset small thickness is set between the shell unit of the steel sheet pile and the solid unit of the strongly weathered rock layer. The thickness of the thin interface unit is determined according to the thickness of the rock mass disturbance zone around the pile caused by the construction of the steel sheet pile. The mechanical properties of the thin-layer interface unit are set as follows: the normal direction adopts a hard contact model that allows separation but not penetration to transfer the pile side compressive stress, and the tangential direction adopts an elastoplastic slip model based on the Coulomb friction criterion to transfer the pile rock shear stress. The interface shear strength parameter is determined according to the residual strength of the strongly weathered rock layer. The seepage properties of the thin-layer interface unit are set as follows: a pore water pressure degree of freedom is added at the unit node, and an initial normal permeability coefficient and an initial tangential permeability coefficient are assigned to match the initial fracture aperture of the strongly weathered rock layer; the normal permeability coefficient is used to characterize the transverse seepage of groundwater through the pile-rock interface under the action of the water head difference inside and outside the foundation pit, and the tangential permeability coefficient is used to characterize the longitudinal flow of groundwater around the surface of the steel sheet pile embedded rock section. The thin-layer interface unit is configured to receive dynamically updated equivalent permeability coefficients in fluid-structure interaction calculations to replace the initial normal permeability coefficient and the initial tangential permeability coefficient.

[0010] Furthermore, the calculation of the compressive stress distribution of the rock mass along the pile side in S2 specifically includes: The cross-section of the sheet pile is equivalent to a cylindrical hole based on its cross-sectional area, and the equivalent expansion radius is determined. The initial in-situ in-situ stress and static lateral pressure coefficient of the strongly weathered rock layer with depth are obtained as the initial boundary conditions for the hole expansion calculation. Based on the theory of circular hole expansion, the modified Mohr-Coulomb strength criterion, which considers the strain softening characteristics and shear dilatation angle of strongly weathered rock mass, is used as the plastic yield condition to calculate the radius of the plastic zone around the pile during pile penetration and the total radial stress distribution in the plastic zone, including excess pore water pressure. The dissipation ratio of excess pore water pressure is calculated based on the pile driving rate and the permeability coefficient of the strongly weathered rock mass. The undissipated excess pore water pressure is subtracted from the total radial stress to obtain the effective radial stress of the rock mass along the pile. The effective radial stress is used as the compressive stress of the rock mass along the pile to obtain the distribution function of the compressive stress as a function of depth and distance from the pile wall.

[0011] Furthermore, the calculation process for the deflection deformation of the sheet pile interlock in S2 specifically includes: The hammering energy and penetration depth during the pile driving process are obtained. Combined with the local end-face resistance distribution of the strongly weathered rock layer embedded section, the eccentric penetration resistance caused by rock surface inclination or local lithological differences is calculated, and the eccentric penetration resistance is converted into eccentric torque acting on the pile end and the interlocking node. The sheet pile body is equivalent to an elastic foundation beam, and the interlocking joint between adjacent sheet piles is equivalent to a nonlinear spring node with initial interlocking gap and local contact stiffness. A coupled deflection mechanical model including the overall deflection of the pile body and the local opening of the interlocking joint is established. Using the eccentric moment as the driving load input to the coupled deflection mechanical model, the relative deflection angle and axial relative displacement at the lock joint node are calculated; combined with the structural geometric parameters of the lock tenon and mortise groove, the lateral opening of the lock joint caused by the relative deflection angle and the longitudinal disengagement of the lock joint caused by the axial relative displacement are calculated, and the two are vector superimposed to obtain the lock joint gap width, which is used as the deflection deformation amount.

[0012] Furthermore, the dynamic evolution model of the equivalent permeability coefficient of the pile-rock contact surface constructed in S2 specifically includes: Using the effective compressive stress at the contact surface as the independent variable, and combining the initial fracture aperture and fracture normal closure stiffness of the strongly weathered rock mass, the dynamic fracture aperture is calculated; based on the cubic law, the dynamic fracture aperture is converted into the rock mass permeability coefficient, and the residual permeability coefficient of the strongly weathered rock block is set as the lower limit of attenuation to construct the first permeability evolution function characterizing the rock mass fracture closure effect. Using the width of the lock gap as the independent variable, a shape correction factor reflecting the tortuosity of the flow path inside the lock groove is introduced. Based on the parallel plate gap flow theory, a cubic nonlinear relationship between the gap width and the permeability coefficient is established, and a second permeation evolution function characterizing the expansion effect of the lock gap is constructed. Based on the equivalent thickness of the thin-layer interface unit, the rock mass water conductivity corresponding to the first permeability evolution function and the interlock water conductivity corresponding to the second permeability evolution function are superimposed according to the parallel seepage path, and then divided by the equivalent thickness for homogenization, to obtain a dynamic evolution model of the equivalent permeability coefficient of the pile-rock contact surface as a function of effective compressive stress and interlock gap width.

[0013] Furthermore, in step S3, the equivalent permeability coefficient is dynamically updated based on time-varying data of the effective stress at the contact surface, specifically including: During the iteration process within each incremental step of the fluid-structure interaction calculation, the effective normal stress at each integration point of the pile-rock contact surface element is extracted, and the relative normal displacement and relative tangential displacement of the contact surface element node are extracted to update the interlock gap width. The effective normal stress and the updated interlock gap width are substituted into the equivalent permeability coefficient dynamic evolution model to calculate the equivalent permeability coefficient corresponding to the current iteration step, and the permeability stiffness matrix of the pile-rock contact surface unit is updated accordingly. A comprehensive convergence criterion is established, which includes the relative change in permeability coefficient, the residual pore water pressure, and the nodal flow imbalance. When all of the comprehensive convergence criteria are less than their respective preset tolerance thresholds, the current incremental step is determined to be converged and the next incremental step is entered. Otherwise, the seepage field is resolved based on the updated permeability stiffness matrix to obtain a new pore water pressure distribution. The effective normal stress is updated in combination with the mechanical equilibrium equation. The stress-seepage-permeability coefficient alternating iterative correction is performed in the current incremental step until the comprehensive convergence criterion is met.

[0014] Furthermore, in step S4, the anti-seepage stability evaluation and rock-embedded water-stopping parameter optimization are carried out, specifically including: The local hydraulic gradient of the embedded rock section is compared with the allowable hydraulic gradient of the strongly weathered rock mass layer by layer to identify dangerous layers where the hydraulic gradient exceeds the limit. The uplift pressure of the water-stopping structure is compared with the sum of the structure's self-weight and side friction resistance to calculate the anti-buoyancy stability safety factor. Using the rock embedment depth and sheet pile spacing as optimization variables, the hydraulic gradient of the dangerous stratum being reduced to within the allowable value and the anti-buoyancy stability safety factor meeting the preset requirements as constraints, and the minimum total steel consumption as the objective function, the rock embedment water-stopping parameters are optimized.

[0015] As a second aspect of the present invention, a numerical simulation-based analysis system for rock-embedded water-stopping cofferdams in strongly weathered rock strata is also provided, comprising: The three-dimensional geological model construction unit is used to acquire exploration data of strongly weathered rock layers to construct a three-dimensional geological model containing weathering gradient characteristics, and to set contact surface units at the interface between the steel sheet pile and the rock layer. The permeability evolution model construction unit is used to calculate the distribution of compressive stress in the rock mass on the pile side and the deflection deformation of the steel sheet pile interlock during the process of driving steel sheet piles into strongly weathered rock layers. Based on the rock mass fracture closure effect caused by the compressive stress and the interlock gap expansion effect caused by the deflection deformation, an equivalent permeability coefficient dynamic evolution model of the pile-rock contact surface is constructed. The fluid-structure interaction iterative calculation unit is used to embed the dynamic evolution model of the equivalent permeability coefficient into the contact surface unit. In the fluid-structure interaction iterative calculation of the foundation pit excavation and dewatering process, the equivalent permeability coefficient is dynamically updated according to the time-varying data of the effective stress of the contact surface, and the seepage field and stress field distribution data considering the influence of construction disturbance are obtained. The anti-seepage evaluation and parameter optimization unit is used to extract the local hydraulic gradient and uplift pressure of the rock-embedded section based on the seepage field and stress field distribution data, and to evaluate the anti-seepage stability and optimize the rock-embedded water-stopping parameters.

[0016] As a third aspect of the present invention, a computer-readable storage medium is also provided, having a computer program stored thereon, the computer program being executed by a processor of any of the methods described above for analyzing the rock-embedded water-stopping method of cofferdams in strongly weathered rock strata based on numerical simulation.

[0017] In summary, compared with the prior art, the above-described technical solutions conceived by this invention can achieve the following beneficial effects: 1. The present invention provides a numerical simulation-based method for analyzing the embedded rock-stopping of cofferdams in strongly weathered rock strata. This method divides the weathered sub-layers using rock integrity coefficients and assigns stratigraphic parameters based on pressure water tests, constructing a three-dimensional geological model with weathering gradient characteristics. Simultaneously, thin contact surface units are arranged at the contact points between the sheet piles and the rock strata. This approach completes vertical strata ...

[0018] 2. The present invention provides a numerical simulation-based method for analyzing the embedded rock water-stopping of cofferdams in strongly weathered rock strata. This method calculates the pile-side compressive stress using the circular hole expansion theory, determines the interlocking deformation using an elastic foundation beam model, and establishes a dynamic evolution model of the equivalent permeability coefficient by combining the effects of fissure closure and interlocking expansion. The radial compressive stress generated by pile driving is calculated using a modified strength criterion, and the interlocking gap size is converted using eccentric penetration resistance. Two evolution functions are constructed: one for rock mass compaction reducing permeability, and the other for fissure opening increasing permeability. Finally, the parameters are integrated according to parallel seepage paths to obtain the equivalent permeability coefficient. This calculation path objectively reflects the two opposing seepage changes brought about by pile driving, overcoming the limitations of previous numerical simulations that used a constant permeability coefficient. It achieves a quantitative description of the permeability performance of the pile-rock interface as a function of stress and deformation, quantifies the comprehensive impact of construction disturbance on the interface's permeability, and improves the quantitative calculation basis for seepage changes at the contact surface.

[0019] 3. The numerical simulation-based method for embedded rock-stopping cofferdams in strongly weathered rock strata of this invention embeds an equivalent permeability coefficient evolution model into pre-set contact surface units. During the fluid-structure interaction iteration of foundation pit excavation and dewatering, permeability parameters are updated in real time. Stability testing and optimization of water-stopping parameters are completed based on the stress-seepage data obtained from the solution. In each iteration, the effective stress of the contact surface and nodal displacement are extracted to dynamically correct the permeability coefficient. Multiple convergence criteria are used to control the accuracy of iterative calculations. After solving the global seepage field and stress field, anti-seepage and anti-buoyancy calculations are performed by comparing the hydraulic gradient and structural uplift pressure. The embedded rock depth and pile spacing are optimized with the goal of minimizing steel consumption. The entire computational process achieves dynamic simulation of seepage and stress changes in conjunction with construction conditions, improving the reliability of the simulation results, identifying weak seepage layers, optimizing engineering materials while meeting structural safety specifications, and balancing the safety and economy of cofferdam construction. Attached Figure Description

[0020] Figure 1 This is a flowchart of an analysis method for rock-embedded water-stopping cofferdams based on numerical simulation in an embodiment of the present invention. Figure 2 This is a schematic diagram of the construction site of a steel sheet pile cofferdam for a water-related engineering project according to an embodiment of the present invention; Figure 3 This is a schematic diagram comparing the distribution of permeability coefficients along depth according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the steel sheet pile penetration construction according to an embodiment of the present invention; Figure 5 This is a schematic diagram of the system units in an embodiment of the present invention. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0022] Example 1 Please refer to Figure 1 This embodiment 1 provides a numerical simulation-based method for analyzing the rock-embedded water-stopping analysis of cofferdams in strongly weathered rock strata, including: S1. Obtain exploration data of strongly weathered rock strata, construct a three-dimensional geological model containing weathering gradient characteristics, and set contact surface units at the interface between steel sheet piles and rock strata; S2. For the process of driving steel sheet piles into strongly weathered rock layers, calculate the distribution of compressive stress in the rock mass on the pile side and the deflection deformation of the steel sheet pile interlock. Based on the rock mass fissure closure effect caused by the compressive stress and the interlock gap expansion effect caused by the deflection deformation, construct a dynamic evolution model of the equivalent permeability coefficient of the pile-rock contact surface. S3. The equivalent permeability coefficient dynamic evolution model is embedded into the contact surface unit. In the fluid-structure interaction iterative calculation of the foundation pit excavation and dewatering process, the equivalent permeability coefficient is dynamically updated according to the time-varying data of the effective stress of the contact surface to obtain the seepage field and stress field distribution data considering the influence of construction disturbance. S4. Based on the seepage field and stress field distribution data, extract the local hydraulic gradient of the rock-embedded section and the uplift pressure of the water-stopping structure, and conduct anti-seepage stability evaluation and rock-embedded water-stopping parameter optimization.

[0023] Please refer to Figure 2 This embodiment 1 further elaborates on the above steps.

[0024] (1) Construction of three-dimensional geological model Due to weathering, the integrity and physical and mechanical parameters of strongly weathered rock strata continuously change with burial depth. Traditional modeling often simplifies the entire stratum as a homogeneous structure, uniformly assigning mechanical and seepage parameters. This results in geological models that deviate significantly from actual geological conditions, hindering subsequent cofferdam seepage calculations. Therefore, it is necessary to first obtain survey data of strongly weathered rock strata and construct a three-dimensional geological model incorporating weathering gradient characteristics. The specific process for constructing the three-dimensional geological model is as follows: Please refer to Figure 3 First, detailed exploration data, especially borehole core logging data, was obtained within the project area. For strongly weathered rock strata, a data sample was collected every 0.5 meters along the depth direction to measure the rock mass RQD index and P-wave velocity at that depth. Then, the rock mass integrity coefficient was calculated. Its calculation formula is ,in To measure the longitudinal wave velocity of the rock mass, The longitudinal wave velocity is the velocity of the intact rock block. Subsequently, the calculated... Using a threshold value as the basis for stratification, the strongly weathered rock layer is divided into multiple weathered sub-layers along the depth direction, including upper, middle, and lower strongly weathered layers, ensuring that the physical and mechanical properties of the rock mass within each sub-layer are relatively uniform. Next, for each divided weathered sub-layer, the permeability coefficient is established based on field pressure water test data. With rock mass integrity coefficient Mapping function relation Finally, in the 3D modeling software, the permeability coefficient and deformation modulus parameters corresponding to each weathered sublayer are assigned to the solid elements of the corresponding layer in the model, thereby constructing a 3D geological model that can reflect the heterogeneous characteristics of the rock mass as it changes with depth.

[0025] Please refer to Figure 4 After constructing the 3D geological model, the contact surface elements are set. First, a thin interface element with a preset small thickness is set between the shell element of the sheet pile and the solid element of the strongly weathered rock layer. The thickness of this thin interface element... It is not a fixed value, but rather depends on the sheet pile construction process and hammering energy, combined with empirical formulas. Confirmed, among which For the pile diameter, The disturbance coefficient is used. In terms of mechanical property definition, the normal direction of the thin-layer unit adopts the "hard contact" model, which allows the contact surface to separate under tension but does not allow penetration under compression, so as to accurately transmit the compressive stress of the rock mass on the pile side; the tangential direction adopts the elasto-plastic slip model based on the Coulomb friction criterion. The interface shear strength parameters (including cohesion and internal friction angle) are determined by reducing the residual strength index of the strongly weathered rock layer. The reduction coefficient is selected based on the results of the field direct shear test to simulate the slip characteristics of the rock mass structural surface.

[0026] Then, pore water pressure degrees of freedom are added at the nodes of the thin-layer interface elements to enable them to calculate fluid flow. Based on the initial fracture aperture of the strongly weathered rock layer, the cubic law is used to calculate and assign an initial normal permeability coefficient to the contact surface elements. and initial tangential permeability coefficient Among them, the normal permeability coefficient Used to characterize the lateral seepage capacity of groundwater vertically through the pile-rock interface under the action of water head difference inside and outside the foundation pit; tangential permeability coefficient This is used to characterize the ability of groundwater to flow longitudinally around the surface of the sheet pile embedded in rock. Simultaneously, configuring this thin-layer interface element allows it to receive and update the equivalent permeability coefficient in subsequent fluid-structure interaction calculations, enabling it to dynamically replace the initial permeability coefficient based on the real-time calculated stress state, thereby achieving the transformation from a static geometric model to a dynamic physical model.

[0027] (2) Construction of the penetration evolution model For the process of driving sheet piles into strongly weathered rock strata, the distribution of compressive stress in the rock mass along the pile side and the deflection deformation of the sheet pile interlock are first calculated. Then, based on the rock mass fracture closure effect caused by compressive stress and the interlock gap expansion effect caused by the deflection deformation, a dynamic evolution model of the equivalent permeability coefficient of the pile-rock contact surface is constructed. The specific process of constructing the dynamic evolution model of the equivalent permeability coefficient of the pile-rock contact surface is as follows: First, the distribution of compressive stress in the rock mass along the pile is calculated. The cross-section of the sheet pile is equivalent to a cylindrical hole in terms of cross-sectional area, and the equivalent expansion radius equation is used. Determine the equivalent expansion radius ,in This represents the cross-sectional area of ​​a single sheet pile. The method for obtaining the cross-sectional area of ​​strongly weathered rock strata varies with depth. The changing initial in-situ stress is expressed as the initial effective radial stress. , as the initial boundary condition for the hole expansion calculation, where This is the coefficient of lateral pressure at rest. The effective unit weight of the rock mass. Based on the theory of circular hole expansion, the strain softening characteristics and dilatation angle of strongly weathered rock mass are considered. The modified Mohr-Coulomb strength criterion is used as a plastic yield condition, which introduces the residual cohesion of the rock mass. and residual internal friction angle Calculate the radius of the plastic zone around the pile during pile driving. It satisfies the equation ,in The ultimate expansion pressure of the pore wall is given. Then, the total radial stress distribution within the plastic zone, including excess pore water pressure, is determined. ,in This is the radial distance from the center of the pile. Then, based on the pile driving rate... Permeability coefficient of strongly weathered rock mass Calculate the dissipation ratio of excess pore water pressure ,in The consolidation coefficient factor is related to the drainage path. The effective radial stress equation of the pile-side rock mass is obtained by subtracting the undissipated excess pore water pressure from the total radial stress distribution. ,in The initial excess pore water pressure generated during pile driving. Effective radial stress. As the compressive stress of the rock mass along the pile, the distribution function of the compressive stress as a function of depth and distance from the pile wall is obtained.

[0028] Secondly, the deflection deformation of the sheet pile interlock is calculated. The hammer energy during pile driving is obtained. With penetration Combined with the local end-face resistance distribution of the strongly weathered rock layer embedded section Calculate the eccentric penetration resistance caused by rock surface inclination or local lithological differences. And through the eccentric moment equation This is converted into an eccentric moment acting on the pile tip and the interlocking joint. ,in Let be the eccentricity of the point of resultant force of end-face resistance from the centroid of the pile. The sheet pile is treated as an elastic foundation beam, and the bending stiffness of the pile is introduced. Lateral restraint stiffness of the rock strata embedded in the pile shaft Simultaneously, the interlocking joints between adjacent pile plates are equivalent to having an initial interlocking gap. and local contact stiffness A coupled deflection mechanics model is established for the nonlinear spring node, incorporating both overall pile deflection and local opening of the interlock. The governing differential equation of this model is: ,in For the pile body along the depth direction Flexural displacement. For the Dirac function, This refers to the depth of the pile tip embedded in the rock. The eccentric moment is used. To drive the load input into the model, the relative deflection angle at the lock node is solved. relative displacement with respect to the axial direction Based on the structural geometric parameters of the male and female tenons of the lock, the lateral opening of the lock caused by the relative deflection angle is calculated. (in (This refers to the effective contact length of the tenon and groove), and the longitudinal disengagement of the lock joint caused by axial relative displacement. (in (This represents the initial overlap depth). By vector superposition of the two, the equation for the lock gap width is obtained. This is used as the final deflection deformation quantity.

[0029] Finally, a dynamic evolution model of the equivalent permeability coefficient at the pile-rock contact surface is constructed. This model is based on the effective compressive stress at the contact surface. As the independent variable, combined with the initial fracture aperture of the strongly weathered rock mass With the normal closing stiffness of the crack Calculate dynamic fracture aperture Based on the cubic law, the dynamic fracture aperture is converted into the rock mass permeability coefficient, and the residual permeability coefficient of the strongly weathered rock block is set. As the lower limit of attenuation, a first permeability evolution function characterizing the rock mass fracture closure effect is constructed. ,in For fluid density, It is the acceleration due to gravity. Let be the hydrodynamic viscosity coefficient. The width of the lock gap is used as the metric. A shape correction factor is introduced as the independent variable to reflect the tortuosity of the flow path inside the lock tenon groove. Based on the parallel plate slot flow theory, a cubic nonlinear relationship between slot width and permeability coefficient is established, and a second permeability evolution function characterizing the slot expansion effect is constructed. Based on the equivalent thickness of the thin-layer interface unit The rock mass hydraulic conductivity corresponding to the first permeability evolution function and the interlock hydraulic conductivity corresponding to the second permeability evolution function are superimposed according to the parallel seepage path, and then divided by the equivalent thickness for homogenization. Finally, the dynamic evolution equation of the equivalent permeability coefficient of the pile-rock contact surface is obtained. ,in The equivalent thickness for seepage through rock fractures. The equivalent thickness for seepage through the lock gap, and satisfying the following conditions. This model achieves an equivalent permeability coefficient. Dynamic quantitative characterization of changes in effective compressive stress and lock gap width.

[0030] (3) Fluid-structure interaction iterative calculation After completing the construction of the dynamic evolution model of the equivalent permeability coefficient of the pile-rock contact surface and the thin-layer contact surface unit, the dynamic evolution model of the equivalent permeability coefficient is embedded into the thin-layer contact surface unit. Simultaneously, fluid-structure interaction iterative calculations are performed for the foundation pit excavation and dewatering process. The equivalent permeability coefficient is dynamically updated based on the time-varying data of the effective stress at the contact surface, and the seepage field and stress field distribution data considering the influence of construction disturbance are obtained. The specific calculation process of the fluid-structure interaction iterative calculation is as follows: First, in the current incremental step of the fluid-structure interaction calculation... During each iteration, the state variables of the contact surface are extracted and updated. The pile-rock contact surface elements are traversed, and each integration point is extracted. Effective normal stress at the location Simultaneously, extract each node of the contact surface unit. Relative normal displacement at point With relative tangential displacement Based on the extracted nodal displacements, the equation is updated using the gap width. Calculate the gap width at each node in the current iteration step. Subsequently, the width of the lock gap at the node is determined using a unit shape function. Interpolation mapping to integration points At the point of integration, obtain the width of the lock gap. This allows for real-time updates of the lock gap width.

[0031] Secondly, the equivalent permeability coefficient is calculated and the permeability stiffness matrix is ​​updated. The effective normal stress at the integration point is then calculated. With the updated lock gap width Substitute them together into the aforementioned dynamic evolution model of equivalent permeability coefficient In the process, calculate the equivalent penetration coefficient corresponding to each integration point in the current iteration step. Based on the calculated equivalent permeability coefficient The permeability stiffness matrix of the pile-rock contact element is assembled and updated using the Gaussian integral method. Its integral expression is ,in The seepage gradient matrix is... The permeability constitutive matrix depends on the equivalent permeability coefficient. Let be the volume domain of the contact surface element.

[0032] Next, a comprehensive convergence criterion is established and evaluated. The relative change in permeability coefficient is calculated. ,in To prevent extremely small positive constants with a denominator of zero, The equivalent permeability coefficient of the previous iteration; calculate the pore water pressure residual norm. ,in Given the pore water pressure imbalance force vector for the current iteration step; calculate the nodal flow imbalance. ,in and These are the inflow and outflow vectors of the contact surface unit in the current iteration step, respectively. The above three indicators are then compared with a preset permeability coefficient tolerance threshold. Pore ​​water pressure tolerance threshold and flow tolerance threshold Compare them.

[0033] Finally, the subsequent calculation process is executed based on the evaluation results of the comprehensive convergence criterion. When the convergence criterion is satisfied... , and If convergence is achieved, the current increment step is determined to have converged, the iteration ends, and the next increment step begins; otherwise, the current increment step is determined to have not converged, and the iteration proceeds based on the updated penetration stiffness matrix. Resolve the seepage control equations To obtain a new pore water pressure distribution vector ,in Let be the external flow boundary load vector. Then, combining the mechanical equilibrium equations, the new pore water pressure distribution is transformed into effective stress, and the effective normal stress is updated. Within the current increment step, perform alternating iterative corrections of stress, seepage, and permeability coefficient until the above comprehensive convergence criterion is met.

[0034] Once the current increment step is deemed convergent according to the comprehensive convergence criterion, the final extraction and synthesis of seepage field and stress field distribution data, taking into account the impact of construction disturbance, is performed. First, for the stress field distribution data, the global node displacement vector after convergence in the current increment step is extracted. Combined with the rock mass shear modulus reduction coefficient caused by high-frequency vibration during pile driving Update the rock mass elastoplastic constitutive matrix and incorporate the equivalent nodal release force vector generated by the excavation unloading. Through the stress recovery equation Calculate the total stress tensor at each element integration point. ,in For the elastoplastic stiffness matrix that takes into account vibration reduction effects, The strain-displacement matrix, Let be the initial geostress tensor. To release the force vector from the equivalent node The transformed excavation unloading stress increment tensor; Subsequently, the global node pore water pressure vector after the current incremental step converges is extracted. Through the effective stress principle equation Calculate the global effective stress tensor ,in For Biot coefficient, The pore water pressure shape function matrix, As a unit tensor, the effective stress tensor over the entire domain With total stress tensor Together, they form the final stress field distribution data.

[0035] Secondly, for the seepage field distribution data, based on the converged global nodal pore water pressure vector... The distribution vector of the initial excess pore water pressure field generated by the superposition of pile driving and soil squeezing effects. Obtain the true pore water pressure distribution vector considering construction disturbance. Simultaneously, an amplification factor for the permeability coefficient disturbance caused by rock mass fracture propagation due to pile driving vibration is introduced. Combining the converged equivalent permeability coefficient matrix, and applying Darcy's law equation... Calculate the global seepage velocity vector ,in The final equivalent permeability coefficient after convergence. This is the corresponding final permeability constitutive matrix. The seepage gradient matrix is ​​used; the actual pore water pressure distribution vector is used. With the global seepage velocity vector Together, they form the final seepage field distribution data, thus completing the quantitative acquisition of fluid-structure interaction field distribution data that takes into account the impact of construction disturbance.

[0036] (4) Permeability evaluation and parameter optimization After completing the fluid-structure interaction calculation, the local hydraulic gradient of the rock-embedded section and the uplift pressure of the water-stopping structure are extracted based on the seepage field and stress field distribution data, and the anti-seepage stability evaluation and rock-embedded water-stopping parameters are optimized.

[0037] First, the local hydraulic gradient of the embedded rock section is extracted and its seepage stability is evaluated. After the numerical simulation converges, the post-processing module is used to traverse all contact surface units and adjacent rock mass units of the sheet pile embedded rock section. For each weathered sub-layer, the hydraulic head difference along the groundwater seepage path within that layer is extracted. With seepage path length The actual local hydraulic gradient of this layer was calculated. The calculation formula is: Simultaneously, based on the lithological characteristics and particle size distribution curves of each weathered sublayer, its allowable hydraulic gradient was determined. The calculated actual local hydraulic gradients at each stratum are then used to... With the corresponding allowable hydraulic gradient Perform a layer-by-layer comparison. If a certain layer satisfies... If the hydraulic gradient exceeds the limit, the layer is determined to be a dangerous layer with a risk of seepage failure and should be the focus of subsequent optimization.

[0038] Secondly, the uplift pressure of the water-stopping structure was extracted and its anti-buoyancy stability was evaluated. Data on the pore water pressure distribution on the water-facing and backwater surfaces of the sheet pile embedded section were extracted. The normal water pressure on the sheet pile surface was integrated to calculate the total uplift pressure acting on the water-stopping structure. At the same time, the weight of the sheet pile itself is calculated. and the ultimate side friction provided by the soil and rock mass along the pile. Side friction resistance The calculation needs to consider the effective stress principle, that is ,in and These represent the effective cohesion and effective internal friction angle at the pile-rock interface, respectively. For the effective stress in the interface normal direction, Let be the contact area. Based on the above parameters, calculate the anti-buoyancy stability safety factor. The formula is as follows: The calculated anti-buoyancy stability safety factor Compared with the preset safety threshold required by the standard Perform a comparison. If... This indicates that the waterstop structure is at risk of floating and becoming unstable under the current working conditions, and the design parameters need to be adjusted.

[0039] Finally, multi-objective optimization of the rock-embedded water-stopping parameters was performed. A parameter based on the rock-embedded depth was established. Spacing between sheet piles This is an optimization model for decision variables. The constraint is set as: the actual local hydraulic gradient of all weathered sublayers. All are less than or equal to the allowable hydraulic gradient And the anti-buoyancy stability safety factor Greater than or equal to the preset threshold Construct based on total steel consumption Minimize the total steel consumption as the objective function; the total steel consumption can be expressed as: ,in For the density of steel, This is the cross-sectional area of ​​a single pile. For the height of the wall above ground, Let the perimeter of the cofferdam be denoted as . Intelligent optimization algorithms, such as genetic algorithms or particle swarm optimization, are used to search for the optimal rock-embedded depth within the solution space that satisfies the constraints. Spacing between sheet piles Through iterative calculations, the geometric parameters in the numerical model are continuously corrected and the fluid-structure interaction analysis is rerun until the optimal design scheme is found that can eliminate the seepage risk of dangerous layers, ensure anti-buoyancy safety, and minimize the project cost, thus completing the design of the cofferdam embedded rock water-stopping system for strongly weathered rock strata.

[0040] Example 2 Please refer to Figure 5 This embodiment 2 provides a numerical simulation-based analysis system for rock-embedded water-stopping cofferdams in strongly weathered rock strata, comprising: The three-dimensional geological model construction unit is used to acquire exploration data of strongly weathered rock layers to construct a three-dimensional geological model containing weathering gradient characteristics, and to set contact surface units at the interface between the steel sheet pile and the rock layer. The permeability evolution model construction unit is used to calculate the distribution of compressive stress in the rock mass on the pile side and the deflection deformation of the steel sheet pile interlock during the process of driving steel sheet piles into strongly weathered rock layers. Based on the rock mass fracture closure effect caused by the compressive stress and the interlock gap expansion effect caused by the deflection deformation, an equivalent permeability coefficient dynamic evolution model of the pile-rock contact surface is constructed. The fluid-structure interaction iterative calculation unit is used to embed the dynamic evolution model of the equivalent permeability coefficient into the contact surface unit. In the fluid-structure interaction iterative calculation of the foundation pit excavation and dewatering process, the equivalent permeability coefficient is dynamically updated according to the time-varying data of the effective stress of the contact surface, and the seepage field and stress field distribution data considering the influence of construction disturbance are obtained. The anti-seepage evaluation and parameter optimization unit is used to extract the local hydraulic gradient and uplift pressure of the rock-embedded section based on the seepage field and stress field distribution data, and to evaluate the anti-seepage stability and optimize the rock-embedded water-stopping parameters.

[0041] Example 3 This embodiment 3 also provides a computer-readable storage medium storing a computer program. When the computer program is executed by a processor, it can implement any step of a numerical simulation-based method for analyzing the rock-embedded water-stopping of a cofferdam in strongly weathered rock strata.

[0042] The computer-readable storage medium may include various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0043] For a description of the computer-readable storage medium provided in this application, please refer to the above method embodiments; further details will not be repeated here.

[0044] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A numerical simulation-based method for analyzing the rock-embedded water-stopping effect of cofferdams in strongly weathered rock strata, characterized in that, include: S1. Obtain exploration data of strongly weathered rock strata, construct a three-dimensional geological model containing weathering gradient characteristics, and set contact surface units at the interface between steel sheet piles and rock strata; S2. For the process of driving steel sheet piles into strongly weathered rock layers, calculate the distribution of compressive stress in the rock mass on the pile side and the deflection deformation of the steel sheet pile interlock. Based on the rock mass fissure closure effect caused by the compressive stress and the interlock gap expansion effect caused by the deflection deformation, construct a dynamic evolution model of the equivalent permeability coefficient of the pile-rock contact surface. S3. The equivalent permeability coefficient dynamic evolution model is embedded into the contact surface unit. In the fluid-structure interaction iterative calculation of the foundation pit excavation and dewatering process, the equivalent permeability coefficient is dynamically updated according to the time-varying data of the effective stress of the contact surface to obtain the seepage field and stress field distribution data considering the influence of construction disturbance. S4. Based on the seepage field and stress field distribution data, extract the local hydraulic gradient of the rock-embedded section and the uplift pressure of the water-stopping structure, and conduct anti-seepage stability evaluation and rock-embedded water-stopping parameter optimization.

2. The method for analyzing rock-embedded water-stopping in cofferdams based on numerical simulation according to claim 1, characterized in that, The construction of a three-dimensional geological model in S1, which includes weathering gradient features, specifically includes: The RQD index and P-wave velocity of the rock mass at different depths were obtained from the borehole core logging, and the rock mass integrity coefficient was determined by the ratio of the RQD index to the P-wave velocity of the intact rock mass. Based on the rock mass integrity coefficient, the strongly weathered rock layer is divided into several weathered sub-layers along the depth direction; For each weathered sublayer, a mapping relationship between the permeability coefficient and the rock mass integrity coefficient is established based on the water pressure test data. The permeability coefficient and deformation modulus of each weathered sublayer are assigned to the model unit of the corresponding layer to obtain a three-dimensional geological model containing weathering gradient characteristics.

3. The method for analyzing rock-embedded water-stopping in cofferdams based on numerical simulation according to claim 1, characterized in that, The contact surface unit in S1 is specifically: A thin interface unit with a preset small thickness is set between the shell unit of the steel sheet pile and the solid unit of the strongly weathered rock layer. The thickness of the thin interface unit is determined according to the thickness of the rock mass disturbance zone around the pile caused by the construction of the steel sheet pile. The mechanical properties of the thin-layer interface unit are set as follows: the normal direction adopts a hard contact model that allows separation but not penetration to transfer the pile side compressive stress, and the tangential direction adopts an elastoplastic slip model based on the Coulomb friction criterion to transfer the pile rock shear stress. The interface shear strength parameter is determined according to the residual strength of the strongly weathered rock layer. The seepage properties of the thin-layer interface unit are set as follows: a pore water pressure degree of freedom is added at the unit node, and an initial normal permeability coefficient and an initial tangential permeability coefficient are assigned to match the initial fracture aperture of the strongly weathered rock layer; the normal permeability coefficient is used to characterize the transverse seepage of groundwater through the pile-rock interface under the action of the water head difference inside and outside the foundation pit, and the tangential permeability coefficient is used to characterize the longitudinal flow of groundwater around the surface of the steel sheet pile embedded rock section. The thin-layer interface unit is configured to receive dynamically updated equivalent permeability coefficients in fluid-structure interaction calculations to replace the initial normal permeability coefficient and the initial tangential permeability coefficient.

4. The method for analyzing rock-embedded water-stopping in cofferdams based on numerical simulation according to claim 1, characterized in that, The calculation of the compressive stress distribution of the rock mass along the pile side in S2 specifically includes: The cross-section of the sheet pile is equivalent to a cylindrical hole based on its cross-sectional area, and the equivalent expansion radius is determined. The initial in-situ in-situ stress and static lateral pressure coefficient of the strongly weathered rock layer with depth are obtained as the initial boundary conditions for the hole expansion calculation. Based on the theory of circular hole expansion, the modified Mohr-Coulomb strength criterion, which considers the strain softening characteristics and shear dilatation angle of strongly weathered rock mass, is used as the plastic yield condition to calculate the radius of the plastic zone around the pile during pile penetration and the total radial stress distribution in the plastic zone, including excess pore water pressure. The dissipation ratio of excess pore water pressure is calculated based on the pile driving rate and the permeability coefficient of the strongly weathered rock mass. The undissipated excess pore water pressure is subtracted from the total radial stress to obtain the effective radial stress of the rock mass along the pile. The effective radial stress is used as the compressive stress of the rock mass along the pile to obtain the distribution function of the compressive stress as a function of depth and distance from the pile wall.

5. The method for analyzing rock-embedded water-stopping in cofferdams based on numerical simulation according to claim 1, characterized in that, The calculation process for the deflection deformation of the steel sheet pile interlock in S2 specifically includes: The hammering energy and penetration depth during the pile driving process are obtained. Combined with the local end-face resistance distribution of the strongly weathered rock layer embedded section, the eccentric penetration resistance caused by rock surface inclination or local lithological differences is calculated, and the eccentric penetration resistance is converted into eccentric torque acting on the pile end and the interlocking node. The sheet pile body is equivalent to an elastic foundation beam, and the interlocking joint between adjacent sheet piles is equivalent to a nonlinear spring node with initial interlocking gap and local contact stiffness. A coupled deflection mechanical model including the overall deflection of the pile body and the local opening of the interlocking joint is established. Using the eccentric moment as the driving load input to the coupled deflection mechanical model, the relative deflection angle and axial relative displacement at the lock joint node are calculated; combined with the structural geometric parameters of the lock tenon and mortise groove, the lateral opening of the lock joint caused by the relative deflection angle and the longitudinal disengagement of the lock joint caused by the axial relative displacement are calculated, and the two are vector superimposed to obtain the lock joint gap width, which is used as the deflection deformation amount.

6. The method for analyzing rock-embedded water-stopping in cofferdams based on numerical simulation according to claim 1, characterized in that, The dynamic evolution model of the equivalent permeability coefficient of the pile-rock contact surface constructed in S2 specifically includes: Using the effective compressive stress at the contact surface as the independent variable, and combining the initial fracture aperture and fracture normal closure stiffness of the strongly weathered rock mass, the dynamic fracture aperture is calculated; based on the cubic law, the dynamic fracture aperture is converted into the rock mass permeability coefficient, and the residual permeability coefficient of the strongly weathered rock block is set as the lower limit of attenuation to construct the first permeability evolution function characterizing the rock mass fracture closure effect. Using the width of the lock gap as the independent variable, a shape correction factor reflecting the tortuosity of the flow path inside the lock groove is introduced. Based on the parallel plate gap flow theory, a cubic nonlinear relationship between the gap width and the permeability coefficient is established, and a second permeation evolution function characterizing the expansion effect of the lock gap is constructed. Based on the equivalent thickness of the thin-layer interface unit, the rock mass water conductivity corresponding to the first permeability evolution function and the interlock water conductivity corresponding to the second permeability evolution function are superimposed according to the parallel seepage path, and then divided by the equivalent thickness for homogenization, to obtain a dynamic evolution model of the equivalent permeability coefficient of the pile-rock contact surface as a function of effective compressive stress and interlock gap width.

7. The method for analyzing rock-embedded water-stopping in cofferdams based on numerical simulation according to claim 1, characterized in that, The equivalent permeability coefficient in step S3 is dynamically updated based on time-varying data of the effective stress at the contact surface, specifically including: During the iteration process within each incremental step of the fluid-structure interaction calculation, the effective normal stress at each integration point of the pile-rock contact surface element is extracted, and the relative normal displacement and relative tangential displacement of the contact surface element node are extracted to update the interlock gap width. The effective normal stress and the updated interlock gap width are substituted into the equivalent permeability coefficient dynamic evolution model to calculate the equivalent permeability coefficient corresponding to the current iteration step, and the permeability stiffness matrix of the pile-rock contact surface unit is updated accordingly. A comprehensive convergence criterion is established, which includes the relative change in permeability coefficient, the residual pore water pressure, and the nodal flow imbalance. When all of the comprehensive convergence criteria are less than their respective preset tolerance thresholds, the current incremental step is determined to be converged and the next incremental step is entered. Otherwise, the seepage field is resolved based on the updated permeability stiffness matrix to obtain a new pore water pressure distribution. The effective normal stress is updated in combination with the mechanical equilibrium equation. The stress-seepage-permeability coefficient alternating iterative correction is performed in the current incremental step until the comprehensive convergence criterion is met.

8. The method for analyzing rock-embedded water-stopping in cofferdams based on numerical simulation according to claim 1, characterized in that, The S4 section includes an evaluation of impermeability stability and optimization of rock-embedded water-stopping parameters, specifically: The local hydraulic gradient of the embedded rock section is compared with the allowable hydraulic gradient of the strongly weathered rock mass layer by layer to identify dangerous layers where the hydraulic gradient exceeds the limit. The uplift pressure of the water-stopping structure is compared with the sum of the structure's self-weight and side friction resistance to calculate the anti-buoyancy stability safety factor. Using the rock embedment depth and sheet pile spacing as optimization variables, the hydraulic gradient of the dangerous stratum being reduced to within the allowable value and the anti-buoyancy stability safety factor meeting the preset requirements as constraints, and the minimum total steel consumption as the objective function, the rock embedment water-stopping parameters are optimized.

9. A numerical simulation-based analysis system for embedded rock water-stopping cofferdams in strongly weathered rock strata, characterized in that, include: The three-dimensional geological model construction unit is used to acquire exploration data of strongly weathered rock layers to construct a three-dimensional geological model containing weathering gradient characteristics, and to set contact surface units at the interface between the steel sheet pile and the rock layer. The permeability evolution model construction unit is used to calculate the distribution of compressive stress in the rock mass on the pile side and the deflection deformation of the steel sheet pile interlock during the process of driving steel sheet piles into strongly weathered rock layers. Based on the rock mass fracture closure effect caused by the compressive stress and the interlock gap expansion effect caused by the deflection deformation, an equivalent permeability coefficient dynamic evolution model of the pile-rock contact surface is constructed. The fluid-structure interaction iterative calculation unit is used to embed the dynamic evolution model of the equivalent permeability coefficient into the contact surface unit. In the fluid-structure interaction iterative calculation of the foundation pit excavation and dewatering process, the equivalent permeability coefficient is dynamically updated according to the time-varying data of the effective stress of the contact surface, and the seepage field and stress field distribution data considering the influence of construction disturbance are obtained. The anti-seepage evaluation and parameter optimization unit is used to extract the local hydraulic gradient and uplift pressure of the rock-embedded section based on the seepage field and stress field distribution data, and to evaluate the anti-seepage stability and optimize the rock-embedded water-stopping parameters.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, The computer program is executed by a processor according to any one of claims 1-8, which describes a numerical simulation-based method for analyzing the rock-embedded water-stopping of cofferdams in strongly weathered rock strata.

Images