Method, system and device for calculating anti-bulging stability of circular shaft structure and medium

Abstract

The application discloses a kind of round shaft structure anti-heave stability calculation method, system, equipment and medium, and the method comprises the following steps: determining the basic parameters of round shaft structure, and the basic parameters include the diameter of round shaft, foundation pit excavation depth, retaining structure embedded depth, soil cohesion, soil internal friction angle, soil specific weight and ground uniform load;According to the basic parameters, the bearing capacity coefficient and are calculated;The bottom sliding soil of round shaft structure is divided into Rankine active zone, Rankine passive zone and transition zone, and the geometric parameters of Rankine active zone, Rankine passive zone and transition zone are determined, and the influence width outside pit is determined based on the basic parameters and geometric parameters;Based on the basic parameters, bearing capacity coefficient and influence width outside pit, the anti-heave safety factor of round shaft foundation pit is calculated by formula.The application can determine the anti-heave safety factor of round shaft foundation pit, and the determined safety factor can better reflect the actual situation.

Description

Technical Field

[0001] This invention belongs to the field of foundation pit technology, and particularly relates to a method, system, equipment and medium for calculating the anti-uplift stability of a circular vertical shaft structure. Background Technology

[0002] According to the explanatory notes of the "Technical Specification for Foundation Pit Support" (JGJ120-2012), the method used for verifying the stability against heave is the Prandtl limit equilibrium theory formula, which is currently widely used and based on the ultimate bearing capacity of the foundation. However, some assumptions in the Prandtl theory formula differ from actual conditions, thus limiting its application. For example, if the embedment depth of the retaining structure is particularly small, this formula cannot be used to verify the stability of the pit bottom heave.

[0003] This is because Prandtl's theoretical formula does not consider the resistance of soil gravity in the sliding zone below the bottom of the retaining structure to heave, thus making the heave resistance safety factor unrelated to the slip line depth. The calculated safety factor is the same for shallow and deep slip bodies, which deviates to some extent from reality. Furthermore, in related calculations, the weight of the soil above the bottom of the retaining structure outside the foundation pit is simplified to a flexible uniformly distributed load acting on that plane, and the resistance of shear stress in this part of the soil to heave is ignored.

[0004] In practice, for shallow slipways, the shear stress in the soil above the bottom plane of the retaining structure significantly increases the heave resistance safety factor. However, as the slipway extends deeper, while the proportion of this shear stress in the total resistance to heave gradually decreases, the weight of the soil within the slip zone gradually increases in its role in resisting heave. If the resistance of soil shear force to heave is considered in the heave resistance calculation formula, the vertical stress in the soil at the bottom plane of the retaining structure will decrease. Consequently, the earth pressure acting on the retaining structure will increase accordingly, undoubtedly reducing the safety of the support structure. Therefore, the heave stability calculation formula in this code does not consider the beneficial effect of this shear stress.

[0005] The Terzaghi method in the "Technical Standard for Foundation Pit Engineering" (DG / TJ08-61-2018) and the manual "Review of Design Methods for Excavation" is suitable for shallower or wider excavations (i.e., H / B < 1). However, this method does not consider the beneficial effect of the retaining structure below the pit bottom on resisting uplift.

[0006] It is evident that current methods for calculating heave stability have shortcomings and problems: (1) The effect of the planar dimensions of the foundation pit was not considered. The standard uses the classical Prandtl or Terzaghi theories to calculate the heave resistance safety factor, but does not consider the influence of the length-to-width ratio and excavation area of ​​the pit on the sliding surface. Narrow pits (such as strip pits) have significant spatial effects, and their actual heave resistance may be higher than the calculated results, leading to conservative design; while large pits (such as square or circular pits) may underestimate the heave risk due to two-dimensional simplification.

[0007] (2) Limitations of the two-dimensional computational model The standard is based on the plane strain assumption, assuming the sliding surface is a two-dimensional circular arc, and does not cover three-dimensional failure modes. In actual engineering, the corners of the foundation pit usually have higher resistance to uplift than the middle due to spatial constraints, but the standard does not provide differentiated verification methods.

[0008] (3) Insufficient applicability of the project For ultra-deep and ultra-large foundation pits (such as subway hubs), standard methods may underestimate the extent of plastic zone development. Without supplementary verification using finite element analysis or three-dimensional limit equilibrium methods, it is difficult to reflect the actual progressive failure process of soil. Summary of the Invention

[0009] The purpose of this invention is to provide a method, system, equipment and medium for calculating the heave stability of a circular vertical shaft structure, which can determine the heave safety factor of the circular vertical shaft foundation pit, and the determined safety factor can better reflect the actual situation and better ensure the safety of the project.

[0010] This invention is achieved through the following technical solution: A method for calculating the heave stability of a circular vertical shaft structure, applicable when the plastic zones of a circular vertical shaft have overlapping influence zones, includes the following steps: Determine the basic parameters of the circular shaft structure, including the diameter of the circular shaft, the excavation depth of the foundation pit, the embedment depth of the retaining structure, the soil cohesion, the internal friction angle of the soil, the soil weight, and the uniformly distributed load on the ground. The bearing capacity coefficient is calculated based on the basic parameters. The bearing capacity coefficient includes... , and ; Based on the principle of ultimate bearing capacity, the sliding soil mass at the bottom of the circular shaft structure is divided into the Rankine active zone, the Rankine passive zone, and the transition zone. The geometric parameters of the Rankine active zone, the Rankine passive zone, and the transition zone are determined, and the influence width outside the pit is determined based on the basic parameters and geometric parameters. ; Based on basic parameters, bearing capacity coefficient, and width of external influence. The heave resistance safety factor of the circular vertical shaft foundation pit is calculated using formula (1): (1); In the formula, The safety factor for the stability of a circular foundation pit against uplift. The cohesion of the soil below the bottom surface of the retaining structure. The internal friction angle of the soil below the bottom surface of the retaining member. The embedment depth of the retaining structure. This refers to the depth of the foundation pit excavation. The unit weight of the soil above the bottom surface of the retaining structure outside the foundation pit is the natural weight of the soil. The unit weight of the soil above the bottom surface of the retaining structure within the foundation pit is the natural weight of the soil. The unit weight of the soil below the bottom surface of the retaining structure. This refers to the resistance of shear stress in the soil above the bottom of the retaining structure outside the foundation pit to the heave. The load is a uniformly distributed load on the ground.

[0011] Furthermore, the geometric parameters include the active slip surface inclination angle, the passive slip surface inclination angle, the active region radial shear surface deflection angle, and the passive region radial shear surface deflection angle; The width of external influence based on basic parameters and geometric parameters is determined. The steps include: Based on the basic parameters and geometric parameters, the width of the external influence of the pit is calculated using formula (2). : (2); In the formula, The diameter of the circular shaft, The internal friction angle of the soil. The angle of the passive slip surface. The radial shear plane deflection angle in the passive region. For the active slip surface dip angle, This represents the radial shear plane deflection angle in the active region.

[0012] Furthermore, the steps for calculating the bearing capacity coefficient based on the basic parameters include: Based on the basic parameters, the bearing capacity coefficient is calculated using the following formula: (3); (4); (5); In the formula, The friction angle within the soil.

[0013] Furthermore, the derivation process of formula (1) is as follows: The formula for ultimate bearing capacity is derived from Terzaghi's theory of ultimate bearing capacity of foundations: (6); Since the heave can only slide from one side, the influence of the unit weight of the foundation soil should be twice the conventional ultimate bearing capacity of the foundation. Considering the cross-influence of the soil weight at the bottom of the pit on the other side, only half of the influence can be considered, resulting in: (7); Furthermore, consider the resistance of shear stress in the soil above the bottom of the retaining structure outside the foundation pit to the heave. : (8); In the formula, Let denoted as Rankine's active earth pressure coefficient, and z be the length of the circular diaphragm wall below ground level. The cohesion of the soil above the bottom surface of the retaining structure outside the foundation pit. The internal friction angle of the soil above the bottom surface of the retaining structure outside the foundation pit; From formula (8): (9); calculate : (10); Combining the above formulas, we obtain formula (1): (1).

[0014] This invention also provides a system for calculating the heave stability of a circular shaft structure, comprising: The determination module is used to determine the basic parameters of the circular shaft structure. The basic parameters include the diameter of the circular shaft, the excavation depth of the foundation pit, the embedment depth of the retaining structure, the soil cohesion, the internal friction angle of the soil, the soil weight, and the uniformly distributed load on the ground. The first calculation module is used to calculate the bearing capacity coefficient based on basic parameters, including the bearing capacity coefficient. , and ; The second calculation module is used to divide the sliding soil at the bottom of the circular shaft structure into the Rankine active zone, the Rankine passive zone, and the transition zone according to the principle of ultimate foundation bearing capacity, and to determine the geometric parameters of the Rankine active zone, the Rankine passive zone, and the transition zone. Based on the basic parameters and geometric parameters, the width of the influence outside the pit is determined. ; The third calculation module is used to calculate based on basic parameters, bearing capacity coefficient, and width of external impact. The heave resistance safety factor of the circular vertical shaft foundation pit is calculated using formula (1): (1); In the formula, The safety factor for the stability of a circular foundation pit against uplift. The cohesion of the soil below the bottom surface of the retaining structure. The internal friction angle of the soil below the bottom surface of the retaining member. The embedment depth of the retaining structure. This refers to the depth of the foundation pit excavation. The unit weight of the soil above the bottom surface of the retaining structure outside the foundation pit is the natural weight of the soil. The unit weight of the soil above the bottom surface of the retaining structure within the foundation pit is the natural weight of the soil. The unit weight of the soil below the bottom surface of the retaining structure. This refers to the resistance of shear stress in the soil above the bottom of the retaining structure outside the foundation pit to the heave. The load is a uniformly distributed load on the ground.

[0015] The present invention also discloses an electronic device, which includes: processor; Memory is used to store executable computer programs; Among them, the steps of implementing the method for calculating the anti-uplift stability of a circular vertical shaft structure when the processor executes the computer program.

[0016] The present invention also discloses a computer-readable storage medium storing a computer program thereon, wherein the computer program, when executed by a processor, implements the steps of a method for calculating the anti-uplift stability of a circular shaft structure.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows: it takes into account the influence of the diameter size of the circular shaft, considers the influence of the foundation width in the anti-heave stability calculation formula, and also considers the resistance of shear stress in the soil above the bottom of the retaining structure of the foundation pit to heave. Therefore, the determined anti-heave safety factor of the circular shaft foundation pit can better reflect the actual working conditions, the calculation results are more in line with the actual situation, and can better guarantee the safety of the project. Attached Figure Description

[0018] Figure 1 This is a flowchart illustrating the steps of the method for calculating the heave stability of a circular vertical shaft structure according to the present invention. Figure 2 A schematic diagram showing the overlapping influence zones within the plastic region; Figure 3 A simplified diagram for calculating the heave resistance of a circular vertical shaft structure; Figure 4 This is a schematic diagram of the module of the circular vertical shaft structure anti-heave stability calculation system of the present invention; Figure 5 This is a hardware structure diagram of the electronic device of the present invention. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0020] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0021] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, in the description of this invention, terms such as "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0022] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes the element.

[0023] In the description of this invention, it should be noted that the terms "upper," "lower," "inner," "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of this invention is usually placed when in use. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0024] Please see Figure 1 and Figure 2 , Figure 1 This is a flowchart illustrating the steps of the method for calculating the heave stability of a circular vertical shaft structure according to the present invention. Figure 2This is a schematic diagram illustrating the overlapping influence zones within the plastic zone. A method for calculating the heave stability of a circular shaft structure is presented, applicable to cases where the plastic zone of a circular shaft exhibits overlapping influence zones, such as... Figure 2 As shown, Figure 2 The figure shows the plastic zone contour map calculated using the strength reduction method. The dashed line in the figure represents the outer contour of the plastic zone and can be considered as the heave failure line. The calculation method for the heave stability of a circular shaft structure includes the following steps: S1. Determine the basic parameters of the circular shaft structure. The basic parameters include the diameter of the circular shaft, the excavation depth of the foundation pit, the embedment depth of the retaining structure, the soil cohesion, the internal friction angle of the soil, the soil weight, and the uniformly distributed load on the ground. S2. Calculate the bearing capacity coefficient based on the basic parameters. The bearing capacity coefficient includes... , and ; S3. Based on the principle of ultimate bearing capacity of foundation, the sliding soil at the bottom of the circular shaft structure is divided into the Rankine active zone, the Rankine passive zone, and the transition zone. The geometric parameters of the Rankine active zone, the Rankine passive zone, and the transition zone are determined. Based on the basic parameters and geometric parameters, the width of the influence outside the pit is determined. ; S4. Based on basic parameters, bearing capacity coefficient, and width of external impact. The heave resistance safety factor of the circular vertical shaft foundation pit is calculated using formula (1): (1); In the formula, The safety factor for the stability of a circular foundation pit against uplift. The cohesion of the soil below the bottom surface of the retaining structure. The internal friction angle of the soil below the bottom surface of the retaining member. The embedment depth of the retaining structure. This refers to the depth of the foundation pit excavation. The unit weight of the soil above the bottom surface of the retaining structure outside the foundation pit is the natural weight of the soil. The unit weight of the soil above the bottom surface of the retaining structure within the foundation pit is the natural weight of the soil. The unit weight of the soil below the bottom surface of the retaining structure. This refers to the resistance of shear stress in the soil above the bottom of the retaining structure outside the foundation pit to the heave. The load is a uniformly distributed load on the ground.

[0025] In step S1 above, the diameter of the circular shaft structure is determined based on the construction drawings and the corresponding engineering geological survey report. Excavation depth of the foundation pit Retaining structure embedment depth Soil cohesion , soil internal friction angle The soil weight includes the natural unit weight of the soil above the bottom surface of the retaining structure outside the foundation pit. The natural unit weight of the soil above the bottom surface of the retaining structure in the foundation pit and the natural unit weight of the soil below the bottom surface of the retaining structure Soil cohesion and soil internal friction angle can also be further subdivided according to actual needs. For example, soil cohesion includes the cohesion of the soil below the bottom surface of the retaining member and the cohesion of the soil above the bottom surface of the retaining member outside the foundation pit. Soil internal friction angle includes the internal friction angle of the soil below the bottom surface of the retaining member and the internal friction angle of the soil above the bottom surface of the retaining member outside the foundation pit.

[0026] In step S2 above, you can refer to the textbook "Soil Mechanics" (e.g., "Soil Mechanics" (3rd edition) edited by Li Guangxin, Zhang Bingyin, and Yu Yuzhen, Tsinghua University Press), and refer to the bearing capacity coefficient in Hansen's ultimate bearing capacity formula. , and Calculate the bearing capacity coefficient , and Furthermore, the bearing capacity coefficient is calculated using the following formula. , and : (3); (4); (5); In the formula, The friction angle within the soil.

[0027] In step S3 above, referring to the composition of the slip network of the ultimate bearing capacity foundation of Prandtl L, 1920 and Reissner H, 1924, such as... Figure 3 As shown, the sliding soil mass can be divided into three regions: Region I, Region II, and Region III. Region I is the Rankine active region, Region III is the Rankine passive region, and Region II is the transition region. The geometric parameters of the Rankine active region, Rankine passive region, and transition region can be determined from this. Then, the relevant angles are obtained based on the triangular geometric relationship of Region III. The parameters of the transition region are calculated using the logarithmic spiral function of Region II. Finally, the value of B is determined from the triangular geometric relationship of Region I. B is the width of the external influence (m) during the heave stability verification, which is a function of the diameter of the circular shaft, i.e., B = f( ), The diameter of the circular shaft.

[0028] Furthermore, such as Figure 3As shown, the geometric parameters include the active slip surface inclination angle ∠dce, the passive slip surface inclination angle ∠acb, the active region radial shear surface deflection angle ∠cde, and the passive region radial shear surface deflection angle ∠abc. Determine the width of external influence based on basic and geometric parameters. The steps include: In the Rankine active region (I region) of CDE, ∠dce = ∠dec = 45° + / 2, ∠cde = 90°- ; According to the Law of Sines, we can obtain: (11); Therefore, we get: (12); In the transition region II of bcd, ∠bcd = 90°; (13); Substituting formula (12) into (13) yields: (14); In the Rankine passive region (region III) of ABC, ∠acb = ∠bac = 45° - / 2, ∠abc = 90°+ ; According to the Law of Sines, we can obtain: (15); Based on the above geometric relationships, we can obtain: (16); Therefore: (17); We can obtain: (2); In the formula, The diameter of the circular shaft, The internal friction angle of the soil. The angle of the passive slip surface. The radial shear plane deflection angle in the passive region. For the active slip surface dip angle, This represents the radial shear plane deflection angle in the active region.

[0029] Therefore, the width of the external influence of the pit can be calculated using formula (2). .

[0030] In step S4 above, the obtained basic parameters, bearing capacity coefficient, and external influence width B are substituted into formula (1) to calculate the heave resistance safety factor. With safety factor A safety assessment of anti-uplift stability is conducted. Specifically, the safety factor is... Compared with the safety levels required by the standard, the "Technical Specification for Foundation Pit Support" (JGJ120-2012) stipulates that for support with safety levels of I, II, and III, the uplift safety factors should not be less than 1.8, 1.6, and 1.4, respectively. Therefore, when the safety level of the foundation pit project is I, if the safety factor... A value greater than or equal to 1.8 indicates that the heave stability meets the specification requirements. If the safety factor... A value less than 1.8 indicates that the heave stability does not meet the specifications; when the foundation pit project is of grade II, if the safety factor is... A value greater than or equal to 1.6 indicates that the heave stability meets the specification requirements. If the safety factor... A value less than 1.6 indicates that the heave stability does not meet the specifications; when the foundation pit project is of grade three, if the safety factor is... A value greater than or equal to 1.4 indicates that the heave resistance stability meets the specification requirements. If the safety factor... A value less than 1.4 indicates that the anti-heave stability does not meet the specification requirements.

[0031] Furthermore, the derivation of formula (1) is as follows: The formula for ultimate bearing capacity is derived from Terzaghi's theory of ultimate bearing capacity of foundations: (6); Since the heave can only slide from one side, the influence of the unit weight of the foundation soil should be twice the conventional ultimate bearing capacity of the foundation. Considering the cross-influence of the soil weight at the bottom of the pit on the other side, only half of the influence can be considered, resulting in: (7); Furthermore, consider the resistance of shear stress in the soil above the bottom of the retaining structure outside the foundation pit to the heave. : (8); In the formula, This is Rankine's active earth pressure coefficient. z is the distance of the circular diaphragm wall measured from the ground surface downwards, that is, the length of the circular diaphragm wall below the ground surface. The cohesion of the soil above the bottom surface of the retaining structure outside the foundation pit. It is the internal friction angle of the soil above the bottom surface of the retaining structure outside the foundation pit.

[0032] From formula (8): (9); calculate : (10); Combining the above formulas, we obtain formula (1): (1).

[0033] Please refer to the following: Figure 4 , Figure 4 This is a schematic diagram of the module of the circular shaft structure anti-heave stability calculation system of the present invention. Corresponding to the aforementioned embodiments of the circular shaft structure anti-heave stability calculation method of the present invention, the present invention also provides a circular shaft structure anti-heave stability calculation system, including: Module 1 is used to determine the basic parameters of the circular shaft structure. The basic parameters include the diameter of the circular shaft, the excavation depth of the foundation pit, the embedment depth of the retaining structure, the soil cohesion, the internal friction angle of the soil, the soil weight, and the uniformly distributed load on the ground. The first calculation module 2 is used to calculate the bearing capacity coefficient based on basic parameters, including the bearing capacity coefficient. , and ; The second calculation module 3 is used to divide the sliding soil at the bottom of the circular shaft structure into the Rankine active zone, the Rankine passive zone, and the transition zone according to the principle of ultimate foundation bearing capacity, and to determine the geometric parameters of the Rankine active zone, the Rankine passive zone, and the transition zone. Based on the basic parameters and geometric parameters, it determines the width of the influence outside the pit. ; The third calculation module 4 is used to calculate based on basic parameters, bearing capacity coefficient, and width of external impact. The heave resistance safety factor of the circular vertical shaft foundation pit is calculated using formula (1): (1); In the formula, The safety factor for the stability of a circular foundation pit against uplift. The cohesion of the soil below the bottom surface of the retaining structure. The internal friction angle of the soil below the bottom surface of the retaining member. The embedment depth of the retaining structure. This refers to the depth of the foundation pit excavation. The unit weight of the soil above the bottom surface of the retaining structure outside the foundation pit is the natural weight of the soil. The unit weight of the soil above the bottom surface of the retaining structure within the foundation pit is the natural weight of the soil. The unit weight of the soil below the bottom surface of the retaining structure. This refers to the resistance of shear stress in the soil above the bottom of the retaining structure outside the foundation pit to the heave. The load is a uniformly distributed load on the ground.

[0034] Furthermore, the geometric parameters include the active slip surface dip angle, the passive slip surface dip angle, the active region radial shear surface deflection angle, and the passive region radial shear surface deflection angle; The second calculation module 3 includes: The first calculation unit is used to calculate the width of the external influence of the pit based on the basic parameters and geometric parameters using formula (2). : (2); In the formula, The diameter of the circular shaft, The internal friction angle of the soil. The angle of the passive slip surface. The radial shear plane deflection angle in the passive region. For the active slip surface dip angle, This represents the radial shear plane deflection angle in the active region.

[0035] Furthermore, the first computing module 2 includes: The second calculation unit is used to calculate the bearing capacity coefficient based on the basic parameters using the following formula: (3); (4); (5); In the formula, The friction angle within the soil.

[0036] The implementation process of the functions and roles of each module and unit in the above system is detailed in the implementation process of the corresponding steps in the above method, and will not be repeated here. For the system embodiment, since it basically corresponds to the method embodiment, relevant parts can be referred to in the description of the method embodiment. The system embodiment described above is merely illustrative; the units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units.

[0037] Corresponding to the aforementioned embodiments of the circular shaft structure anti-uplift stability calculation method, this invention also provides an electronic device, which may include: a processor; and a memory for storing an executable computer program; wherein, when the processor executes the computer program, it implements the circular shaft structure anti-uplift stability calculation method in any of the aforementioned method embodiments. The embodiments of the circular shaft structure anti-uplift stability calculation system provided by this invention can all be applied to electronic devices. Taking software implementation as an example, as a logical device, it is formed by the processor of the electronic device reading the corresponding computer program instructions from the non-volatile memory into the memory for execution. From a hardware perspective, as shown in Figure 5, in addition to the processor, memory, network interface, and non-volatile memory shown in Figure 5, the electronic device may also include other hardware, such as a camera module; or, depending on the actual function of the electronic device, it may also include other hardware, which will not be elaborated further.

[0038] Corresponding to the aforementioned embodiment of the method for calculating the anti-uplift stability of a circular shaft structure, this embodiment of the invention also provides a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the steps of the method for calculating the anti-uplift stability of a circular shaft structure.

[0039] Embodiments of the present invention may take the form of a computer program product implemented on one or more storage media containing program code (including but not limited to disk storage, CD-ROM, optical storage, etc.). The computer-readable storage medium may include: permanent or non-permanent removable or non-removable media. The information storage function of the computer-readable storage medium can be implemented by any feasible method or technology. The information may be computer-readable instructions, data structures, program models, or other data.

[0040] In addition, computer-readable storage media include, but are not limited to: phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic disk storage or other magnetic storage devices, or other non-transfer media that can be used to store information accessible by a computing device.

[0041] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Therefore, any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A method for calculating the heave stability of a circular vertical shaft structure, characterized in that, When the plastic zones of a circular shaft have overlapping influence zones, the method includes the following steps: Determine the basic parameters of the circular shaft structure, including the diameter of the circular shaft, the excavation depth of the foundation pit, the embedment depth of the retaining structure, the soil cohesion, the internal friction angle of the soil, the soil weight, and the uniformly distributed load on the ground. The bearing capacity coefficient is calculated based on the basic parameters. The bearing capacity coefficient includes... , and ; Based on the principle of ultimate bearing capacity, the sliding soil mass at the bottom of the circular shaft structure is divided into the Rankine active zone, the Rankine passive zone, and the transition zone. The geometric parameters of the Rankine active zone, the Rankine passive zone, and the transition zone are determined, and the influence width outside the pit is determined based on the basic parameters and geometric parameters. ; Based on basic parameters, bearing capacity coefficient, and width of external influence. The heave resistance safety factor of the circular vertical shaft foundation pit is calculated using formula (1): （1）； In the formula, The safety factor for the stability of a circular foundation pit against uplift. The cohesion of the soil below the bottom surface of the retaining structure. The internal friction angle of the soil below the bottom surface of the retaining member. The embedment depth of the retaining structure. This refers to the depth of the foundation pit excavation. The unit weight of the soil above the bottom surface of the retaining structure outside the foundation pit is the natural weight of the soil. The unit weight of the soil above the bottom surface of the retaining structure within the foundation pit is the natural weight of the soil. The unit weight of the soil below the bottom surface of the retaining structure. This refers to the resistance of shear stress in the soil above the bottom of the retaining structure outside the foundation pit to the heave. The load is uniformly distributed on the ground. The geometric parameters include the active slip surface inclination angle, the passive slip surface inclination angle, the active region radial shear surface deflection angle, and the passive region radial shear surface deflection angle. The width of external influence based on basic parameters and geometric parameters is determined. The steps include: Based on the basic parameters and geometric parameters, the width of the external influence of the pit is calculated using formula (2). : （2）； In the formula, The diameter of the circular shaft, The internal friction angle of the soil. The dip angle of the passive slip surface. The radial shear plane deflection angle in the passive region. For the active slip surface dip angle, This represents the radial shear plane deflection angle in the active region.

2. The method for calculating the heave stability of a circular vertical shaft structure according to claim 1, characterized in that, The step of calculating the bearing capacity coefficient based on basic parameters includes: Based on the basic parameters, the bearing capacity coefficient is calculated using the following formula: （3）； （4）； （5）； In the formula, The friction angle within the soil.

3. The method for calculating the heave stability of a circular vertical shaft structure according to claim 1, characterized in that, The derivation process of formula (1) is as follows: The formula for ultimate bearing capacity is derived from Terzaghi's theory of ultimate bearing capacity of foundations: （6）； Since the heave can only slide from one side, the influence of the unit weight of the foundation soil should be twice the conventional ultimate bearing capacity of the foundation. Considering the cross-influence of the soil weight at the bottom of the pit on the other side, only half of the influence can be considered, resulting in: （7）； Furthermore, consider the resistance of shear stress in the soil above the bottom of the retaining structure outside the foundation pit to the heave. : （8）； In the formula, Let denoted as Rankine's active earth pressure coefficient, and z be the length of the circular diaphragm wall below ground level. The cohesion of the soil above the bottom surface of the retaining structure outside the foundation pit. The internal friction angle of the soil above the bottom surface of the retaining structure outside the foundation pit; From formula (8): （9）； calculate : （10）； Combining the above formulas, we obtain formula (1): （1）。 4. A system for calculating the anti-uplift stability of a circular vertical shaft structure, characterized in that, include: The determination module is used to determine the basic parameters of the circular shaft structure. The basic parameters include the diameter of the circular shaft, the excavation depth of the foundation pit, the embedment depth of the retaining structure, the soil cohesion, the internal friction angle of the soil, the soil weight, and the uniformly distributed load on the ground. The first calculation module is used to calculate the bearing capacity coefficient based on basic parameters, including the bearing capacity coefficient. , and ; The second calculation module is used to divide the sliding soil at the bottom of the circular shaft structure into the Rankine active zone, the Rankine passive zone, and the transition zone according to the principle of ultimate foundation bearing capacity, and to determine the geometric parameters of the Rankine active zone, the Rankine passive zone, and the transition zone. Based on the basic parameters and geometric parameters, the width of the influence outside the pit is determined. ; The third calculation module is used to calculate based on basic parameters, bearing capacity coefficient, and width of external impact. Furthermore, consider the resistance of shear stress in the soil above the bottom of the retaining structure outside the foundation pit to the heave. The heave resistance safety factor of the circular vertical shaft foundation pit is calculated using formula (1): （1）； In the formula, The safety factor for the stability of a circular foundation pit against uplift. The cohesion of the soil below the bottom surface of the retaining structure. The internal friction angle of the soil below the bottom surface of the retaining member. The embedment depth of the retaining structure. This refers to the depth of the foundation pit excavation. The unit weight of the soil above the bottom surface of the retaining structure outside the foundation pit is the natural weight of the soil. The unit weight of the soil above the bottom surface of the retaining structure within the foundation pit is the natural weight of the soil. The unit weight of the soil below the bottom surface of the retaining structure. This refers to the resistance of shear stress in the soil above the bottom of the retaining structure outside the foundation pit to the heave. The load is uniformly distributed on the ground. The geometric parameters include the active slip surface inclination angle, the passive slip surface inclination angle, the active region radial shear surface deflection angle, and the passive region radial shear surface deflection angle. The second calculation module includes: The first calculation unit is used to calculate the width of the external influence of the pit based on the basic parameters and geometric parameters using formula (2). : （2）； In the formula, The diameter of the circular shaft, The internal friction angle of the soil. The dip angle of the passive slip surface. The radial shear plane deflection angle in the passive region. For the active slip surface dip angle, This represents the radial shear plane deflection angle in the active region.

5. An electronic device, characterized in that, include: processor; Memory is used to store executable computer programs; Wherein, when the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 3.

6. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 3.

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