Design method of anchor plug body skewback

Abstract

The invention relates to a design method of an anchor body skewback, which comprises the following steps of: calculating the constraint stiffness Ki of each rock stratum in an unloading zone to a pile body by initially simulating various parameters of the anchor body skewback and fully considering the influence of the unloading zone on the stress state of an anchor body according to a bed rock bearing stratum depth value L1 of the anchor body skewback crossing the unloading zone and an M method; according to the constraint stiffness Ki of each rock stratum to the pile body within the unloading zone and each parameter of the anchor body skewback, an anchor body skewback macroscopic finite element model considering the pile-soil effect is established, namely, the anchor body skewback macroscopic finite element model fully considers the influence of the unloading zone on the stress state of the anchor body; and the radial constraint effect of an unloading zone and an outer foundation rock mass on the anchor plug body is not considered any more, so that whether the bearing capacities of the section A, the section B, the section C and the section D and the bearing capacity of the foundation meet the requirements or not is checked, and the designed anchor plug body skewback is safer in structural stress and more reasonable in design.

Description

Technical Field

[0001] This invention relates to the field of arch seat design technology, and in particular to a design method for an anchor plug arch seat. Background Technology

[0002] As my country's highway construction extends into the western mountainous regions, long-span bridges are increasingly used to cross mountain valleys, with arch bridges being widely adopted due to their economic efficiency, high load-bearing capacity, and strong spanning ability. However, in the southwestern mountainous areas, the construction of long-span bridges faces complex topographical and geological conditions. Constrained by these adverse geological conditions, conventional arch abutment foundation structures are ill-suited to construction needs, necessitating the development of a new type of arch abutment foundation adapted to complex topographical and geological conditions. Existing arch abutment foundation structures all employ reinforced concrete enlarged arch abutments. These abutments are set on the foundation rock mass. To ensure sufficient bearing area at the abutment base to resist the internal forces transmitted from the superstructure of the arch bridge, the dimensions of these abutments must be sufficiently large to meet the foundation's load-bearing requirements.

[0003] Existing reinforced concrete enlarged arch abutment structures are large in size. When the slope at the bridge site is relatively steep, the construction of the arch abutment set in the foundation rock mass requires a large amount of slope excavation. For steep slopes with unloading fissures or bedding slopes and other adverse geological conditions, large excavations can easily cause slope instability and create geological risks. Currently, Chinese patent application CN116180558A discloses an arch abutment and its construction method. The arch abutment includes an embedded section, a force transmission section, and a connecting section arranged sequentially along its length. The embedded section is located within the unloading zone of the slope, the force transmission section is located between the unloading zone and the excavated slope surface, and the connecting section is located outside the excavated slope surface. The embedded section, force transmission section, and connecting section are integrally formed reinforced concrete structures. The connecting section is used to connect the arch foot of the main arch. Its excavation range is small, the use risk is lower, and its applicability is higher. The top of the arch seat is provided with prestressed steel strands along its length. Because the anchor body arch seat is adapted to the arch foot to form an oblique arrangement, prestress is provided at the top to avoid the stress of tension at the upper end and compression at the lower end under the weight of the connecting section during construction, so that the connecting section is always under compression. The top of the cross section of the anchor body arch seat is set as an arc.

[0004] The aforementioned arch abutment can reduce structural dimensions while meeting foundation stress requirements, thus solving the aforementioned problems. However, there is currently no design method for this type of anchor-plug arch abutment. Existing arch abutment design methods do not involve unloading zones, so the impact of unloading zones on arch abutment design is not considered. Furthermore, there is no reference in the existing technology regarding the impact of unloading zones on arch abutment design, making it impossible for existing arch abutment design methods to meet the design requirements of this arch abutment. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of existing arch seat design methods, which do not involve unloading zones and therefore do not consider the impact of unloading zones on arch seat design. Furthermore, existing technologies lack references regarding the impact of unloading zones on arch seat design, making existing arch seat design methods unable to meet the design deficiencies of the arch seat. This invention provides a design method for an anchor plug arch seat.

[0006] In a first aspect, the present invention provides a design method for an anchor body arch, the anchor body arch comprising an embedded section, a force transmission section and a connecting section continuously arranged axially from the inside to the outside, the upper end face of the connecting section being section A, the interface between the connecting section and the force transmission section being section B, the interface between the force transmission section and the embedded section being section C, and the lower end face of the embedded section being section D. The design methodology includes the following steps: S1. Preliminary parameters of the anchor body arch, including the depth of the bedrock bearing layer across the unloading zone L1, the axial length L of the anchor body arch, the center height H1 of section A, the bottom width B1 of section A, the center height H2 of section B, the bottom width B2 of section B, the center height H3 of section C, the bottom width B3 of section C, the center height H4 of section D, the bottom width B4 of section D, and the radius R of the top arc of the cross-section of the anchor body arch. The bedrock bearing layer depth L1 across the unloading zone of the anchor body arch seat is used to calculate the constraint stiffness Ki of each rock layer within the unloading zone on the pile body according to the M method. S2. Based on the constraint stiffness Ki of each rock layer within the unloading zone on the pile body and the various parameters of the anchor body arch, establish a macroscopic finite element model of the anchor body arch considering the pile-soil effect. S3. Input the structural internal force load transmitted from the main arch to the anchor body arch seat. The macroscopic finite element model calculates the internal forces of sections A, B, C and D of the anchor body arch seat, as well as the axial force at the lower end of the anchor body arch seat's embedded section. S4. Verify whether the bearing capacity of sections A, B, C, and D is greater than the internal forces of sections A, B, C, and D. If the bearing capacity of sections A, B, C, and D is less than or equal to the corresponding internal forces of sections A, B, C, and D, then return to step S1 to increase the center height and bottom width of the corresponding section of the anchor body arch. Verification of foundation bearing capacity Whether it is greater than the axial force at the lower end of the anchor-supported arch section, if the foundation bearing capacity If the axial force is less than or equal to the lower end of the anchor body arch seat embedment section, then return to step S1 and increase the bedrock bearing layer depth value L1 of the anchor body arch seat across the unloading zone. After returning to step S1, repeat steps S2-S4 until: the bearing capacity of sections A, B, C, and D are all greater than the internal forces of sections A, B, C, and D, and the bearing capacity of the foundation is also greater. It is greater than the axial force at the lower end of the anchor block arch seat embedment section.

[0007] Preferably, in step S1, the parameters of the anchor block arch seat are initially calculated based on the internal forces and arch foot dimensions of the main arch.

[0008] Preferably, in step S1, the depth of the bedrock bearing layer L1 of the unloading zone of the anchor body arch seat and the soil lateral resistance are used as the basis for the calculation. The constraint stiffness Ki of each rock layer within the unloading zone on the pile body is calculated according to the M method.

[0009] Preferably, soil lateral resistance Obtained from the foundation information at the anchor body arch seat. Preferably, the macroscopic finite element model of the anchor block arch is established as follows: Based on the various parameters of the anchor body arch, a macroscopic rod element model of the anchor body arch reflecting the material and cross-sectional properties is established. Consolidation constraints are applied to the lower end of the anchor body arch in the macro-bar unit model of the anchor body arch; and constraint stiffness Ki of each rock layer within the unloading zone is applied perpendicularly to the axis of the anchor body arch within the bedrock bearing layer depth value L1 of the anchor body arch across the unloading zone in the macro-bar unit model of the anchor body arch.

[0010] Preferably, in step S3, the structural internal force load transmitted from the main arch to the anchor block arch seat includes axial force N, longitudinal bending moment My, transverse bending moment Mz, and shear force V.

[0011] Preferably, the shear force V is an in-plane shear force perpendicular to the axial force N and located on the arch face of the anchor body arch seat.

[0012] Preferably, in step S4, the bearing capacity of sections A, B, C and D is calculated based on various parameters of the anchor body arch. Foundation bearing capacity The calculation formula is:

[0013] In the formula, The end drag utilization coefficient; Let D be the cross-sectional area; The standard value of the saturated uniaxial compressive strength of the rock at the lower end of the anchor body arch; The perimeter of the anchorage arch corresponding to each soil or rock layer within the unloading zone; The lateral resistance utilization coefficient of the i-th rock layer within the unloading zone; The thickness of each rock layer within the unloading zone of the anchor body arch; The standard value of the saturated uniaxial compressive strength of the rock in the i-th layer within the unloading zone is obtained based on the foundation information at the anchor body arch seat; i = 1, 2, ..., m; The coefficient for lateral resistance utilization of the overburden soil; Let be the thickness of the j-th soil layer. Let be the standard value of the lateral resistance of the j-th soil layer; j = 1, 2, ..., n.

[0014] Preferably, in step S4, the bearing capacity of the foundation is first verified. Whether it is greater than the axial force at the lower end of the anchor-supported arch section, if the foundation bearing capacity If the axial force is less than or equal to the axial force at the lower end of the anchor-supported arch section, return to step S1, increase the bedrock bearing layer depth L1 across the unloading zone of the anchor-support arch, and then repeat steps S2-S4 until the foundation bearing capacity is reached. Greater than the axial force at the lower end of the anchor block arch seat embedment section; If the bearing capacity of the foundation is greater than the axial force at the lower end of the anchor-supported arch section, then check whether the bearing capacity of sections A, B, C, and D is greater than the internal forces of sections A, B, C, and D. If at least one of the bearing capacities of sections A, B, C, and D is less than or equal to the corresponding internal forces of sections A, B, C, and D, then return to step S1 to increase the center height and bottom width of the corresponding sections of the anchor-supported arch. Then repeat steps S2-S4 until the bearing capacity of sections A, B, C, and D is greater than the corresponding internal forces of sections A, B, C, and D.

[0015] Preferably, after step S4, step S5 is further included: calculating the internal forces of section B of the anchor bolt arch when only the self-weight load of the anchor bolt arch is applied using the macroscopic finite element model of the anchor bolt arch; configuring the prestressed steel strands at the top of the anchor bolt arch based on the internal forces of section B of the anchor bolt arch when only the self-weight load of the anchor bolt arch is applied; verifying whether the bearing capacity of section B of the anchor bolt arch meets the requirements; if it does not meet the requirements, reconfiguring the prestressed steel strands of the anchor bolt arch until the requirements are met.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention provides a design method for an anchor-type arch seat. By initially determining the parameters of the anchor-type arch seat and fully considering the influence of the unloading zone on the stress state of the anchor-type body, the method uses the depth L1 of the bedrock bearing layer spanning the unloading zone of the anchor-type arch seat and calculates the constraint stiffness Ki of each rock layer within the unloading zone on the pile body according to the M method. Based on the constraint stiffness Ki of each rock layer within the unloading zone on the pile body and the parameters of the anchor-type arch seat, a macroscopic finite element model of the anchor-type arch seat considering the pile-soil effect is established. This ensures that the macroscopic finite element model of the anchor-type arch seat fully considers the influence of the unloading zone on the stress state of the anchor-type body and no longer considers the radial constraint effect of the foundation rock mass outside the unloading zone on the anchor-type body. The bearing capacity of sections A, B, C, and D, and the bearing capacity of the foundation are then verified. Whether all requirements are met makes the structure of the anchor block arch seat more secure and the design more reasonable. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the anchor bolt arch structure; Figure 2 This is a schematic diagram of section A of the anchor bolt arch. Figure 3 This is a schematic diagram of section B of the anchor bolt arch. Figure 4 This is a schematic diagram of section C of the anchor bolt arch. Figure 5 This is a schematic diagram of section D of the anchor bolt arch. The markings in the diagram are: 1. Fixed section; 2. Force transmission section; 3. Connecting section; 4. Prestressed steel strand. Detailed Implementation

[0018] The present invention will now be described in further detail with reference to specific embodiments. However, this should not be construed as limiting the scope of the present invention to the following embodiments; all technologies implemented based on the content of the present invention fall within the scope of the present invention.

[0019] Unless otherwise specified, the use of terms such as "upper," "lower," "left," "right," "center," "inner," and "outer" to indicate orientation or positional relationships in the description of specific embodiments of the present invention is based on the orientation or positional relationships shown in the accompanying drawings, or the orientation or positional relationship in which the product / equipment / device is typically placed during use. These terms are merely for the purpose of facilitating the description of the present invention or simplifying the description in specific embodiments, enabling those skilled in the art to quickly understand the solution, and do not indicate or imply that a particular device / component / element must have a specific orientation, or be constructed and operated in a specific positional relationship. Therefore, they should not be construed as limitations on the present invention.

[0020] Furthermore, the use of terms such as "horizontal," "vertical," "suspended," and "parallel" does not imply that the corresponding device / component / element must be absolutely horizontal, vertical, suspended, or parallel, but rather that it can be slightly tilted or have a deviation. For example, "horizontal" merely means that its direction is more horizontal relative to "vertical," not that the structure must be completely horizontal, but that it can be slightly tilted. Alternatively, it can be simplified to mean that the corresponding device / component / element, when set in a "horizontal," "vertical," "suspended," or "parallel" direction, can have an error / deviation of ±10% relative to the corresponding direction, more preferably within ±8%, more preferably within ±6%, more preferably within ±5%, and more preferably within ±4%. As long as the corresponding device / component / element is within the error / deviation range, it can still achieve its function in the present invention.

[0021] Furthermore, the use of terms such as "first," "second," and "third" in terminology is merely for distinguishing descriptions of identical or similar components and should not be interpreted as emphasizing or implying the relative importance of a particular component.

[0022] Furthermore, in the description of the embodiments of the present invention, "several", "more than", and "a number of" represent at least two. The number can be any number, such as 2, 3, 4, 5, 6, 7, 8, or 9, and can even exceed nine.

[0023] Furthermore, in the description of the technical solution of this invention, unless otherwise explicitly specified / limited / restricted, the terms "set up," "install," "connect," "link," "provided with," "laid out," and "arranged" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to common connection methods in the art, such as welding, riveting, bolting, and threaded connections. Such connections can be mechanical, electrical, or communication connections; they can be direct connections or indirect connections through an intermediate medium; and they can refer to the internal communication between two components.

[0024] Example 1 This embodiment provides a design method for an anchor plug arch seat, such as Figures 1-5 As shown, the anchor body arch includes a fixed section 1, a force transmission section 2 and a connecting section 3 continuously arranged from the inside to the outside along the axial direction. The upper end face of the connecting section 3 is section A, the interface between the connecting section 3 and the force transmission section 2 is section B, the interface between the force transmission section 2 and the fixed section 1 is section C, and the lower end face of the fixed section 1 is section D. The design methodology includes the following steps: S1. Preliminary parameters of the anchor body arch, including the depth of the bedrock bearing layer across the unloading zone L1, the axial length L of the anchor body arch, the center height H1 of section A, the bottom width B1 of section A, the center height H2 of section B, the bottom width B2 of section B, the center height H3 of section C, the bottom width B3 of section C, the center height H4 of section D, the bottom width B4 of section D, and the radius R of the top arc of the cross-section of the anchor body arch. In an optional implementation, the depth of the bedrock bearing layer L1 across the unloading zone of the anchor body arch seat is ≥5m to ensure bearing capacity.

[0025] In an optional implementation, in step S1, the parameters of the anchor body arch seat are initially determined based on the internal forces and dimensions of the main arch's arch foot. Since the anchor body arch seat mainly bears the internal forces of the main arch's arch foot, and the anchor body arch seat mainly relies on the embedded section 1 for force bearing, the internal forces of the main arch's arch foot can guide the depth L1 of the bedrock bearing layer across the unloading zone, the center height H3 of section C, the bottom width B3 of section C, the center height H4 of section D, the bottom width B4 of section D, and the radius R of the top arc of the anchor body arch seat's cross-section. The dimensions of the arch foot can guide the center height H1 and the bottom width B1 of section A. The combination of the internal forces and dimensions of the main arch's arch foot can guide the parameters of the anchor body arch seat. Furthermore, based on the foundation information at the anchor body arch seat, the unloading zone depth L2 can be obtained, and based on the unloading zone depth L2, the axial length of the force transmission section 2 can be obtained, which can guide the distance between sections B and C.

[0026] The bedrock bearing layer depth L1 across the unloading zone of the anchor body arch seat is used to calculate the constraint stiffness Ki of each rock layer within the unloading zone on the pile body according to the M method. In an optional implementation, in step S1, the depth of the bedrock bearing layer L1 of the unloading zone of the anchor body arch seat and the soil lateral resistance are used as the basis for the calculation. The constraint stiffness Ki of each rock layer within the unloading zone on the pile body is calculated according to the M method.

[0027] The M-method is a method used to calculate the horizontal displacement and action effect of elastic piles. It was first proposed by Matlock and Reese (1956), and the M-method is short for Matlock's method. In the M-method, M is the proportional coefficient of the horizontal resistance coefficient of the soil, which is the comprehensive value of all soil layers within a range of 2(d+1)m below the excavation surface of the foundation pit.

[0028] Furthermore, soil lateral resistance The foundation information at the anchorage arch was obtained from previous geological exploration.

[0029] S2. Based on the constraint stiffness Ki of each rock layer within the unloading zone on the pile body and the various parameters of the anchor body arch, establish a macroscopic finite element model of the anchor body arch considering the pile-soil effect. In an optional implementation, the macroscopic finite element model of the anchor block arch is established as follows: Based on the various parameters of the anchor body arch, a macroscopic rod element model of the anchor body arch reflecting the material and cross-sectional properties is established. Consolidation constraints are applied to the lower end of the anchor body arch in the macroscopic rod system element model of the anchor body arch; and constraint stiffness Ki of each rock layer within the unloading zone on the pile body is applied perpendicularly to the axis of the anchor body arch within the depth value L1 of the bedrock bearing layer across the unloading zone in the macroscopic rod system element model of the anchor body arch, so that the macroscopic finite element model of the anchor body arch fully considers the influence of the unloading zone on the stress state of the anchor body, and no longer considers the radial constraint effect of the foundation rock mass outside the unloading zone on the anchor body.

[0030] S3. Input the structural internal force load transmitted from the main arch to the anchor body arch seat. The macroscopic finite element model calculates the internal forces of sections A, B, C and D of the anchor body arch seat, as well as the axial force at the lower end of the anchor body arch seat embedded section 1. In an optional implementation, in step S3, the structural internal force load transmitted from the main arch to the anchor body arch seat includes axial force N, longitudinal bending moment My, transverse bending moment Mz, and shear force V. The axial force N, longitudinal bending moment My, transverse bending moment Mz, and shear force V are all determined based on the internal forces of the designed main arch foot and various parameters of the anchor body arch seat, which can more accurately simulate the actual stress situation of the anchor body arch seat.

[0031] Furthermore, since the shear force on the anchor body arch seat is mainly an in-plane shear force perpendicular to the axial force N and located on the arch elevation of the anchor body arch seat, the shear force V value is an in-plane shear force perpendicular to the axial force N and located on the arch elevation of the anchor body arch seat, which can reduce the complexity.

[0032] S4. Verify whether the bearing capacity of sections A, B, C, and D is greater than the internal forces of sections A, B, C, and D respectively. If at least one of the bearing capacities of sections A, B, C, and D is less than or equal to the corresponding internal forces of sections A, B, C, and D, then return to step S1 and increase the center height and bottom width of the corresponding section of the anchor body arch. For example, if the bearing capacity of section A is less than or equal to the internal force of section A, it means that the bearing capacity of section A does not meet the requirements, and the center height H1 and bottom width B1 of section A need to be increased. If the bearing capacity of section A is less than or equal to the internal force of section A, and the bearing capacity of section B is less than or equal to the internal force of section B, it means that the bearing capacities of sections A and B do not meet the requirements, and the center height H1 and bottom width B1 of section A need to be increased, while the center height H2 and bottom width B2 of section B need to be increased, and so on.

[0033] In an optional implementation, in step S4, the bearing capacity of sections A, B, C and D is calculated based on various parameters of the anchor body arch, mainly based on the center height, bottom width and reinforcement parameters of the sections. This calculation is mainly based on simple stress calculation of various parameters. The calculation method is based on the specifications and existing calculation formulas, which will not be described in detail in this embodiment.

[0034] Verification of foundation bearing capacity Whether it is greater than the axial force at the lower end of the anchor block arch seat embedded section 1, if the foundation bearing capacity If the axial force is less than or equal to the axial force at the lower end of the anchorage section 1, it represents the bearing capacity of the foundation. If the requirements are not met, return to step S1 and increase the bedrock bearing layer depth value L1 of the anchor block arch span unloading zone; in an optional implementation, in step S4, the foundation bearing capacity... The calculation formula is:

[0035] In the formula, The end drag utilization coefficient; Let D be the cross-sectional area; The standard value of the saturated uniaxial compressive strength of the rock at the lower end of the anchor body arch; The perimeter of the anchorage arch corresponding to each soil or rock layer within the unloading zone; The lateral resistance utilization coefficient of the i-th rock layer within the unloading zone; The thickness of each rock layer within the unloading zone of the anchor body arch; The standard value of the saturated uniaxial compressive strength of the rock in the i-th layer within the unloading zone is obtained based on the foundation information at the anchor body arch seat; i = 1, 2, ..., m; The coefficient for lateral resistance utilization of the overburden soil; Let be the thickness of the j-th soil layer. Let be the standard value of the lateral resistance of the j-th soil layer; j = 1, 2, ..., n. Foundation bearing capacity. The values ​​in the calculation formula are determined based on the foundation information, the "Design Specification for Foundations and Substructures of Highway Bridges and Culverts" JTG 3363-2019, and the geometric dimensions of the proposed anchor block arch.

[0036] After returning to step S1, repeat steps S2-S4 until: the bearing capacity of sections A, B, C, and D are all greater than the internal forces of sections A, B, C, and D, and the bearing capacity of the foundation is also greater. The axial force is greater than that at the lower end of the anchor block arch seat embedded section 1.

[0037] In an optional implementation, in step S4, the bearing capacity of the foundation is first verified. Whether it is greater than the axial force at the lower end of the anchor block arch seat embedded section 1, if the foundation bearing capacity If the axial force is less than or equal to the axial force at the lower end of the anchor-supported arch section 1, then return to step S1, increase the bedrock bearing layer depth L1 across the unloading zone of the anchor-support arch, and then repeat steps S2-S4 until the foundation bearing capacity is reached. Greater than the axial force at the lower end of the anchor block arch seat embedment section 1; If the bearing capacity of the foundation is greater than the axial force at the lower end of the anchor-type arch seat embedded section 1, then check whether the bearing capacity of sections A, B, C, and D is greater than the internal forces of sections A, B, C, and D. If at least one of the bearing capacities of sections A, B, C, and D is less than or equal to the corresponding internal forces of sections A, B, C, and D, then return to step S1 to increase the center height and bottom width of the corresponding sections of the anchor-type arch seat, and then repeat steps S2-S4 until the bearing capacity of sections A, B, C, and D is greater than the corresponding internal forces of sections A, B, C, and D.

[0038] This method of prioritizing the bearing capacity of the foundation The bearing capacity of sections A, B, C, and D was then verified, based on the foundation bearing capacity. If the requirements are not met, there is no need to verify the bearing capacity of sections A, B, C, and D, which reduces the workload of verification and improves the foundation bearing capacity. If the requirements are not met, a significant amount of verification resources can be saved.

[0039] In an optional implementation, after step S4, step S5 is further included: calculating the internal forces of section B of the anchorage arch under the self-weight load of only the anchorage arch using a macroscopic finite element model; configuring the prestressed steel strands 4 at the top of the anchorage arch based on the internal forces of section B under the self-weight load of only the anchorage arch; verifying whether the bearing capacity of section B of the anchorage arch meets the requirements; if not, reconfiguring the prestressed steel strands 4 until the requirements are met. By designing the prestressed steel strands 4 before the construction of the superstructure (main arch) of the arch bridge, the bearing capacity of the connecting section 3 of the anchorage arch is ensured, resulting in a safer structural stress distribution and a more rational design.

[0040] The design method of the anchor-plug arch seat described in this embodiment fully considers the influence of the unloading zone on the stress state of the anchor-plug arch seat, and no longer considers the radial constraint effect of the foundation rock mass outside the unloading zone on the anchor-plug arch seat. Before the construction of the superstructure of the arch bridge (such as the main arch), the bearing capacity of the connecting section 3 of the anchor-plug arch seat is guaranteed by designing prestress, making the structure safer and the design more reasonable.

[0041] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A design method for an anchor plug arch seat, characterized in that, The anchor body arch includes a fixed section (1), a force transmission section (2) and a connecting section (3) that are continuously arranged from the inside to the outside along the axial direction. The upper end face of the connecting section (3) is section A, the interface between the connecting section (3) and the force transmission section (2) is section B, the interface between the force transmission section (2) and the fixed section (1) is section C, and the lower end face of the fixed section (1) is section D. The design methodology includes the following steps: S1. Preliminary parameters of the anchor body arch, including the depth of the bedrock bearing layer across the unloading zone L1, the axial length L of the anchor body arch, the center height H1 of section A, the bottom width B1 of section A, the center height H2 of section B, the bottom width B2 of section B, the center height H3 of section C, the bottom width B3 of section C, the center height H4 of section D, the bottom width B4 of section D, and the radius R of the top arc of the cross-section of the anchor body arch. The bedrock bearing layer depth L1 across the unloading zone of the anchor body arch seat is used to calculate the constraint stiffness Ki of each rock layer within the unloading zone on the pile body according to the M method. S2. Based on the constraint stiffness Ki of each rock layer within the unloading zone on the pile body and the various parameters of the anchor body arch, establish a macroscopic finite element model of the anchor body arch considering the pile-soil effect. S3. Input the structural internal force load transmitted from the main arch to the anchor body arch seat. The macroscopic finite element model calculates the internal forces of the A, B, C and D sections of the anchor body arch seat and the axial force at the lower end of the anchor body arch seat embedded section (1). S4. Verify whether the bearing capacity of sections A, B, C, and D is greater than the internal forces of sections A, B, C, and D. If the bearing capacity of sections A, B, C, and D is less than or equal to the corresponding internal forces of sections A, B, C, and D, then return to step S1 to increase the center height and bottom width of the corresponding section of the anchor body arch. Verification of foundation bearing capacity Whether it is greater than the axial force at the lower end of the anchor block arch seat embedded section (1), if the foundation bearing capacity If the axial force is less than or equal to the lower end of the anchor body arch seat embedment section (1), then return to step S1 and increase the bedrock bearing layer depth value L1 of the anchor body arch seat across the unloading zone. After returning to step S1, repeat steps S2-S4 until: the bearing capacity of sections A, B, C, and D are all greater than the internal forces of sections A, B, C, and D, and the bearing capacity of the foundation is also greater. The axial force at the lower end of the anchor block arch seat embedment section (1) is greater than that of the anchor block.

2. The design method of an anchor plug arch seat according to claim 1, characterized in that, In step S1, the parameters of the anchor block arch seat are initially calculated based on the internal forces and dimensions of the arch foot of the main arch.

3. The design method of an anchor plug arch seat according to claim 1, characterized in that, In step S1, based on the bedrock bearing layer depth L1 of the anchor body arch span unloading zone and the soil lateral resistance... The constraint stiffness Ki of each rock layer within the unloading zone on the pile body is calculated according to the M method.

4. The design method of an anchor plug arch seat according to claim 3, characterized in that, Soil lateral resistance Obtained based on foundation information at the anchor body arch seat.

5. The design method of an anchor plug arch seat according to claim 1, characterized in that, The macroscopic finite element model of the anchor block arch is established as follows: Based on the various parameters of the anchor body arch, a macroscopic rod element model of the anchor body arch reflecting the material and cross-sectional properties is established. Consolidation constraints are applied to the lower end of the anchor body arch in the macro-bar system unit model of the anchor body arch; and constraint stiffness Ki of each rock layer within the unloading zone is applied perpendicularly to the axis of the anchor body arch within the bedrock bearing layer depth value L1 of the anchor body arch across the unloading zone in the macro-bar system unit model of the anchor body arch.

6. The design method of an anchor plug arch seat according to claim 1, characterized in that, In step S3, the structural internal force loads transmitted from the main arch to the anchor block arch seat include axial force N, longitudinal bending moment My, transverse bending moment Mz, and shear force V.

7. The design method of an anchor plug arch seat according to claim 6, characterized in that, The shear force V is an in-plane shear force perpendicular to the axial force N and located on the arch face of the anchor body arch seat.

8. The design method of an anchor plug arch seat according to claim 1, characterized in that, In step S4, the bearing capacity of sections A, B, C and D is calculated based on various parameters of the anchor body arch. Foundation bearing capacity The calculation formula is: In the formula, The end resistance utilization coefficient; Let D be the cross-sectional area; The standard value of the saturated uniaxial compressive strength of the rock at the lower end of the anchor body arch; The perimeter of the anchorage arch corresponding to each soil or rock layer within the unloading zone; The lateral resistance utilization coefficient of the i-th rock layer within the unloading zone; The thickness of each rock layer within the unloading zone of the anchor body arch; The standard value of the saturated uniaxial compressive strength of the rock in the i-th layer within the unloading zone is obtained based on the foundation information at the anchor body arch seat; i = 1, 2, ..., m; The coefficient for lateral resistance utilization of the overburden soil; Let be the thickness of the j-th soil layer. Let be the standard value of the lateral resistance of the j-th soil layer; j = 1, 2, ..., n.

9. The design method of an anchor plug arch seat according to claim 1, characterized in that, In step S4, the bearing capacity of the foundation is first verified. Whether it is greater than the axial force at the lower end of the anchor block arch seat embedded section (1), if the foundation bearing capacity If the axial force is less than or equal to the lower end of the anchor-bolt arch abutment embedment section (1), then return to step S1, increase the bedrock bearing layer depth L1 across the unloading zone of the anchor-bolt arch abutment, and then repeat steps S2-S4 until the foundation bearing capacity is reached. The axial force at the lower end of the anchor block arch seat embedment section (1) is greater than that of the anchor block. If the bearing capacity of the foundation is greater than the axial force at the lower end of the anchor-lock arch section (1), then check whether the bearing capacity of sections A, B, C and D is greater than the internal forces of sections A, B, C and D. If at least one of the bearing capacities of sections A, B, C and D is less than or equal to the corresponding internal forces of sections A, B, C and D, then return to step S1 to increase the center height and bottom width of the corresponding section of the anchor-lock arch, and then repeat steps S2-S4 until: the bearing capacity of sections A, B, C and D is greater than the corresponding internal forces of sections A, B, C and D.

10. The design method of an anchor plug arch seat according to claim 1, characterized in that, After step S4, step S5 is also included: calculating the internal force of section B of the anchor bolt arch when only the self-weight load of the anchor bolt arch is applied by the macroscopic finite element model of the anchor bolt arch; configuring the prestressed steel strand (4) at the top of the anchor bolt arch according to the internal force of section B of the anchor bolt arch when only the self-weight load of the anchor bolt arch is applied; verifying whether the bearing capacity of section B of the anchor bolt arch meets the requirements; if it does not meet the requirements, reconfiguring the prestressed steel strand (4) of the anchor bolt arch until the requirements are met.

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