Seismic ground motion input method, device and storage medium

Abstract

The present invention discloses a ground motion input method, device and storage medium. The method includes establishing a finite element model of the site considering the actual geological and topographical conditions, calculating the equivalent seismic load of the bottom boundary block, calculating the free-field ground motion time history of the one-dimensional corner column based on the equivalent seismic load of the bottom boundary block; calculating the equivalent seismic load of the one-dimensional corner column based on the free-field ground motion time history of the one-dimensional corner column; calculating the free-field ground motion time history of the side boundary block based on the equivalent seismic loads of the bottom boundary block and the one-dimensional corner column; calculating the equivalent seismic load of the side boundary block based on the free-field ground motion time history of the side boundary block; inputting the equivalent seismic loads of the bottom boundary block and the side boundary block into the finite element model of the site, and calculating the dynamic responses of the site and the engineering structure under the three-dimensional actual geological and topographical conditions. The present invention can simply and effectively realize the ground motion input at the site considering the actual geological and topographical effects.

Description

Technical Field

[0001] The present invention belongs to the technical field of geotechnical earthquake resistance, and particularly relates to a method, device and storage medium for earthquake ground motion input considering the geological and topographical effects of the site. Background Art

[0002] The geological and topographical conditions at the site have effects such as scattering and amplification on the propagation of seismic waves, which will significantly affect the regional earthquake ground motion propagation and structural dynamic response. When performing soil-structure dynamic calculations, this should be taken into account.

[0003] When considering the actual geological and topographical conditions of the site, how to input the earthquake ground motion into the calculation model becomes the first problem to be solved. In the existing earthquake ground motion input theories, usually the free wave field of the site is obtained by the analytical method first, and then the free wave field is converted into the equivalent load at the boundary to achieve the earthquake ground motion input. However, when considering the actual geological and topographical conditions of the site, the free wave field of the site cannot be directly obtained by the analytical method, so a new earthquake ground motion input method needs to be proposed.

[0004] Some scholars have done some research work on the earthquake ground motion input problem for two-dimensional irregular terrain sites, but there is still no relevant research on the earthquake ground motion input method considering the three-dimensional geological and topographical effects of the site and the structural dynamic response analysis.

[0005] For the above reasons, an earthquake ground motion input method considering the three-dimensional topographical effects of the site is proposed, which can provide an important reference for the earthquake propagation process and structural dynamic calculation and analysis of geotechnical engineering and hydraulic engineering. Summary of the Invention

[0006] The purpose of the present invention is to provide a method, device and storage medium for earthquake ground motion input to solve the problem that when considering the actual geological and topographical conditions of the site, the free wave field of the site cannot be directly obtained by the analytical method, and the earthquake ground motion input cannot be realized.

[0007] The present invention solves the above technical problems through the following technical solutions: An earthquake ground motion input method includes the following steps:

[0008] Construct a finite element model of the site considering the actual geological and topographical conditions, and extract the outermost layer of elements of the finite element model of the site as a dynamic calculation auxiliary model. The dynamic calculation auxiliary model includes a bottom boundary block, four side boundary blocks, and four one-dimensional corner columns; the one-dimensional corner columns are located between two adjacent side boundary blocks;

[0009] Calculate the equivalent seismic load of the bottom boundary block;

[0010] Based on the equivalent seismic load of the bottom boundary block, perform dynamic calculations on each of the one-dimensional corner columns to obtain the free-field earthquake ground motion time history of the one-dimensional corner columns;

[0011] Calculate the equivalent seismic load of the one-dimensional corner column based on the free-field ground motion time history of the one-dimensional corner column;

[0012] Based on the equivalent seismic loads of the bottom boundary block and the one-dimensional corner column, perform dynamic calculations on each of the side boundary blocks to obtain the free-field ground motion time history of the side boundary blocks;

[0013] Calculate the equivalent seismic load of the side boundary block based on the free-field ground motion time history of the side boundary block;

[0014] Input the equivalent seismic loads of the bottom boundary block and the side boundary blocks into the site finite element model to perform dynamic response analysis considering the geological and topographical conditions of the site.

[0015] Furthermore, the specific calculation process of the equivalent seismic load of the bottom boundary block is as follows:

[0016] Extract the bottom boundary block from the dynamic calculation auxiliary model, and apply viscous dampers to the out-of-plane outer nodes of the bottom boundary block; wherein, the out-of-plane outer nodes of the bottom boundary block refer to the nodes on the bottom surface of the bottom boundary block, the out-of-plane inner nodes of the bottom boundary block refer to the nodes on the top surface of the bottom boundary block, and the top surface of the bottom boundary block refers to the side facing the inside of the dynamic calculation auxiliary model;

[0017] Apply the incident ground motion time history to each node of the bottom boundary block, and then perform dynamic calculations on the bottom boundary block to obtain the reaction force time history of the out-of-plane outer nodes of the bottom boundary block, and the reaction force time history of the out-of-plane outer nodes of the bottom boundary block is the equivalent seismic load of the bottom boundary block.

[0018] Furthermore, the specific calculation formula for the equivalent seismic load of the bottom boundary block is:

[0019]

[0020] wherein, F bottom is the equivalent seismic load of the bottom boundary block; ρ is the medium density; C is the medium wave velocity, T is the node control area, and the node control area T of a certain node on the bottom boundary block is equal to the total area of the elements around the node divided by the number of elements; is the velocity time history of the incident wave field.

[0021] Furthermore, perform dynamic calculations on the one-dimensional corner column to obtain the free-field ground motion time history of the one-dimensional corner column, specifically including:

[0022] Extract four one-dimensional corner columns from the dynamic calculation auxiliary model, and apply viscous dampers to the bottommost layer nodes of each one-dimensional corner column;

[0023] For each one-dimensional corner column, apply the equivalent seismic load of the bottom boundary block to the nodes of the bottommost layer of the one-dimensional corner column, and then perform dynamic calculation on the one-dimensional corner column to obtain the numerical solution of the free-field ground motion time history of the one-dimensional corner column.

[0024] Furthermore, the specific calculation process of the equivalent seismic load of each one-dimensional corner column is as follows:

[0025] Extract four one-dimensional corner columns from the dynamic calculation auxiliary model, and apply viscous dampers to the outer nodes of each one-dimensional corner column;

[0026] Apply the free-field ground motion time history of the one-dimensional corner column to the one-dimensional corner column, and then perform dynamic calculation on the one-dimensional corner column to obtain the reaction force time history of the outer nodes of the one-dimensional corner column. The reaction force time history of the outer nodes of the one-dimensional corner column is the equivalent seismic load of the one-dimensional corner column.

[0027] Furthermore, perform dynamic calculation on the side boundary block to obtain the free-field ground motion time history of the side boundary block, specifically including:

[0028] Extract four side boundary blocks from the dynamic calculation auxiliary model, and apply viscous dampers to the in-plane side nodes and the bottom surface of each side boundary block; among them, the in-plane side nodes refer to the nodes in contact with the one-dimensional corner column;

[0029] For each side boundary block, apply the equivalent seismic load of the bottom boundary block and the equivalent seismic load of the one-dimensional corner column to the in-plane side nodes and the bottom surface of the side boundary block; apply periodic boundary constraints to the out-of-plane outer nodes and out-of-plane inner nodes of the side boundary block to simulate the plane strain condition of the side boundary block, where the periodic boundary constraint formula is:

[0030] {u A} = {u B}

[0031] where {u A} is the displacement vector of the out-of-plane outer node, and {u B} is the displacement vector of the out-of-plane inner node.

[0032] Perform dynamic calculation on the side boundary block to obtain the free-field ground motion time history of the side boundary block.

[0033] Furthermore, the specific calculation process of calculating the equivalent seismic load of the side boundary block is as follows:

[0034] Extract four side boundary blocks from the dynamic calculation auxiliary model, and apply viscous dampers to the out-of-plane outer nodes of each side boundary block;

[0035] Apply the free-field ground motion time history of the side boundary block to the side boundary block, and then perform dynamic calculation on the side boundary block to obtain the reaction force time history of the out-of-plane outer nodes of the side boundary block. The reaction force time history of the out-of-plane outer nodes of the side boundary block is the equivalent seismic load of the side boundary block.

[0036] Furthermore, the specific calculation formula for the equivalent seismic load of the side boundary block is:

[0037]

[0038] where F side is the equivalent seismic load of the side boundary block, A is the out-of-plane outer node, B is the out-of-plane inner node, [M], [C], and [K] are the mass matrix, damping matrix, and stiffness matrix respectively; is the sub-block of the mass matrix [M] with rows and columns corresponding to nodes A and B respectively; is the free-field acceleration time history of node B, is the sub-block of the mass matrix [M] with both rows and columns corresponding to node A, is the free-field acceleration time history of node A, is the sub-block of the damping matrix [C] with rows and columns corresponding to nodes A and B respectively; is the free-field velocity time history of node B, is the sub-block of the damping matrix [C] with both rows and columns corresponding to node A, is the free-field velocity time history of node A, is the sub-block of the stiffness matrix [K] with rows and columns corresponding to nodes A and B respectively, is the free-field displacement time history of node B, is the sub-block of the stiffness matrix [K] with both rows and columns corresponding to node A, is the free-field displacement time history of node A.

[0039] Furthermore, the calculation formula for the damping coefficient of the viscous damper is:

[0040]

[0041]

[0042] where C BT is the damping coefficient of the tangential damper, C BN is the damping coefficient of the normal damper, ρ is the medium density, C P is the longitudinal wave velocity of the medium, C s is the shear wave velocity of the medium, λ and G are the Lame constants of the medium, E is the elastic modulus of the medium, and ν is the Poisson's ratio.

[0043] Based on the same inventive concept, the present invention further provides an electronic device, which includes:

[0044] A memory for storing a computer program;

[0045] A processor for implementing the steps of the above-mentioned ground motion input method when executing the computer program.

[0046] Based on the same inventive concept, the present invention further provides a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the steps of the above-mentioned ground motion input method are implemented.

[0047] Advantageous Effects

[0048] Compared with the prior art, the advantages of the present invention are as follows:

[0049] The present invention establishes a dynamic calculation auxiliary boundary for the site finite element model considering the actual geological and topographical conditions, calculates the equivalent seismic load of the bottom boundary block, calculates the free-field ground motion time history of the one-dimensional corner column based on the equivalent seismic load of the bottom boundary block; calculates the equivalent seismic load of the one-dimensional corner column based on the free-field ground motion time history of the one-dimensional corner column; calculates the free-field ground motion time history of the side boundary block based on the equivalent seismic load of the bottom boundary block and the one-dimensional corner column; calculates the equivalent seismic load of the side boundary block based on the free-field ground motion time history of the side boundary block; inputs the equivalent seismic loads of the bottom boundary block and the side boundary block into the site finite element model, and uses the finite element method to calculate the dynamic response of the site and the engineering structure under the three-dimensional actual geological and topographical conditions. The present invention can simply and effectively realize the ground motion input at the site considering the actual geological and topographical effects.

[0050] The dynamic calculations of each step of the present invention can be realized with the aid of commercial software, without complex programming and are easy to implement. Description of the Drawings

[0051] In order to more clearly illustrate the technical solutions of the present invention, the drawings required for the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only one embodiment of the present invention, and those of ordinary skill in the art can obtain other drawings based on these drawings without creative efforts.

[0052] Figure 1 is the flow chart of the ground motion input method in the embodiment of the present invention;

[0053] Figure 2 is the dynamic calculation auxiliary model in the embodiment of the present invention.

[0054] Among them, 1 - bottom boundary block, 2 - side boundary block, 21 - nodes on the outer side of the side boundary block (i.e., out - of - plane outer nodes), 22 - nodes on the inner side of the side boundary block (i.e., out - of - plane inner nodes), 23 - in - plane inner nodes of the side boundary block, 3 - one - dimensional corner column, 31 - inner nodes of the one - dimensional corner column, 32 - outer nodes of the one - dimensional corner column. Detailed implementation manners

[0055] Combined with the accompanying drawings in the embodiments of the present invention, the technical solutions in the present invention are described clearly and completely. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the present invention.

[0056] The technical solutions of the present application will be described in detail with specific embodiments below. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments.

[0057] As Figure 1 shown, a ground motion input method provided in this embodiment includes the following steps:

[0058] Step 1: Construct a finite - element model of the site considering the actual geological and topographical conditions, and extract the outermost layer of elements of the finite - element model of the site as a dynamic calculation auxiliary model.

[0059] In this embodiment, a finite - element model of the site considering the actual geological and topographical conditions is constructed by using the finite - element analysis software ANSYS, and the outermost layer of elements is extracted from the finite - element model of the site as a dynamic calculation auxiliary model. The outermost layer of elements includes two layers of nodes.

[0060] Figure 2The schematic diagram of the dynamic calculation auxiliary model is shown. The dynamic calculation auxiliary model includes a bottom boundary block 1, four side boundary blocks 2, and four one-dimensional corner columns 3; the one-dimensional corner columns 3 are located between two adjacent side boundary blocks 2. For the convenience of subsequent description, the node sets are defined here: (1) According to the normal direction of each boundary block, the bottom boundary block 1 and the side boundary blocks 2 are divided into two layers of nodes, namely the out-of-plane outer nodes (such as the node 21 on the outer side of the side boundary block) and the out-of-plane inner nodes (such as the node 22 on the inner side of the side boundary block), and the inner side refers to the side facing the inside of the dynamic calculation auxiliary model; (2) In the plane of each side boundary block 2, the nodes in contact with the one-dimensional corner column block 3 are defined as the in-plane inner side nodes 23; (3) For the one-dimensional corner column 3, according to the relative relationship between the one-dimensional corner column and the two-dimensional side boundary block, the one-dimensional corner column inner nodes (such as the inner node 31 on the one-dimensional corner column, that is, the node in contact with the side boundary block 2) and the one-dimensional corner column outer nodes (such as the outer node 32 on the one-dimensional corner column) are defined.

[0061] Step 2: Calculate the equivalent seismic load of the bottom boundary block 1.

[0062] In this embodiment, there are two calculation methods for the equivalent seismic load of the bottom boundary block 1. The specific calculation process of one of them is as follows:

[0063] Step 2.1: Extract the bottom boundary block 1 from the dynamic calculation auxiliary model, and apply viscous dampers to the out-of-plane outer nodes of the bottom boundary block 1;

[0064] Step 2.2: Apply the incident seismic ground motion time history to each node of the bottom boundary block 1, and then perform dynamic calculation on the bottom boundary block 1 to obtain the reaction force time history of the out-of-plane outer nodes of the bottom boundary block 1. The reaction force time history of the out-of-plane outer nodes of the bottom boundary block 1 is the equivalent seismic load of the bottom boundary block 1.

[0065] In Step 2.1, the radiation damping effect of the infinite foundation is simulated by using viscous dampers. The calculation formula for the damping coefficient of the viscous damper is:

[0066]

[0067]

[0068] Among them, C BT is the damping coefficient of the tangential damper, C BN is the damping coefficient of the normal damper, ρ is the medium density (such as the foundation density), C P is the longitudinal wave velocity of the medium, C s is the shear wave velocity of the medium, λ and G are both Lame constants of the medium, E is the elastic modulus of the medium, and ν is the Poisson's ratio.

[0069] According to the wave field separation theory, another calculation method for the equivalent seismic load of the bottom boundary block 1 is as follows:

[0070]

[0071] Where F bottom is the equivalent seismic load of the bottom boundary block 1; ρ is the medium density; C is the medium wave velocity, T is the node control area (also called the node influence area), and the node control area T of a certain node on the bottom boundary block is equal to the total area of the elements around the node divided by the number of elements; is the velocity time history of the incident wave field. The medium wave velocity C is an inherent property of the foundation. When calculating the equivalent seismic loads in different directions of the bottom boundary block 1, the medium wave velocity C and the velocity time history of the incident wave field take the corresponding values in the corresponding directions. Exemplarily, taking the direction perpendicular to the bottom boundary block 1 as the Z-axis and the plane where the bottom boundary block is located as the XY plane, when calculating the equivalent seismic load of the bottom boundary block 1 in the Z direction, the medium wave velocity C is taken as the longitudinal wave velocity C P of the medium, and the velocity time history of the incident wave field is the velocity time history of the incident wave field in the Z direction When calculating the equivalent seismic load of the bottom boundary block 1 in the X or Y direction, the medium wave velocity C is the shear wave velocity C s of the medium, and the velocity time history of the incident wave field is the velocity time history of the incident wave field in the X or Y direction or

[0072] Since the finite element model of the site is usually relatively complex, it is rather cumbersome to directly calculate the equivalent seismic load of the bottom boundary block 1 using the theoretical formula (3); adopting the dynamic calculation method in steps 2.1 - 2.2 to calculate the equivalent seismic load of the bottom boundary block 1, the dynamic calculation can be completed in a general finite element software, and the calculation process is more convenient, reducing the calculation difficulty.

[0073] Step 3: Based on the equivalent seismic load of the bottom boundary block 1, perform dynamic calculations on each one-dimensional corner column 3 to obtain the free-field ground motion time history of the one-dimensional corner column 3.

[0074] In this embodiment, performing dynamic calculations on the one-dimensional corner column 3 to obtain the free-field ground motion time history of the one-dimensional corner column 3 specifically includes:

[0075] Step 3.1: Extract four one-dimensional corner columns 3 from the dynamic calculation auxiliary model, and apply viscous dampers to the nodes of the bottommost layer of each one-dimensional corner column 3. The calculation formula for the damping coefficient of the viscous damper is shown in formulas (1) and (2);

[0076] Step 3.2: For each one-dimensional corner column 3, apply the equivalent seismic load of the bottom boundary block 1 to the nodes of the bottommost layer of the one-dimensional corner column 3, and then perform dynamic calculation on the one-dimensional corner column 3 to obtain the numerical solution of the free-field ground motion time history of this one-dimensional corner column 3.

[0077] The free-field ground motion time history of the one-dimensional corner column 3 includes velocity, acceleration, and displacement time histories.

[0078] Step 4: Based on the free-field ground motion time history of the one-dimensional corner column 3, calculate the equivalent seismic load of the one-dimensional corner column 3.

[0079] In this embodiment, the specific calculation process of the equivalent seismic load of each one-dimensional corner column 3 is as follows:

[0080] Step 4.1: Extract the four one-dimensional corner columns 3 from the dynamic calculation auxiliary model, and apply viscous dampers to the outer nodes 32 of each one-dimensional corner column 3. The calculation formula for the damping coefficient of the viscous damper is shown in Formulas (1) and (2);

[0081] Step 4.2: Apply the free-field ground motion time history of this one-dimensional corner column 3 to the one-dimensional corner column 3, and then perform dynamic calculation on this one-dimensional corner column 3 to obtain the reaction force time history of the outer nodes 32 of this one-dimensional corner column 3. The reaction force time history of the outer nodes 32 of the one-dimensional corner column 3 is the equivalent seismic load of the one-dimensional corner column 3.

[0082] Step 5: Based on the equivalent seismic loads of the bottom boundary block 1 and the one-dimensional corner column 3, perform dynamic calculation on each side boundary block 2 to obtain the free-field ground motion time history of the side boundary block 2.

[0083] In this embodiment, performing dynamic calculation on the side boundary block 2 to obtain the free-field ground motion time history of the side boundary block 2 specifically includes:

[0084] Step 5.1: Extract the four side boundary blocks 2 from the dynamic calculation auxiliary model, and apply viscous dampers to the in-plane side nodes 23 and the bottom surface of each side boundary block. The calculation formula for the damping coefficient of the viscous damper is shown in Formulas (1) and (2).

[0085] Step 5.2: For each side boundary block 2, apply the equivalent seismic load of the bottom boundary block 1 and the equivalent seismic load of the one-dimensional corner column 3 to the in-plane side nodes 23 and the bottom surface of the side boundary block 2; apply periodic boundary constraints to the out-of-plane outer nodes 21 and out-of-plane inner nodes 22 of the side boundary block to simulate the plane strain condition of the side boundary block 2, where the periodic boundary constraint formula is:

[0086] {u A}={u B} (4)

[0087] where, {uA} is the displacement vector of the nodes outside the plane, {u B} is the displacement vector of the nodes inside the plane.

[0088] Step 5.3: Perform dynamic calculation on the side boundary block 2 to obtain the free-field ground motion time history of the side boundary block 2.

[0089] Step 6: Based on the free-field ground motion time history of the side boundary block 2, calculate the equivalent seismic load of the side boundary block 2.

[0090] In this embodiment, there are two calculation methods for the equivalent seismic load of the side boundary block 2. The specific calculation process of one of them is as follows:

[0091] Step 6.1: Extract four side boundary blocks 2 from the dynamic calculation auxiliary model, and apply viscous dampers to the nodes 21 outside the plane of each side boundary block. The calculation formula for the damping coefficient of the viscous damper is shown in Eqs. (1) and (2);

[0092] Step 6.2: Apply the free-field ground motion time history of the side boundary block 2 to the side boundary block 2, and then perform dynamic calculation on the side boundary block 2 to obtain the reaction force time history of the nodes 21 outside the plane of the side boundary block. The reaction force time history of the nodes 21 outside the plane of the side boundary block is the equivalent seismic load of the side boundary block 2.

[0093] According to the node division in the dynamic calculation auxiliary model, another calculation method for the equivalent seismic load of the side boundary block 2 is:

[0094]

[0095] Among them, F side is the equivalent seismic load of the side boundary block, A is the node outside the plane, B is the node inside the plane, [M], [C], and [K] are the mass matrix, damping matrix, and stiffness matrix respectively; is the sub-block of the mass matrix [M] with rows and columns being nodes A and B respectively; is the free-field acceleration time history of node B, is the sub-block of the mass matrix [M] with both rows and columns being node A, is the free-field acceleration time history of node A, is the sub-block of the damping matrix [C] with rows and columns being nodes A and B respectively; is the free-field velocity time history of node B, is the sub-block of the damping matrix [C] with both rows and columns being node A, is the free-field velocity time history of node A, is the sub-block of the stiffness matrix [K] with rows and columns being nodes A and B respectively, is the free-field displacement time history of Node B, is the sub-block in the stiffness matrix [K] where both the row and column are related to Node A, is the free-field displacement time history of Node A.

[0096] Step 7: Input the equivalent seismic loads of the bottom boundary block 1 and the side boundary block 2 into the finite element model of the site, and then the dynamic response analysis considering the geological and topographical conditions of the site can be carried out to calculate the dynamic responses of the site and the engineering structure under the three-dimensional real topographical conditions.

[0097] An embodiment of the present invention also provides an electronic device, which includes: a processor and a memory storing a computer program, and the processor is configured to implement the steps of the above-mentioned ground motion input method when executing the computer program.

[0098] Although not shown, the electronic device includes a processor, which can perform various appropriate operations and processes according to the programs and / or data stored in the read-only memory (ROM) and / or the programs and / or data loaded from the storage part into the random access memory (RAM). The processor can be a multi-core processor or include multiple processors. In some embodiments, the processor can include a general main processor and one or more special coprocessors, such as a central processing unit, a graphics processing unit (GPU), a neural network processing unit (NPU), a digital signal processing unit (DSP), and so on. In the RAM, various programs and data required for the operation of the electronic device are also stored. The processor, ROM, and RAM are connected to each other through a bus. The input / output (I / O) interface is also connected to the bus.

[0099] The above-mentioned processor and the memory are jointly used to execute the program stored in the memory, and when the program is executed by a computer, it can implement the methods, steps, or functions described in the above embodiments.

[0100] Although not shown, an embodiment of the present invention also provides a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, it implements the steps of the above-mentioned ground motion input method.

[0101] The storage medium in an embodiment of the present invention includes permanent and non-permanent, removable and non-removable articles that can implement information storage by any method or technology. Examples of 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, compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical storage, magnetic cassette tapes, magnetic disk storage or other magnetic storage devices, or any other non-transitory medium that can be used to store information accessible by a computing device.

[0102] The above-disclosed are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention can easily think of changes or variations, which should all be covered within the protection scope of the present invention.

Claims

1. A ground motion input method, characterized in that It includes the following steps: Construct a finite element model of the site considering the actual geological and topographical conditions, and extract the outermost layer of elements of the finite element model of the site as a dynamic calculation auxiliary model. The dynamic calculation auxiliary model includes a bottom boundary block, four side boundary blocks, and four one-dimensional corner columns; the one-dimensional corner columns are located between two adjacent side boundary blocks; Calculate the equivalent seismic load of the bottom boundary block; Based on the equivalent seismic load of the bottom boundary block, perform dynamic calculations on each of the one-dimensional corner columns to obtain the free-field ground motion time history of the one-dimensional corner columns; Based on the free-field ground motion time history of the one-dimensional corner columns, calculate the equivalent seismic load of the one-dimensional corner columns; Based on the equivalent seismic loads of the bottom boundary block and the one-dimensional corner columns, perform dynamic calculations on each of the side boundary blocks to obtain the free-field ground motion time history of the side boundary blocks; Based on the free-field ground motion time history of the side boundary blocks, calculate the equivalent seismic load of the side boundary blocks; Input the equivalent seismic loads of the bottom boundary block and the side boundary blocks into the finite element model of the site to perform dynamic response analysis considering the geological and topographical conditions of the site.

2. The earthquake ground motion input method according to claim 1, wherein The specific calculation process of the equivalent seismic load of the bottom boundary block is as follows: Extract the bottom boundary block from the dynamic calculation auxiliary model, and apply viscous dampers to the out-of-plane outer nodes of the bottom boundary block; wherein, the out-of-plane outer nodes of the bottom boundary block refer to the nodes on the bottom surface of the bottom boundary block, the out-of-plane inner nodes of the bottom boundary block refer to the nodes on the top surface of the bottom boundary block, and the top surface of the bottom boundary block refers to the side facing the inside of the dynamic calculation auxiliary model; Apply the incident ground motion time history to each node of the bottom boundary block, and then perform dynamic calculations on the bottom boundary block to obtain the reaction force time history of the out-of-plane outer nodes of the bottom boundary block. The reaction force time history of the out-of-plane outer nodes of the bottom boundary block is the equivalent seismic load of the bottom boundary block.

3. The ground motion input method according to claim 1, wherein The specific calculation formula for the equivalent seismic load of the bottom boundary block is: Among them, F bottom is the equivalent seismic load of the bottom boundary block; ρ is the medium density; C is the medium wave velocity, T is the node control area, and the node control area T of a certain node on the bottom boundary block is equal to the total area of the elements around the node divided by the number of elements; is the velocity time history of the incident wave field.

4. The ground motion input method according to claim 1, wherein Performing dynamic calculations on the one-dimensional corner columns to obtain the free-field ground motion time history of the one-dimensional corner columns specifically includes: Extract the four one-dimensional corner columns from the dynamic calculation auxiliary model, and apply viscous dampers to the nodes of the bottommost layer of each one-dimensional corner column; For each one-dimensional corner column, apply the equivalent seismic load of the bottom boundary block to the nodes of the bottommost layer of the one-dimensional corner column, and then perform dynamic calculations on the one-dimensional corner column to obtain the numerical solution of the free-field ground motion time history of the one-dimensional corner column.

5. The ground motion input method according to claim 1, characterized in that, The specific calculation process of the equivalent seismic load of each one-dimensional corner column is as follows: Extract the four one-dimensional corner columns from the dynamic calculation auxiliary model, and apply viscous dampers to the outer nodes of each one-dimensional corner column; Apply the free-field ground motion time history of the one-dimensional corner column to the one-dimensional corner column, and then perform dynamic calculations on the one-dimensional corner column to obtain the reaction force time history of the outer nodes of the one-dimensional corner column. The reaction force time history of the outer nodes of the one-dimensional corner column is the equivalent seismic load of the one-dimensional corner column.

6. The ground motion input method according to claim 1, wherein Performing dynamic calculations on the side boundary blocks to obtain the free-field ground motion time history of the side boundary blocks specifically includes: Extract four side boundary blocks from the dynamic calculation auxiliary model, and apply viscous dampers to the in-plane side nodes and the bottom surface of each side boundary block; wherein, the in-plane side nodes refer to the nodes in contact with the one-dimensional corner columns. For each side boundary block, apply the equivalent seismic load of the bottom boundary block and the equivalent seismic load of the one-dimensional corner column to the in-plane side nodes and the bottom surface of the side boundary block; apply periodic boundary constraints to the out-of-plane outer nodes and the out-of-plane inner nodes of the side boundary block to simulate the plane strain conditions of the side boundary block, where the periodic boundary constraint formula is: {u A} = {u B} where {u A} is the displacement vector of the nodes outside the out-of-plane, and {u B} is the displacement vector of the nodes inside the out-of-plane; Perform dynamic calculation on the side boundary block to obtain the free-field ground motion time history of the side boundary block.

7. The ground motion input method according to claim 1, wherein The specific calculation process for calculating the equivalent seismic load of the side boundary block is as follows: Extract four side boundary blocks from the dynamic calculation auxiliary model, and apply viscous dampers to the out-of-plane outer nodes of each side boundary block. Apply the free-field ground motion time history of the side boundary block to the side boundary block, and then perform dynamic calculation on the side boundary block to obtain the reaction force time history of the out-of-plane outer nodes of the side boundary block. The reaction force time history of the out-of-plane outer nodes of the side boundary block is the equivalent seismic load of the side boundary block.

8. The ground motion input method according to any one of claims 2, 4 to 7, characterized in that, The calculation formula for the damping coefficient of the viscous damper is: Among them, C BT is the damping coefficient of the tangential damper, C BN is the damping coefficient of the normal damper, ρ is the medium density, C P is the longitudinal wave velocity of the medium, C s is the shear wave velocity of the medium, λ and G are both Lame constants of the medium, E is the elastic modulus of the medium, and ν is the Poisson's ratio.

9. An electronic device, characterized in that, The device includes: A memory for storing a computer program; A processor for implementing the steps of the ground motion input method according to any one of claims 1 to 8 when executing the computer program.

10. A computer-readable storage medium, characterized in that, A computer program is stored on the computer-readable storage medium, and when the computer program is executed by the processor, the steps of the ground motion input method according to any one of claims 1 to 8 are implemented.

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