A method for adjusting ground motion parameters for non-uniform sites across different site types in mountainous areas

Abstract

The present invention relates to the field of site seismic motion, and discloses a method for adjusting seismic motion parameters of non-uniform sites across different site categories in mountainous areas, including determining the relationship between the structure and the site position and the boundary range of the structure; determining the rock and soil parameters of the underlying soil layer and the site category to which each position of the structure belongs; establishing a free field model of a non-uniform site of inclined bedrock and an overall finite element model considering soil-structure interaction, and at the same time establishing a flat bedrock finite element model corresponding to different site categories for comparison; then performing a dynamic time history analysis on the above models; and obtaining a method for adjusting seismic motion parameters of a non-uniform site of inclined bedrock according to the analysis results. This scheme takes into account the influence of factors such as the proportion of different site categories, bedrock inclination, soil layer thickness, and structural base width, and provides a method for adjusting the seismic response of the structure through numerical simulation calculation and analysis. Compared with the seismic response calculation and structural design based on the most unfavorable soil cover, this method is more economical.

Description

Technical Field

[0001] The invention relates to the technical field of site seismic motion, and in particular to a method for adjusting parameters of non-uniform site seismic motion across different site categories in mountainous areas. Background Art

[0002] For different site categories, the Code for Seismic Design of Buildings GB50011-2010 (2016 edition) divides site conditions into four categories: I, II, III, and IV according to the equivalent shear wave velocity of the soil layer and the thickness of the site cover layer. Category I is divided into two subcategories: I0 and I1, as shown in Table 1.

[0003] Table 1 Classification method of anti-corrosion site

[0004]

[0005] Note: The table shows the shear wave velocity of vs rock

[0006] In the field of structural engineering, earthquake zones are divided into different earthquake groups based on earthquake risk and earthquake probability, so that the impact of earthquake loads can be considered when designing buildings or other structures. If the design earthquake group remains unchanged, the eigenvalue of the design response spectrum will increase as the site becomes weaker. That is, when the same structure is seismically designed with reference to the design response spectrum, the weaker the site conditions of the structure, the greater the earthquake effect it will receive. However, in actual engineering, Figure 1 As shown in the figure, on a site with inclined bedrock, excavation and filling to obtain a flat surface may result in different thicknesses of the covering layer corresponding to the ground where the structure is located, resulting in the base of the structure corresponding to different site categories. In view of the impact of local crossing of multiple site categories on the seismic response of the structure in this special case, in actual engineering, if the structure crosses different site categories, the geological survey unit and the design unit generally consider the seismic action based on the most unfavorable site category (i.e., the higher category site category). For example: if the structure has both Class I and Class II, the Class II site is used for design; if the structure crosses Class II and Class III sites at the same time, the Class III site is used for design.

[0007] At present, there are few studies on the laws of structural seismic response when the structure is located in different site categories, and there is no suitable calculation and design method for the structural seismic response under this special site category. In actual engineering, the seismic response calculation and structural design are carried out based on the most unfavorable soil cover, which is a relatively poor economic method. Summary of the invention

[0008] The present invention aims to provide a method for adjusting non-uniform site seismic parameters across different site categories in mountainous areas, so as to solve the problem that there is no better structural seismic response calculation method when the structure is located in different site categories in inclined bedrock, and the economic efficiency of seismic response calculation and structural design is relatively poor.

[0009] To achieve the above object, the present invention provides the following technical solution: a method for adjusting ground motion parameters of non-uniform sites across different site categories in mountainous areas, comprising the following steps:

[0010] Step 1: Determine the relationship between the structure and the site and the structural boundary range;

[0011] Step 2: Determine the soil type, thickness of each soil layer and corresponding geotechnical characteristic parameters under the structure;

[0012] Step 3: Conduct a shear wave velocity experiment to obtain the shear wave velocity corresponding to each soil layer;

[0013] Step 4: Determine the site category of each location of the structure based on the thickness of each soil layer and the corresponding shear wave velocity in steps 2 and 3;

[0014] Step 5: Based on the position, thickness and geotechnical parameters of each soil layer obtained in step 2, multiple free field models of inclined bedrock non-uniform sites and an overall finite element model (SSI model for short) considering soil-structure interaction are established by considering factors such as different site category proportions, bedrock inclination, soil layer thickness, and structural base width;

[0015] Step 6: According to the inclined bedrock model in step 5, a flat bedrock free field model and a flat bedrock SSI model corresponding to different site categories (thin soil side and thick soil side of inclined bedrock) are established;

[0016] Step 7: Select the actual recorded bedrock ground motion to be vertically incident at the bottom of all models (the inclined bedrock non-uniform site free field model and SSI model in step 5 and the flat bedrock free field model and flat bedrock SSI model in step 6) for dynamic time history analysis;

[0017] Step 8: Draw the average value diagram of surface earthquake acceleration response spectrum at the corresponding position of the vertical components at the bottom of the structure in the inclined bedrock free field model and the flat bedrock free field model, the structural base shear force diagram and the average value diagram of maximum layer displacement of the inclined bedrock SSI model and the flat bedrock SSI model obtained in step 7;

[0018] Step 9: Based on the average value diagram of the surface earthquake acceleration response spectrum of the flat bedrock free field model on the thick soil side and the thin soil side in step 8 and the response spectrum value obtained in step 7, the intersection of the site surface response spectrum of the flat bedrock model corresponding to the thick soil side and the thin soil side is used as the boundary to divide: 0-C seconds segment is a relatively high frequency segment, C-6 seconds is a relatively low frequency segment, where C is the intersection of the response spectrum;

[0019] Step 10: Integrate the response spectrum obtained in step 8 and the relatively low-frequency segment divided in step 9 to obtain parameter γ, where γ represents the difference between the average value of the surface seismic response spectrum of the inhomogeneous site and the seismic response of the corresponding flat bedrock site, where Where f(T) is the surface response spectrum value of the inclined bedrock model at the value point x; F thin (T) is the surface response spectrum value of the flat bedrock free field corresponding to the thin soil side; F thick (T) is the surface response spectrum value of the flat bedrock free field corresponding to the thick soil side;

[0020] Step 11: Obtain the structural base shear force and maximum layer displacement in the inclined bedrock SSI model and the corresponding flat bedrock SSI model according to step 7, and use the constructed parameter γ v and γ D They respectively characterize the closeness between the seismic response of the inclined bedrock SSI model structure and the seismic response of the corresponding flat bedrock site, where

[0021] Among them, Δ D is the average value of the maximum interlayer displacement angle of the inclined bedrock SSI model structure under the action of each seismic wave, Δ Dh1 is the average value of the maximum interlayer displacement angle of the flat bedrock SSI model structure corresponding to the thin soil side site category under the action of each seismic wave, Δ Dh2 is the average value of the maximum interlayer displacement angle of the flat bedrock SSI model structure corresponding to the thick soil side site category under the action of each seismic wave, V is the average base shear force of the inclined bedrock SSI model structure, V h1 is the average shear force of the flat bedrock SSI model structure corresponding to the thin soil side site category, V h2 is the average shear force of the base of the SSI model structure on flat bedrock corresponding to the thick soil side site category;

[0022] Step 12: According to step 10 and step 11, get γ and γ V and γ D The values ​​are all less than or equal to 1+β, where β is the proportion of the structure on the thick soil side. When there are two types of site categories, β = site area of ​​the higher site category / total site area;

[0023] Step 13: Based on the statistical results of step 12, the seismic response of the structure on the inclined bedrock non-uniform site can be interpolated according to the proportion of the structure in the thick soil side β and the structural seismic response of the corresponding site category, so as to guide the calculation of seismic actions and seismic verification of structures located across different site categories. The seismic motion parameter adjustment formula is: seismic influence coefficient of the structure on the inclined bedrock non-uniform site = β*(seismic influence coefficient calculated for the higher site category - seismic influence coefficient calculated for the lower site category) + seismic influence coefficient calculated for the lower category.

[0024] Preferably, in step 7, at least 7 groups of actual recorded bedrock earthquake motions are selected to be vertically incident on the bottom of the model for dynamic time history analysis.

[0025] Preferably, the geotechnical characteristic parameters in step 2 include: soil density, cohesion, elastic modulus, shear modulus, friction angle and Poisson's ratio.

[0026] Preferably, in step 10 and step 11, γ and γ V and γ D The value is obtained by calculating the integral of the response spectrum based on the C-6 second period segment. Its value is between 1 and 2, representing the degree of difference between the surface seismic motion parameters of the inclined bedrock site and the corresponding flat bedrock site. The closer the value is to 1, the closer its seismic response is to the corresponding seismic response of the thin soil side site category; the closer the value is to 2, the closer its seismic response is to the corresponding seismic response of the thick soil side site category.

[0027] Preferably, when there are Class I and Class II sites in steps 12 and 13, β=Class II site area / total site area; the seismic influence coefficient of the structure on the inclined bedrock non-uniform site=β*(seismic influence coefficient calculated for Class II site category-seismic influence coefficient calculated for Class I site category)+seismic influence coefficient calculated for Class I site category.

[0028] Preferably, when there are Class II and Class III sites in step 12 and step 13, β=Class III site area / total site area, and the structural seismic response is calculated by interpolation based on the site category proportion β; the structural seismic influence coefficient on the inclined bedrock non-uniform site=β*(seismic influence coefficient calculated for Class III site category-seismic influence coefficient calculated for Class II site category)+seismic influence coefficient calculated for Class II site category.

[0029] Preferably, in step 5 and step 6, a fixed boundary is used at the bottom of all finite element models, and a distance of 15 times the maximum soil thickness in the model outside the structural range is taken on both sides as an approximate infinite boundary.

[0030] This scheme takes into account the influence of factors such as the proportion of different site categories, bedrock inclination, soil thickness, structural base width, etc., and provides an adjustment method for the structural seismic response through numerical simulation calculation and analysis, and simplifies it into an interpolation processing of seismic effects according to the site proportion. Compared with seismic response calculation and structural design based on the most unfavorable soil cover condition, the method of the present invention is more economical; compared with establishing a finite element model for calculation, this method is much more convenient and more conducive to practical engineering applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is a schematic diagram of an embodiment of the present invention in which the structure is located in both Class I and Class II sites.

[0032] Figure 2 Schematic diagram of a flow chart of an embodiment of the present invention.

[0033] Figure 3 This is a schematic diagram of a free field model of an inclined bedrock site according to an embodiment of the present invention.

[0034] Figure 4 This is a schematic diagram of the inclined bedrock SSI model according to an embodiment of the present invention.

[0035] Figure 5 Schematic diagram of a flat bedrock finite element model according to an embodiment of the present invention.

[0036] Figure 6 Schematic diagram of C value points of the present invention.

[0037] Figure 7 1 is a partial free-field model earthquake acceleration response spectrum diagram of an embodiment of the present invention.

[0038] Figure 8 1 is a partial free-field model earthquake acceleration response spectrum diagram of an embodiment of the present invention.

[0039] Fig. 9 1 is a partial free-field model earthquake acceleration response spectrum diagram of an embodiment of the present invention.

[0040] Fig.10 1 is a partial free-field model earthquake acceleration response spectrum diagram of an embodiment of the present invention.

[0041] Fig.11 It is a diagram showing the increase of the base shear force of the embodiment of the present invention relative to h1 corresponding to the SSI model of flat bedrock.

[0042] Fig.12 This is the SSI model increase diagram of the maximum interlayer displacement relative to h1 corresponding to the flat bedrock in an embodiment of the present invention. DETAILED DESCRIPTION

[0043] The following is further described in detail through specific implementation methods:

[0044] Example:

[0045] A method for adjusting ground motion parameters for non-uniform sites across different site categories in mountainous areas is shown in the attached Figure 2 As shown, the following steps are included:

[0046] Step 1: Determine the relationship between the structure and the site and the structural boundary range.

[0047] Among them, the relationship between the structure and the site and the structural boundary range refer to the specific location of the structure in the site.

[0048] Step 2: Determine the soil type, thickness of each soil layer and corresponding geotechnical characteristic parameters under the structure.

[0049] Among them, geotechnical characteristic parameters include soil density, cohesion, elastic modulus, shear modulus, friction angle and Poisson's ratio.

[0050] Step 3: Conduct a shear wave velocity experiment to obtain the shear wave velocity corresponding to each soil layer.

[0051] Step 4: Determine the site category of each location of the structure based on the thickness of each soil layer and the corresponding shear wave velocity in steps 2 and 3.

[0052] Step 5: Based on the position, thickness and geotechnical parameters of each soil layer obtained in step 2, multiple free field models of inclined bedrock non-uniform sites and overall finite element models (SSI models for short) considering soil-structure interaction are established by considering factors such as different site category proportions, bedrock inclination, soil layer thickness, and structure base width;

[0053] In this step, a fixed boundary is used at the bottom of the model, and the distance of 15 times the maximum soil thickness in the model outside the structure range on both sides is taken as the approximate infinite boundary.

[0054] Among them, the two model diagrams in this step are as follows: Figure 3 and Figure 4 shown.

[0055] Among them, the free field model of inclined bedrock non-uniform site is a model for analyzing the influence of inclined bedrock on the surface seismic response of the site without considering the influence of the structure.

[0056] Among them, the overall finite element model considering soil-structure interaction is a numerical model used to analyze and study the interaction between soil and structure. This model combines the finite element models of soil and structure to simulate and analyze the mechanical behavior and response of soil and structure under interaction conditions.

[0057] Step 6: According to the inclined bedrock model in step 5, a flat bedrock free field model and a flat bedrock SSI model corresponding to different site categories (thin soil side and thick soil side of inclined bedrock) are established;

[0058] The model diagram of this step is as follows: Figure 5 As shown, if the blue dotted line does not exist, it is a flat bedrock free field model, and if it exists, it is a flat bedrock SSI model.

[0059] Among them, the flat bedrock free field model and the flat bedrock SSI are used to analyze and study the surface seismic response and structural seismic response of the site when the bedrock is horizontal.

[0060] Step 7: Select the actual recorded bedrock earthquake motion to be vertically incident at the bottom of all models (the inclined bedrock non-uniform site free field model and SSI model in step 5 and the flat bedrock free field model and flat bedrock SSI model in step 6) for dynamic time history analysis.

[0061] In this step, at least 7 sets of actual recorded bedrock earthquake motions are selected to be incident vertically at the bottom of the model for dynamic analysis. Using multiple sets of actual recorded bedrock earthquake motion data can help improve the accuracy and reliability of earthquake engineering, promote the development of structural design, strengthen earthquake risk management, and promote research and specification formulation in the field of earthquake engineering.

[0062] Step 8: Draw the average surface earthquake acceleration response spectrum diagram of the corresponding positions of the vertical components at the bottom of the structure in the inclined bedrock free field model and the flat bedrock free field model obtained in step 7, the structural base shear force diagram and the average maximum layer displacement diagram of the inclined bedrock SSI model and the flat bedrock SSI model.

[0063] Step 9: Based on the average value diagram of the surface earthquake acceleration response spectrum of the flat bedrock free field model on the thick soil side and the thin soil side in step 8 and the response spectrum value obtained in step 7, the intersection of the site surface response spectrum of the flat bedrock model corresponding to the thick soil side and the thin soil side is used as the boundary to divide: 0-C seconds segment is a relatively high frequency segment, C-6 seconds is a relatively low frequency segment, where C is the intersection of the response spectrum;

[0064] The schematic diagram of this step is as follows: Figure 6 shown.

[0065] Step 10: Integrate the preset frequency band of the response spectrum obtained in step 8 and the relatively low-frequency segment divided in step 9 to obtain parameter γ. Considering that the first period of the structure is generally located in the relatively low-frequency segment, in this embodiment, the lower frequency band of the response spectrum is integrated to obtain parameter γ, where γ represents the difference between the average value of the surface earthquake response spectrum of the non-uniform site and the earthquake impact of the corresponding flat bedrock site. Wherein, parameter γ is calculated according to Figure 6 And formula (1) is used for calculation,

[0066]

[0067] Where f(T) is the surface response spectrum value of the inclined bedrock model at the value point x; Fthin(T) is the surface response spectrum value of the flat bedrock free field corresponding to the thin soil side; Fthick(T) is the surface response spectrum value of the flat bedrock free field corresponding to the thick soil side;

[0068] The closer γ is to 1, the closer the seismic response of the inhomogeneous site is to the thin soil side; the closer γ is to 2, the closer the seismic response of the inhomogeneous site is to the thick soil side.

[0069] As attached Figure 7 -Attached Fig.10 As shown in Figure 2, the earthquake acceleration response spectrum of some free-field models is shown, and Table 2 shows the γ calculated from the average spectrum of the column base.

[0070]

[0071] It can be seen from the above chart that the γ calculated from the average spectrum of the structure base is not greater than (1+β), where β is the proportion of the structure in the thick soil side.

[0072] Step 11: Obtain the structural base shear force and maximum layer displacement in the inclined bedrock SSI model and the corresponding flat bedrock SSI model according to step 7, and use the constructed parameter γ v and γ D They respectively characterize the closeness between the seismic response of the inclined bedrock SSI model structure and the seismic response of the corresponding flat bedrock site, where

[0073] Among them, Δ D is the average value of the maximum interlayer displacement angle of the inclined bedrock SSI model structure under the action of each seismic wave, Δ Dh1 is the average value of the maximum interlayer displacement angle of the flat bedrock SSI model structure corresponding to the thin soil side site category under the action of each seismic wave, Δ Dh2 is the average value of the maximum interlayer displacement angle of the flat bedrock SSI model structure corresponding to the thick soil side site category under the action of each seismic wave, V is the average base shear force of the inclined bedrock SSI model structure, V h1 is the average shear force of the flat bedrock SSI model structure corresponding to the thin soil side site category, V h2 It is the average base shear force of the SSI model structure on flat bedrock corresponding to the thick soil side site category.

[0074] in, Fig.11 The increase of the base shear force relative to h1 corresponding to the SSI model of flat bedrock is shown in Table 3. The γ calculated with different parameters is shown in Table 3. v value.

[0075] Table 3 γ calculated with different parameters v value

[0076]

[0077] Table 3 SSI model γ of inclined bedrock with thick soil side site ratio of 1 / 6, 3 / 6, and 5 / 6 v The maximum values ​​are 1.088, 1.214, and 1.409, all of which are less than (1+β), where β is the proportion of the structure in the thick soil side.

[0078] Fig.12 is the maximum interlayer displacement relative to h1 corresponding to the SSI model of flat bedrock, and Table 4 is the γ calculated with different parametersD value.

[0079] Table 4 γ calculated with different parameters D value

[0080]

[0081] From Table 4, we can see that the SSI model γ of the inclined bedrock with the thick soil side accounting for 1 / 6, 3 / 6, and 5 / 6 D The maximum values ​​are 1.101, 1.349, and 1.556, all of which are less than (1+β), where β is the proportion of the structure in the thick soil side.

[0082] Step 12: According to step 10 and step 11, get γ and γ V and γ D The values ​​are all less than or equal to 1+β, where β is the proportion of the structure on the thick soil side. When there are two types of site categories, β = site area of ​​the higher site category / total site area;

[0083] Step 13: Based on the statistical results of step 12, the seismic response of the structure on the inclined bedrock non-uniform site can be interpolated according to the proportion of the structure in the thick soil side β and the structural seismic response of the corresponding site category, so as to guide the calculation of seismic actions and seismic verification of structures located across different site categories. The seismic motion parameter adjustment formula is: seismic influence coefficient of the structure on the inclined bedrock non-uniform site = β*(seismic influence coefficient calculated for the higher site category - seismic influence coefficient calculated for the lower site category) + seismic influence coefficient calculated for the lower category.

[0084] When there are both Class I and Class II sites in this step, β = Class II site area / total site area; the seismic influence coefficient of the structure on the inclined bedrock non-uniform site = β*(seismic influence coefficient calculated for Class II site category - seismic influence coefficient calculated for Class I site category) + seismic influence coefficient calculated for Class I site category.

[0085] When there are both Class II and Class III sites in this step, β = Class III site area / total site area, and the structural seismic response is calculated by interpolation based on the site category ratio β; the structural seismic influence coefficient on the inclined bedrock non-uniform site = β*(seismic influence coefficient calculated for Class III site category - seismic influence coefficient calculated for Class II site category) + seismic influence coefficient calculated for Class II site category.

[0086] The simplified interpolation method for determining seismic motion based on site category proposed in the present invention has seismic responses calculated after interpolation that are greater than or equal to the seismic responses actually calculated. The interpolation method for calculating seismic responses using the present invention is still relatively safe, but it is more economical than the traditional method of determining seismic effects based on the most unfavorable site. The method is simple and easy to promote and apply.

[0087] The above is only an embodiment of the present invention, and the common knowledge such as the known specific technical schemes and / or characteristics in the scheme is not described in detail here. It should be pointed out that for those skilled in the art, several variations and improvements can be made without departing from the technical scheme of the present invention. In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, or it can be the internal connection of two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances. The scope of protection claimed in this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A method for adjusting ground motion parameters of non-uniform sites across different site categories in mountainous areas, characterized in that: The following steps are involved: Step 1: Determine the relationship between the structure and the site and the structural boundary range; Step 2: Determine the soil type, thickness of each soil layer and corresponding geotechnical characteristic parameters under the structure; Step 3: Conduct a shear wave velocity experiment to obtain the shear wave velocity corresponding to each soil layer; Step 4: Determine the site category of each location of the structure based on the thickness of each soil layer and the corresponding shear wave velocity in steps 2 and 3; Step 5: Based on the position, thickness and geotechnical parameters of each soil layer obtained in step 2, multiple free field models of inclined bedrock non-uniform sites and an overall finite element model considering soil-structure interaction are established by considering different site category proportions, bedrock inclination, soil layer thickness, and structural base width factors; Step 6: Based on the inclined bedrock model in step 5, establish a flat bedrock free field model and a flat bedrock SSI model corresponding to different site categories; Step 7: Select the actual recorded bedrock ground motion incident vertically at the bottom of all models to perform dynamic time history analysis; Step 8: Draw the average value diagram of surface earthquake acceleration response spectrum at the corresponding position of the vertical components at the bottom of the structure in the inclined bedrock free field model and the flat bedrock free field model, the structural base shear force diagram and the average value diagram of maximum layer displacement of the inclined bedrock SSI model and the flat bedrock SSI model obtained in step 7; Step 9: Based on the average value diagram of the surface earthquake acceleration response spectrum of the flat bedrock free field model on the thick soil side and the thin soil side in step 8 and the response spectrum value obtained in step 7, the intersection of the site surface response spectrum of the flat bedrock model corresponding to the thick soil side and the thin soil side is used as the boundary to divide: 0-C seconds segment is a relatively high frequency segment, C-6 seconds is a relatively low frequency segment, where C is the intersection of the response spectrum; Step 10: Integrate the response spectrum obtained in step 8 and the relatively low-frequency segment divided in step 9 to obtain parameter γ, where γ represents the difference between the average value of the surface seismic response spectrum of the inhomogeneous site and the seismic response of the corresponding flat bedrock site, where Where f(T) is the surface response spectrum value of the inclined bedrock model at the value point x; F thin (T) is the surface response spectrum value of the flat bedrock free field corresponding to the thin soil side; F thick (T) is the surface response spectrum value of the flat bedrock free field corresponding to the thick soil side; Step 11: Obtain the structural base shear force and maximum layer displacement in the inclined bedrock SSI model and the corresponding flat bedrock SSI model according to step 7, and use the constructed parameter γ v and γ D They respectively characterize the closeness between the seismic response of the inclined bedrock SSI model structure and the seismic response of the corresponding flat bedrock site, where Among them, Δ D is the average value of the maximum interlayer displacement angle of the inclined bedrock SSI model structure under the action of each seismic wave, Δ Dh1 is the average value of the maximum interlayer displacement angle of the flat bedrock SSI model structure corresponding to the thin soil side site category under the action of each seismic wave, Δ Dh2 is the average value of the maximum interlayer displacement angle of the flat bedrock SSI model structure corresponding to the thick soil side site category under the action of each seismic wave, V is the average base shear force of the inclined bedrock SSI model structure, V h1 is the average shear force of the flat bedrock SSI model structure corresponding to the thin soil side site category, V h2 is the average base shear force of the SSI model structure on flat bedrock corresponding to the thick soil side site category; Step 12: According to step 10 and step 11, get γ and γ V and γ D The values ​​are all less than or equal to 1+β, where β is the proportion of the structure on the thick soil side. When there are two types of site categories, β = site area of ​​the higher site category / total site area; Step 13: According to the statistical results of step 12, the seismic response of the structure on the inclined bedrock non-uniform site can be interpolated according to the proportion of the structure in the thick soil side range β and the structural seismic response of the corresponding site category, so as to guide the calculation of seismic action and seismic verification of structures located across different site categories. The seismic motion parameter adjustment formula is: seismic influence coefficient of the structure on the inclined bedrock non-uniform site = β*(seismic influence coefficient calculated for the higher site category - seismic influence coefficient calculated for the lower site category) + seismic influence coefficient calculated for the lower category; The geotechnical characteristic parameters in step 2 include: soil density, cohesion, elastic modulus, shear modulus, friction angle and Poisson's ratio; when there are Class II and Class III sites in steps 12 and 13, β=Class III site area / total site area, and the structural seismic response is calculated by interpolation based on the site category proportion β; the structural seismic influence coefficient on the inclined bedrock non-uniform site=β*(seismic influence coefficient calculated for Class III site category-seismic influence coefficient calculated for Class II site category)+seismic influence coefficient calculated for Class II site category.

2. The method for adjusting ground motion parameters of non-uniform sites across different site categories in mountainous areas according to claim 1 is characterized in that: In step 7, at least 7 groups of actual recorded bedrock earthquake motions are selected to vertically incident on the bottom of the model for dynamic time history analysis.

3. The method for adjusting ground motion parameters of non-uniform sites across different site categories in mountainous areas according to claim 1, characterized in that: Step 10, Step 11 γ, γ V and γ D The value is obtained by calculating the integral of the response spectrum based on the C-6 second period segment. Its value is between 1 and 2, representing the degree of difference between the surface seismic motion parameters of the inclined bedrock site and the corresponding flat bedrock site. The closer the value is to 1, the closer its seismic response is to the corresponding seismic response of the thin soil side site category; the closer the value is to 2, the closer its seismic response is to the corresponding seismic response of the thick soil side site category.

4. The method for adjusting ground motion parameters of non-uniform sites across different site categories in mountainous areas according to claim 1, characterized in that: When there are Class I and Class II sites in steps 12 and 13, β=Class II site area / total site area; the seismic influence coefficient of the structure on the inclined bedrock non-uniform site=β*(seismic influence coefficient calculated for Class II site category-seismic influence coefficient calculated for Class I site category)+seismic influence coefficient calculated for Class I site category.

5. The method for adjusting ground motion parameters of non-uniform sites across different site categories in mountainous areas according to claim 1, characterized in that: In the steps 5 and 6, a fixed boundary is used at the bottom of all finite element models, and a distance of 15 times the maximum soil thickness in the model outside the structural range is taken on both sides as an approximate infinite boundary.

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