Calculation method and system of lateral earth pressure adjacent to foundation pit under the action of tunnel outer ring grouting

Abstract

The present invention relates to the field of tunnel engineering, and specifically to a method and system for calculating the lateral earth pressure adjacent to a foundation pit under the action of grouting outside the tunnel ring. The method comprises the following steps: obtaining the concentrated force on the surface of the grouting body outside the tunnel ring and the stress-strain relationship of the soil; obtaining the lateral additional stress of the support pile under the action of grouting based on the concentrated force; obtaining the active earth pressure of the support pile based on the stress-strain relationship; obtaining the lateral earth pressure adjacent to the foundation pit under the action of grouting outside the tunnel ring through the lateral additional stress and the active earth pressure. The present invention realizes the accurate calculation of the lateral earth pressure adjacent to the foundation pit under the action of grouting outside the tunnel ring by comprehensively analyzing the influence of the grouting body on the displacement and earth pressure of the support pile, and provides an important theoretical basis for the design and construction of tunnel engineering.

Description

Technical Field

[0001] The invention relates to the field of tunnel engineering, and in particular to a method and system for calculating the lateral earth pressure of an adjacent foundation pit under the action of grouting outside a tunnel ring. Background Art

[0002] In modern urban construction, with the massive development of underground projects such as subways and underground passages, the mutual influence between tunnels and foundation pits has become increasingly prominent. Especially in densely populated urban areas, tunnel and foundation pit construction are often closely linked. The soil displacement and stress generated during foundation pit excavation often have a significant impact on the stability of adjacent tunnel structures, causing deformation or even damage to the tunnel. In order to address this issue, the engineering community continues to explore effective technical means to ensure the safety and stability of underground projects.

[0003] As an effective method for tunnel deformation correction, tunnel outer ring grouting technology has been widely used in the field of tunnel engineering in recent years. This technology mainly targets tunnel sections that have been deformed or displaced. It injects high-strength, curable grouting materials into the outer space of the tunnel ring through the grouting body, and uses the expansion force of the grouting material and the supporting effect after curing to actively or passively reinforce the tunnel, effectively correct tunnel deformation, and restore its original structure and function.

[0004] However, the grouting process not only changes the stress state of the tunnel itself, but also has a complex impact on the adjacent foundation pit support structure through the soil. This impact includes but is not limited to the change in the lateral earth pressure of the foundation pit support structure, the internal force and deformation of the support structure, etc., which are directly related to the safety and stability of the foundation pit project. Therefore, how to accurately calculate the lateral earth pressure adjacent to the foundation pit under the action of grouting and evaluate the impact of grouting on the foundation pit support structure have become key technical issues that need to be solved in current tunnel and foundation pit projects.

[0005] In the prior art, the lateral earth pressure of the foundation pit support structure is usually calculated based on traditional earth pressure theories, such as Coulomb's earth pressure theory and Rankine's earth pressure theory. However, these theories have obvious shortcomings. First, there are certain limitations in the calculation of soil characteristics after grouting and foundation pit excavation, and it is difficult to accurately reflect the changes in lateral earth pressure under the action of grouting; second, it does not comprehensively consider factors such as grouting, soil characteristics and foundation pit excavation, which makes it difficult to accurately predict and evaluate the lateral earth pressure adjacent to the foundation pit under the action of grouting outside the tunnel ring; third, it can only provide static calculation results, and it is difficult to achieve real-time monitoring and early warning of lateral earth pressure changes under grouting, which increases safety risks and is not conducive to timely response measures.

[0006] At present, there is not much research on the lateral earth pressure adjacent to the foundation pit under the action of grouting, and there is no specific, accurate and reliable method to calculate the lateral earth pressure adjacent to the foundation pit under the action of grouting outside the tunnel ring. Summary of the invention

[0007] In view of the defects in the prior art, the present invention provides a method and system for calculating the lateral earth pressure of an adjacent foundation pit under the action of grouting outside a tunnel ring.

[0008] In a first aspect, the present invention provides a method for calculating the lateral earth pressure of a foundation pit adjacent to the tunnel ring under the action of grouting outside the tunnel ring, comprising the following steps: obtaining the concentrated force on the surface of the tunnel ring grouting body and the stress-strain relationship of the soil; obtaining the lateral additional stress of the support pile under the action of grouting according to the concentrated force; obtaining the active earth pressure of the support pile based on the stress-strain relationship; obtaining the lateral earth pressure of the foundation pit adjacent to the tunnel ring under the action of grouting outside the tunnel ring through the lateral additional stress and the active earth pressure, wherein the lateral earth pressure satisfies the following expression:

[0009] ,

[0010] in, Indicates the depth of soil outside the tunnel ring The lateral earth pressure of the foundation pit adjacent to the grouting at Indicates soil depth The soil pressure of the supporting piles under the grouting action at Indicates soil depth The present invention provides a reliable data basis for soil pressure calculation by obtaining the concentrated force on the surface of the grouting body outside the tunnel ring and the stress-strain relationship of the soil, thereby ensuring the accuracy of the calculation results; by combining the calculation of the lateral additional stress of the supporting piles under the action of grouting, and the derivation of the active soil pressure of the supporting piles based on the stress-strain relationship, the influence of grouting on soil pressure is fully considered, thereby improving the comprehensiveness of soil pressure calculation; by using the lateral additional stress and the active soil pressure, the lateral soil pressure adjacent to the foundation pit under the action of grouting outside the tunnel ring is calculated, which provides an important reference basis for the design and construction of foundation pit support and helps to ensure the safety and stability of tunnel engineering; by comprehensively considering the joint action of the active soil pressure and the grouting soil pressure, the actual influence of the grouting outside the tunnel ring on the lateral soil pressure of the foundation pit is accurately reflected; by comprehensively considering multiple factors such as soil properties, grouting action and foundation pit excavation, the calculation results are closer to the actual situation, which helps to better evaluate and control the stability of the foundation pit during the design and construction process.

[0011] Optionally, the method of obtaining the additional lateral stress of the support pile under the action of grouting according to the concentrated force includes: simplifying the grouting body formed by the inner ring grouting into a rectangular block, and the grouting pressure inside the rectangular block is evenly distributed; substituting the concentrated forces on the four faces of the rectangular block into the expression of the Mindlin solution for calculation to obtain four calculation results; adding the four calculation results to obtain the additional lateral stress of the support pile under the action of grouting. The present invention greatly simplifies the calculation process and improves the calculation efficiency by simplifying the grouting body into a uniformly stressed rectangular block, while maintaining the accuracy of the calculation results; using the expression of the Mindlin solution to calculate the additional lateral stress on the support pile caused by the concentrated forces on the four faces of the rectangular block, accurately reflects the influence of the grouting body on the support pile; by adding the calculation results of the four faces, the additional lateral stress of the support pile under the action of grouting is comprehensively obtained, ensuring the comprehensiveness and accuracy of the calculation, and providing a solid foundation for the subsequent soil pressure calculation.

[0012] Optionally, the additional lateral stress satisfies the following expression:

[0013] ,

[0014] in, represents the additional lateral stress of the supporting pile under the grouting action, It indicates the additional lateral stress on the support pile caused by the concentrated force on the left side of the grouting body under grouting action. It indicates the additional lateral stress on the support pile caused by the concentrated force on the grouting body under the grouting action. It indicates the additional lateral stress on the support pile caused by the concentrated force on the right side of the grouting body under grouting action. It represents the additional lateral stress on the supporting piles caused by the concentrated force under the grouting body under the grouting action. The present invention makes the calculation process clearer and more organized by clarifying the contribution of the concentrated force on each surface of the grouting body to the additional lateral stress on the supporting piles; by summing up, the additional lateral stress in each direction is integrated into a unified value, which is convenient for subsequent analysis and application; this expression is not only applicable to specific grouting bodies and supporting pile conditions, but also has a certain degree of versatility, which helps to improve the safety and reliability of engineering design and construction.

[0015] Optionally, the active earth pressure of the supporting piles is obtained based on the stress-strain relationship, including: establishing a relationship between the displacement and strain of the supporting piles caused by excavation based on the stress-strain relationship; and obtaining the active earth pressure of the supporting piles under excavation according to the relationship. The present invention accurately quantifies the deformation of the supporting piles during the excavation process by constructing a relationship between the displacement and strain of the supporting piles caused by excavation, thereby providing a reliable basis for subsequent earth pressure calculations; the active earth pressure borne by the supporting piles under excavation is derived by utilizing the relationship between the displacement and strain of the supporting piles, thereby ensuring the accuracy of the calculation results; a complete mechanical analysis system is formed by closely linking the displacement, strain and active earth pressure of the supporting piles, thereby helping to fully understand the force characteristics and deformation laws of the supporting piles during the excavation process.

[0016] Optionally, the expression of the active earth pressure is as follows:

[0017] ,

[0018] in, Indicates soil depth The active earth pressure of the supporting piles under the excavation action at Indicates soil weight. represents the static earth pressure coefficient, Indicates soil depth The soil influence range is is the soil Poisson’s ratio, , represents the soil material constant, Indicates soil depth The displacement of the supporting piles caused by the excavation at the site satisfies the following functional relationship:

[0019] ,

[0020] in, Indicates soil depth The displacement of the supporting piles caused by the excavation at , , It represents the function coefficient, and the method for determining the function coefficient includes an indirect method and a direct method; the indirect method determines the function coefficient by fitting data based on the deformation experience of the support structure and the maximum allowable deformation of the support piles; the direct method determines the function coefficient by fitting data based on the monitoring data of the excavation to a certain stage. The present invention comprehensively reflects the complexity of active earth pressure of supporting piles under excavation by including soil depth, soil weight, static earth pressure coefficient, soil influence range, soil Poisson's ratio, soil material constant and supporting pile displacement parameters caused by excavation into the calculation scope; by accurately calculating the active earth pressure borne by supporting piles at different depths, an important basis is provided for the design and construction of supporting structures; through this expression, not only the theoretical system of soil pressure calculation is enriched, but also new ideas and methods are provided for solving related soil engineering problems; by introducing supporting pile displacement function to describe the displacement change of supporting piles with soil depth, it is conducive to accurately analyzing the deformation behavior of supporting piles; the indirect method uses the deformation experience of supporting structure and the maximum allowable deformation value to perform data fitting, which provides a convenient way for the preliminary determination of function coefficients; the direct method determines function coefficients through data fitting based on actual monitoring data during excavation, ensures the accuracy and practicality of the function, and provides a reliable basis for the prediction and evaluation of supporting pile displacement.

[0021] Optionally, the lateral earth pressure adjacent to the foundation pit under the action of grouting outside the tunnel ring is obtained through the lateral additional stress and the active earth pressure, including: obtaining the grouting earth pressure through the active earth pressure; obtaining the lateral earth pressure adjacent to the foundation pit under the action of grouting outside the tunnel ring through the lateral additional stress and the grouting earth pressure. The present invention provides basic data for the calculation of grouting earth pressure through active earth pressure, so that the change of soil layer pressure during grouting can be quantified; by introducing lateral additional stress, the influence of foundation pit excavation and grouting construction factors on soil stress is fully considered, so that the calculation result is closer to reality and the accuracy of engineering design is improved; by combining active earth pressure and lateral additional stress, the lateral earth pressure adjacent to the foundation pit is comprehensively calculated, which provides a scientific basis for the safety control of grouting construction outside the tunnel ring.

[0022] Optionally, the use of the active earth pressure to obtain the grouting earth pressure includes: using the active earth pressure to obtain the displacement of the supporting piles caused by the grouting action; obtaining the additional displacement of the supporting piles caused by the grouting action according to the displacement of the supporting piles and the additional lateral stress of the supporting piles under the grouting action; adding the additional displacement of the supporting piles and the displacement of the supporting piles caused by the excavation action to obtain the total displacement of the supporting piles caused by the grouting action; and obtaining the grouting earth pressure through the total displacement. The present invention accurately calculates the displacement of the supporting piles caused by the grouting action through the active earth pressure, providing a scientific basis for in-depth understanding of the influence of grouting on the supporting piles; combining the additional lateral stress of the supporting piles under the grouting action, fully considering the complex mechanical effects of grouting, and accurately calculating the additional displacement of the supporting piles caused by grouting; by combining the displacement of the supporting piles caused by the excavation action and the grouting action, the total displacement of the supporting piles under the grouting action is obtained, and the grouting earth pressure is successfully derived based on this, which not only improves the accuracy of the grouting earth pressure calculation, but also provides strong support for the safety assessment of foundation pit engineering.

[0023] Optionally, the expression of the grouting soil pressure is as follows:

[0024] ,

[0025] in, Indicates soil depth The soil pressure of the supporting pile under the grouting action at Indicates soil weight. represents the static earth pressure coefficient, Indicates soil depth The displacement of the supporting piles caused by the excavation and grouting action at the Indicates soil depth The soil influence range is is the soil Poisson’s ratio, , Represents the soil material constant. The present invention fully considers the influence of the soil's own properties on the soil pressure by introducing the static earth pressure coefficient and soil weight, making the calculation result more in line with the actual situation and helping to analyze the changing law of soil pressure under different construction conditions; by introducing the soil influence range, Poisson's ratio, soil material constant and considering the influence of soil space effect, the accuracy and reliability of soil pressure calculation are further improved.

[0026] In the second aspect, the present invention provides a system for calculating the lateral earth pressure of a foundation pit adjacent to the tunnel under the action of grouting outside the ring, including an input device, a processor, an output device and a memory, wherein the input device, the processor, the output device and the memory are interconnected, wherein the memory is used to store a computer program, the computer program includes program instructions, the processor is configured to call the program instructions, and the system uses the method for calculating the lateral earth pressure of a foundation pit adjacent to the tunnel under the action of grouting outside the ring. The system for calculating the lateral earth pressure of a foundation pit adjacent to the tunnel under the action of grouting outside the ring provided by the present invention has a high degree of integration and smooth information transmission between various components. By integrating the calculation modules of lateral additional stress and grouting earth pressure, accurate prediction of soil pressure changes under complex geological and construction conditions is achieved; the calculation results can be quickly obtained by inputting relevant parameters, which greatly improves work efficiency; through powerful data analysis functions, the calculation results are deeply mined and visualized, providing engineers with comprehensive and intuitive decision support, which helps to optimize construction plans and ensure the stability of foundation pits and construction safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a flow chart of a method for calculating the lateral earth pressure of a foundation pit adjacent to the tunnel under the action of grouting outside the tunnel ring according to an embodiment of the present invention;

[0028] Figure 2 It is a schematic diagram of the overall structure of a tunnel ring, soil layer, support piles and foundation pit according to an embodiment of the present invention;

[0029] Figure 3 A schematic diagram of a supporting pile structure according to an embodiment of the present invention;

[0030] Figure 4 A diagram showing displacement changes of supporting piles caused by grouting soil pressure and lateral additional stress according to an embodiment of the present invention;

[0031] Figure 5 It is a structural schematic diagram of a system for calculating the lateral earth pressure adjacent to a foundation pit under the action of grouting outside a tunnel ring according to an embodiment of the present invention. DETAILED DESCRIPTION

[0032] The specific embodiments of the present invention will be described in detail below. It should be noted that the embodiments described herein are only for illustration and are not intended to limit the present invention. In the following description, a large number of specific details are set forth in order to provide a thorough understanding of the present invention. However, it is obvious to those of ordinary skill in the art that these specific details do not need to be adopted to implement the present invention. In other examples, in order to avoid confusing the present invention, known circuits, software or methods are not specifically described.

[0033] Throughout the specification, references to "one embodiment," "an embodiment," "an example," or "an example" mean that a particular feature, structure, or characteristic described in conjunction with the embodiment or example is included in at least one embodiment of the present invention. Therefore, the phrases "in one embodiment," "in an embodiment," "an example," or "an example" appearing in various places throughout the specification do not necessarily all refer to the same embodiment or example. In addition, particular features, structures, or characteristics may be combined in one or more embodiments or examples in any suitable combination and / or subcombination. In addition, it should be understood by those of ordinary skill in the art that the figures provided herein are for illustrative purposes and that the figures are not necessarily drawn to scale.

[0034] See also Figure 1 The embodiment of the present invention provides a method for calculating the lateral earth pressure of a foundation pit adjacent to a tunnel under the action of grouting outside the tunnel ring, the method comprising the following steps:

[0035] S1. Obtain the relationship between the concentrated force on the surface of the grouting body outside the tunnel ring and the stress-strain relationship of the soil outside the tunnel ring.

[0036] Among them, S1 includes the following steps:

[0037] S11. Obtain the concentrated force on the surface of the grouting body outside the tunnel ring.

[0038] See also Figure 2 , Figure 2 The overall structure diagram of the tunnel ring, soil layer, support piles and foundation pit of the embodiment of the present invention is shown in FIG. represents the distance between the top of the tunnel ring and the top of the soil layer, represents the radius of the tunnel ring, represents the uniformly distributed stress on the grouting body, represents the length of the grouting body, Indicates the width of the grouting body, It indicates the distance between the ground where the foundation pit is located and the top of the soil layer. represents the additional lateral stress of the supporting pile under the grouting action, Indicates the height of the soil layer based on the ground. Indicates the distance between the support pile and one end of the grouting body. , Represents the plane coordinate axes.

[0039] In one embodiment, the grouting body outside the tunnel ring is simplified as a rectangular block. Assuming that the grouting pressure inside the block is uniformly distributed, we have:

[0040] ,

[0041] in, represents the uniformly distributed stress on the grouting body, Represents the overall grouting pressure in the grouting hole. Indicates the length of the grouting body, Indicates the width of the grouting body.

[0042] Furthermore, according to Saint-Venant's principle, the uniformly distributed stress acting on the surface of the grouting body can be treated as a concentrated force, and then:

[0043] ,

[0044] in, It represents the concentrated force acting on the left side of the grouting body, and the point of action of the concentrated force is , It represents the concentrated force acting on the grouting body, and the point of action of the concentrated force is , It represents the concentrated force acting on the right side of the grouting body, and the point of action of the concentrated force is , It represents the concentrated force acting under the grouting body, and the point of action of the concentrated force is , Indicates the density of the grouting liquid. Indicates the height of the soil layer based on the ground. represents the length of the grouting body, Indicates the width of the grouting body, Indicates the depth of grouting.

[0045] S12. Obtain the stress-strain relationship of the soil outside the tunnel ring.

[0046] In one embodiment, the stress-strain relationship of the soil outside the tunnel ring is obtained by consulting the data. The stress-strain relationship is as follows:

[0047] ,

[0048] in, represents the average normal stress, represents the first principal strain, , They represent the maximum principal stress and minimum principal stress at a point in the soil, respectively. , They represent the maximum principal stress and minimum principal stress when the soil reaches the yield or failure state, , represents the soil material constant. Among them, the soil material constant Satisfies the following expression:

[0049] ,

[0050] in, Represents the elastic modulus of soil, which satisfies the following expression:

[0051] ,

[0052] in, Indicates soil weight. represents the atmospheric pressure, represents the modulus coefficient, Indicates the soil depth, Represents the modulus index.

[0053] Furthermore, the soil constant Satisfies the following expression:

[0054] ,

[0055] in, It represents the stress difference of soil at the time of failure. represents the internal friction angle of soil, Represents soil cohesion.

[0056] Furthermore, the average normal stress of the soil satisfies the following expression:

[0057] ,

[0058] S2. Based on the concentrated force, the additional lateral stress of the supporting pile under the action of grouting is obtained.

[0059] Among them, S2 includes the following steps:

[0060] S21. Substitute the concentrated forces on the four surfaces of the grouting body into the expression of Mindlin's solution to calculate and obtain four calculation results.

[0061] At a point in the half infinite space Apply concentrated load When , based on the Mindlin solution, any point in the space can be solved The stress expression is:

[0062] ,

[0063] ,

[0064] ,

[0065] in, Satisfies the following relationship:

[0066] ,

[0067] Satisfies the following relationship:

[0068] ,

[0069] Satisfies the following relationship:

[0070] ,

[0071] Satisfies the following relationship:

[0072] ,

[0073] Satisfies the following expression:

[0074] ,

[0075] Satisfies the following expression:

[0076] ,

[0077] Satisfies the following expression:

[0078] ,

[0079] Satisfies the following expression:

[0080] ,

[0081] Satisfies the following expression:

[0082] ,

[0083] Satisfies the following expression:

[0084] ,

[0085] in, , , , , , , , , , are all intermediate variables. for Shear stress in the direction for The normal stress in the direction, for Shear stress in the plane, is the Poisson's ratio of soil.

[0086] Furthermore, the concentrated forces on the four surfaces of the grouting body are substituted into the expression of the Mindlin solution for calculation, and four calculation results are obtained, which are: , , , .

[0087] S22. Add the four calculation results to obtain the additional lateral stress of the support pile under the action of grouting.

[0088] In one embodiment, the lateral additional stress components generated by the concentrated forces on the four surfaces of the grouting body under the grouting action on the supporting pile are added together to obtain the lateral additional stress of the supporting pile under the grouting action. The lateral additional stress satisfies the following expression:

[0089] ,

[0090] in, represents the additional lateral stress of the supporting pile under the grouting action, It indicates the additional lateral stress on the support pile caused by the concentrated force on the left side of the grouting body under grouting action. It indicates the additional lateral stress on the support piles caused by the concentrated force on the grouting body under grouting action. It indicates the additional lateral stress on the support pile caused by the concentrated force on the right side of the grouting body under grouting action. It indicates the additional lateral stress on the supporting piles caused by the concentrated force below the grouting body during grouting.

[0091] S3. Based on the stress-strain relationship, the active earth pressure of the supporting pile is obtained.

[0092] S3 includes the following steps:

[0093] S31. Based on the stress-strain relationship, a relationship between the displacement and strain of the support piles caused by excavation is established.

[0094] On a macro scale, the accumulation of strain forms displacement. Assuming that within the soil disturbance zone, the horizontal strain of the soil decreases linearly along the direction away from the foundation pit enclosure, the connection between enclosure deformation and strain can be established.

[0095] In one embodiment, based on the stress-strain relationship obtained in step S1, a relationship between the displacement of the supporting piles and the strain caused by the excavation is established. The relationship between the displacement of the supporting piles and the strain caused by the excavation is as follows:

[0096] ,

[0097] in, Indicates soil depth The displacement of the supporting piles at Indicates soil depth The horizontal strain of the soil at Indicates soil depth The soil influence range at , which satisfies the following expression:

[0098] ,

[0099] in, Indicates the angle, It represents the angle between the left boundary of the soil influence range and the horizontal direction.

[0100] Furthermore, the horizontal strain and support pile displacement Satisfies the following relationship:

[0101] ,

[0102] S32. According to the relationship, the active earth pressure of the supporting piles under the excavation action is obtained.

[0103] See also Figure 3 , Figure 3 Schematic diagram of the supporting pile structure of an embodiment of the present invention. Indicates soil depth The soil influence range is is the active earth pressure of the soil, Indicates the angle, It represents the angle between the left boundary of the soil influence range and the horizontal direction.

[0104] In one embodiment, the active earth pressure of the supporting piles under the excavation action is obtained according to the relationship between the displacement and strain of the supporting piles caused by the excavation action established in step S31.

[0105] Specifically, for the soil unit behind the wall, before the foundation pit is excavated, the following relationship is satisfied:

[0106] ,

[0107] ,

[0108] in, Indicates soil weight. represents the static earth pressure coefficient, is the soil depth, , They respectively represent the major principal stress and minor principal stress of the soil outside the pit before excavation.

[0109] Furthermore, after the foundation pit excavation work is completed, the following relationship is satisfied:

[0110] ,

[0111] ,

[0112] in, , They represent the major principal stress and minor principal stress of a point in the soil, respectively. Represents active earth pressure.

[0113] Further, combining the stress-strain relationship in step S1, the relationship between active earth pressure and strain is obtained, which is as follows:

[0114] ,

[0115] in, Indicates soil depth The active earth pressure at , represents the soil material constant, represents horizontal strain.

[0116] Furthermore, in combination with the relationship between the displacement and strain of the supporting pile in step S31, the relationship between the active earth pressure and the displacement of the supporting pile is obtained, and the relationship is as follows:

[0117] ,

[0118] in, Indicates soil depth The active earth pressure of the supporting piles under the excavation action at Indicates soil weight. represents the static earth pressure coefficient, Indicates soil depth The soil influence range is is the soil Poisson’s ratio, , represents the soil material constant, Indicates soil depth The displacement of the supporting piles caused by the excavation at the site satisfies the following functional relationship:

[0119] ,

[0120] in, Indicates soil depth The displacement of the supporting piles caused by the excavation at , , It represents the function coefficient, which is determined according to the actual support form difference. The method for determining the function coefficient includes an indirect method and a direct method;

[0121] The indirect method performs data fitting based on the deformation experience of the support structure and the maximum deformation allowed by the support piles to determine the function coefficients;

[0122] The direct method performs data fitting based on monitoring data at a certain stage of excavation to determine the function coefficients.

[0123] S4. The lateral earth pressure adjacent to the foundation pit under the action of grouting outside the tunnel ring is obtained through the lateral additional stress and the active earth pressure.

[0124] Wherein, step S4 further comprises the following steps:

[0125] S41. Obtain the grouting soil pressure through the active soil pressure.

[0126] In one embodiment, the relationship between active earth pressure and support pile displacement is rearranged to obtain:

[0127] ,

[0128] in, The soil depth It should be noted that this relationship transforms the relationship between active earth pressure and support pile displacement into the relationship between support pile displacement and additional lateral stress of support pile under grouting.

[0129] Furthermore, the additional lateral stress acting on the supporting structure during the actual grouting process is substituted into the relationship between the active earth pressure and the displacement of the supporting piles to obtain the additional deformation caused by the grouting effect, that is, the additional displacement of the supporting piles caused by the grouting effect.

[0130] Furthermore, the additional displacement of the supporting pile and the displacement of the supporting pile caused by the excavation are added together to obtain the total displacement of the supporting pile caused by the grouting effect. The total displacement of the supporting pile satisfies the following expression:

[0131] ,

[0132] in, Indicates soil depth The total displacement of the supporting piles caused by the grouting at Indicates soil depth The displacement of the supporting piles caused by the excavation at Indicates soil depth Additional displacement of supporting piles caused by grouting at

[0133] Furthermore, the total displacement is substituted into the relationship between the active earth pressure and the displacement of the supporting pile in step S32 to obtain the grouting earth pressure, and the expression of the grouting earth pressure is as follows:

[0134] ,

[0135] in, Indicates soil depth The soil pressure of the supporting pile under the grouting action at Indicates soil weight. represents the static earth pressure coefficient, Indicates soil depth The displacement of the supporting piles caused by the excavation and grouting action at the Indicates soil depth The soil influence range is is the soil Poisson’s ratio, , Represents the soil material constant.

[0136] S42. The lateral soil pressure adjacent to the foundation pit under the action of grouting outside the tunnel ring is obtained through the lateral additional stress and the grouting soil pressure.

[0137] In one embodiment, the lateral additional stress and the grouting soil pressure are added to obtain the lateral soil pressure adjacent to the foundation pit under the action of grouting outside the tunnel ring, and the lateral soil pressure satisfies the following expression:

[0138] ,

[0139] in, Indicates the depth of soil outside the tunnel ring The lateral earth pressure of the foundation pit adjacent to the grouting at Indicates soil depth The soil pressure of the supporting pile under the grouting action at Indicates soil depth The additional lateral stress of the support pile under the grouting action at the position. The displacement of the support pile caused by the additional lateral stress and the grouting soil pressure is as follows: Figure 4 shown.

[0140] See also Figure 5 , Figure 5The present invention is a schematic diagram of the structure of a system for calculating the lateral earth pressure of a foundation pit adjacent to the tunnel ring under the effect of grouting outside the tunnel ring according to an embodiment of the present invention. The system includes an input device, a processor, an output device and a memory, wherein the input device, the processor, the output device and the memory are interconnected, wherein the memory is used to store a computer program, the computer program includes program instructions, the processor is configured to call the program instructions, and the system uses the method for calculating the lateral earth pressure of a foundation pit adjacent to the tunnel ring under the effect of grouting outside the tunnel ring.

[0141] In this embodiment, the input device is used to input various data information, and the data information includes grouting pressure, soil weight, Poisson's ratio, and soil cohesion.

[0142] The processor has built-in various mathematical algorithms, including Mindlin solution, additional lateral stress of support piles caused by grouting, support pile displacement and earth pressure algorithm.

[0143] The output device uses a display screen to display the calculation results processed by the processor.

[0144] The memory adopts a high-speed solid-state hard disk to store data information input by the input device and calculation results processed by the processor. It has the characteristics of fast reading and writing speed, large capacity and high reliability, and can meet the needs of large data storage.

[0145] In summary, the method for calculating the lateral earth pressure adjacent to the foundation pit under the action of grouting outside the tunnel ring provided by the present invention provides a reliable data basis for earth pressure calculation by obtaining the concentrated force on the surface of the grouting body inside the tunnel ring and the stress-strain relationship of the soil outside the tunnel ring, thereby ensuring the accuracy of the calculation results; by combining the calculation of the lateral additional stress of the supporting piles under the action of grouting, and the derivation of the active earth pressure of the supporting piles based on the stress-strain relationship, the influence of grouting on the earth pressure is fully considered, thereby improving the comprehensiveness of the earth pressure calculation; by integrating the lateral additional stress and the grouting earth pressure, the lateral earth pressure adjacent to the foundation pit under the action of grouting outside the tunnel ring is obtained, which provides an important reference basis for the design and construction of foundation pit support, and helps to ensure the safety and stability of foundation pit projects.

[0146] The lateral earth pressure calculation system adjacent to the foundation pit under the action of tunnel outer ring grouting provided by the present invention realizes accurate prediction of earth pressure changes under complex geological and construction conditions by integrating calculation modules of lateral additional stress and grouting earth pressure; the calculation results can be quickly obtained by inputting relevant parameters, which greatly improves work efficiency; through powerful data analysis functions, the calculation results are deeply mined and visualized, providing engineers with comprehensive and intuitive decision-making support, which helps to optimize construction plans and ensure foundation pit stability and construction safety.

[0147] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. These modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be included in the scope of the claims and specification of the present invention.

Claims

1. A method for calculating the lateral earth pressure of the adjacent foundation pit under the action of grouting outside the tunnel ring, characterized in that: The method comprises the following steps: Obtain the relationship between the concentrated force on the surface of the grouting body outside the tunnel ring and the stress-strain relationship of the soil; According to the concentrated force, the lateral additional stress of the supporting pile under the grouting action is obtained; Based on the stress-strain relationship, the active earth pressure of the supporting pile is obtained; The lateral earth pressure of the foundation pit adjacent to the tunnel ring under the action of grouting outside the tunnel ring is obtained through the lateral additional stress and the active earth pressure; the lateral earth pressure of the foundation pit adjacent to the tunnel ring under the action of grouting outside the tunnel ring is obtained through the lateral additional stress and the active earth pressure, including: obtaining the grouting earth pressure through the active earth pressure; the grouting earth pressure through the active earth pressure includes: obtaining the displacement of the supporting piles caused by the grouting action through the active earth pressure; obtaining the additional displacement of the supporting piles caused by the grouting action according to the displacement of the supporting piles and the lateral additional stress of the supporting piles under the grouting action; adding the additional displacement of the supporting piles and the displacement of the supporting piles caused by the excavation action to obtain the total displacement of the supporting piles caused by the grouting action; obtaining the grouting earth pressure through the total displacement; The lateral soil pressure adjacent to the foundation pit under the action of grouting outside the tunnel ring is obtained through the lateral additional stress and the grouting soil pressure; the expression of the grouting soil pressure is as follows: in, Indicates soil depth The soil pressure of the supporting pile under the grouting action at Indicates soil weight. represents the static earth pressure coefficient, Indicates soil depth The displacement of the supporting piles caused by the excavation and grouting action at the Indicates soil depth The soil influence range is is the soil Poisson’s ratio, , represents the soil material constant; the lateral earth pressure satisfies the following expression: in, Indicates the depth of soil outside the tunnel ring The lateral earth pressure of the foundation pit adjacent to the grouting at Indicates soil depth The soil pressure of the supporting pile under the grouting action at Indicates soil depth Additional lateral stress of supporting piles under the action of grouting at .

2. The method for calculating the lateral earth pressure of the adjacent foundation pit under the action of tunnel outer ring grouting according to claim 1 is characterized in that: The method of obtaining the lateral additional stress of the support pile under the grouting action according to the concentrated force includes: The grouting body formed by the grouting in the ring is simplified into a rectangular block, and the grouting pressure inside the rectangular block is evenly distributed; Substituting the concentrated forces on the four faces of the rectangular block into the expression of the Mindlin solution for calculation, four calculation results are obtained; The four calculation results are added together to obtain the lateral additional stress of the supporting pile under the grouting action.

3. The method for calculating the lateral earth pressure of the adjacent foundation pit under the action of tunnel outer ring grouting according to claim 2 is characterized in that: The additional lateral stress satisfies the following expression: in, represents the additional lateral stress of the supporting pile under the grouting action, It indicates the additional lateral stress on the support pile caused by the concentrated force on the left side of the grouting body under grouting action. It indicates the additional lateral stress on the support piles caused by the concentrated force on the grouting body under grouting action. It indicates the additional lateral stress on the support pile caused by the concentrated force on the right side of the grouting body under grouting action. It indicates the additional lateral stress on the supporting piles caused by the concentrated force below the grouting body during grouting.

4. The method for calculating the lateral earth pressure of the adjacent foundation pit under the action of tunnel outer ring grouting according to claim 1 is characterized in that: The method of obtaining the active earth pressure of the support pile based on the stress-strain relationship includes: Based on the stress-strain relationship, a relationship between the displacement and strain of the support pile caused by excavation is established; According to the relationship, the active earth pressure of the supporting piles under the excavation action is obtained.

5. The method for calculating the lateral earth pressure of the adjacent foundation pit under the action of tunnel outer ring grouting according to claim 4 is characterized in that: The expression of active earth pressure is as follows: in, Indicates soil depth The active earth pressure of the supporting piles under the excavation action at Indicates soil weight. represents the static earth pressure coefficient, Indicates soil depth The soil influence range is is the soil Poisson’s ratio, , represents the soil material constant, Indicates soil depth The displacement of the supporting piles caused by the excavation at the site satisfies the following functional relationship: in, Indicates soil depth The displacement of the supporting piles caused by the excavation at , , represents a function coefficient, wherein the method for determining the function coefficient includes an indirect method and a direct method; The indirect method performs data fitting based on the deformation experience of the support structure and the maximum deformation allowed by the support piles to determine the function coefficients; The direct method performs data fitting based on monitoring data at a certain stage of excavation to determine the function coefficients.

6. A system for calculating the lateral earth pressure of a foundation pit adjacent to a tunnel under the action of grouting outside the tunnel ring, the system using a method for calculating the lateral earth pressure of a foundation pit adjacent to a tunnel under the action of grouting outside the tunnel ring according to any one of claims 1 to 5, characterized in that: The system includes an input device, a processor, an output device and a memory, wherein the input device, the processor, the output device and the memory are connected to each other, wherein the memory is used to store a computer program, the computer program includes program instructions, and the processor is configured to call the program instructions.

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