A method for determining standard earthquake action based on the whole process of structural nonlinearity

Abstract

The present invention relates to a method for determining standard earthquake action based on the whole process of structural nonlinearity, which includes performing n-order vibration mode pushover analysis on a structure to obtain parameters of the structure in the elastic stage; calculating and obtaining the structure's initial vibration mode combined lateral force distribution mode; obtaining the structure vertex displacement after the kth update stage loading is completed based on the pre-constructed update stage k; obtaining the structure instantaneous vibration mode combined lateral force distribution mode of the kth update stage; determining the structure capacity spectrum curve by calculation based on the instantaneous vibration mode combined lateral force distribution mode of the structure in each stage, and obtaining the structure target displacement by combining the elastic-plastic demand spectrum curve; determining the structure standard earthquake action by calculation based on the instantaneous vibration mode combined lateral force distribution mode of the structure in the kth update stage and the structure target displacement. It takes into account the whole process of the nonlinearity of the structure under earthquake action, and improves the accuracy of the nonlinear static analysis method in estimating the earthquake demand of the structure under earthquake action.

Description

Technical Field

[0001] The invention relates to the technical field of earthquake resistance of building structures, and in particular to a method for determining standard earthquake action based on the whole process of structural nonlinearity. Background Art

[0002] When the seismic demand analysis is performed on the structure under the action of earthquake, the seismic action on the structure can be represented by the inertial force generated by the input seismic waves on the structure. Commonly used methods are: ① Solve the motion equation of the multi-degree-of-freedom system under the action of ground motion generated by seismic waves based on the time-history analysis method to determine the seismic demand of the structure such as internal force and deformation. ② Nonlinear static analysis decomposes the mutually coupled vibration modes in the motion equation of the multi-degree-of-freedom system and converts it into solving the maximum seismic action of each particle under each vibration mode, that is, the seismic action of the structure is represented by the lateral force distribution mode combined with the response spectrum under each vibration mode applied to the structure to represent the structural inertial force. Finally, the seismic demand of each vibration mode is determined by the "square sum square root" (SRSS) method.

[0003] The time-history analysis method is used to determine the seismic action and seismic demand of the structure, but it is inconvenient to use due to the huge amount of calculation. The traditional nonlinear analysis method is used to determine the seismic action and seismic demand, but the analysis process is relatively simple and the calculation amount is small, but the accuracy is low.

[0004] The lateral force loading mode in traditional nonlinear static analysis methods mainly adopts the constant lateral force distribution mode, such as uniform, inverted triangle and various vibration modes. Commonly used traditional nonlinear static analysis methods include: modal pushover analysis method and adaptive pushover analysis method. The adaptive pushover analysis method takes into account the redistribution of internal forces when the structure enters the nonlinear state, and continuously adjusts the structural vibration parameters to take into account the degradation of component stiffness when the structure enters the nonlinear state.

[0005] Traditional nonlinear static analysis methods have the following problems:

[0006] (1) Currently, the commonly used nonlinear static analysis methods, such as the modal pushover analysis method, adopt a constant lateral force distribution model, which is not comprehensive enough and has the problem of inaccurate earthquake demand prediction;

[0007] (2) The adaptive pushover analysis method takes into account the redistribution of the internal forces of the structure when it enters a nonlinear state. However, the lateral force loading method updates each loading sub-step, which results in a large amount of calculation. The amount of calculation is even almost the same as that of the nonlinear dynamic time-history analysis method, which is difficult to calculate.

[0008] (3) Nonlinear static analysis methods such as modal pushover analysis method and adaptive pushover analysis method determine the total response of the structure through SRSS or CQC combination. This combination is not comprehensive enough, resulting in inaccurate determination of structural seismic demand. Summary of the invention

[0009] 1. Technical issues to be resolved

[0010] In view of the above-mentioned shortcomings and deficiencies of the prior art, the present invention provides a standard seismic action determination method based on the entire process of structural nonlinearity, which takes into account the entire nonlinear process of the structure under seismic action, and improves the technical problem of the accuracy of nonlinear static analysis methods in estimating the seismic demands of the structure under seismic action.

[0011] (II) Technical solution

[0012] In order to achieve the above object, the main technical solution adopted by the present invention includes the following steps:

[0013] 101. Perform n-order mode pushover analysis on the structure to obtain parameters of the structure in the elastic stage;

[0014] 102. Calculate the obtained elastic phase parameters to obtain the initial vibration mode combined lateral force distribution mode of the structure.

[0015] 103. Update stage k based on the pre-built structural lateral force distribution pattern, and obtain the structural vertex displacement after the loading of the kth update stage is completed.

[0016] According to the obtained structure vertex displacement Get the instantaneous vibration mode combined lateral force distribution mode of the structure in the kth update stage

[0017] 104. Displace the structure vertices With the limit displacement u max For comparison:

[0018] If the structure vertex displacement Greater than the limit displacement u max , execute step 105;

[0019] Otherwise, update stage k=k+1 and execute step 103;

[0020] 105. Based on the obtained instantaneous vibration mode combination lateral force distribution mode of the structure in the kth update stage Calculate and determine the structural capacity spectrum curve and obtain the structural target displacement u j ;

[0021] 106. Combination of lateral force distribution modes based on the instantaneous vibration mode of the structure in the kth update stage and the structural target displacement u j , determine the standard earthquake action F of the structure by calculation j .

[0022] Optionally, the standard earthquake action determination method further includes:

[0023] Based on the structural standard earthquake action F determined by the calculation j , obtain the structure under standard earthquake action F j The structural seismic demand envelope value when acting.

[0024] Optionally, before step 101, the method further includes:

[0025] According to the cumulative participation coefficient of the structural vibration mode mass, the number of vibration modes n of the n-order vibration mode is determined;

[0026] The cumulative participation coefficient of the structural modal mass exceeds 90%;

[0027] In step 101, the elastic phase parameters obtained include:

[0028] Structural n-order vibration mode vector Structural mass m, structural vibration mode participation coefficient Structural spectral acceleration and mode combination coefficient

[0029] Optionally, the step 102 specifically includes:

[0030] 102a. Determine the initial lateral force distribution mode of the nth vibration mode of the structure;

[0031] 102b. Combine the multiple n-th vibration mode initial lateral force distribution modes of the structure according to a pre-constructed combination method to obtain j initial vibration mode combined lateral force distribution modes.

[0032] Optionally, the step 103 specifically includes:

[0033] 103a. Determine the displacement of the structure at the kth update stage from the pushover to the structure vertex The first vibration mode vector of the structure

[0034] 103b, according to the first vibration mode vector of the structure obtained Obtain the parameters of the nth vibration mode of the structure at the kth update stage;

[0035] 103c. Acquire the instantaneous lateral force distribution mode of the nth vibration mode structure in the kth updating stage according to the acquired parameters of the nth vibration mode in the kth updating stage;

[0036] 103d. According to the instantaneous lateral force distribution mode of the n-th vibration mode structure in the k-th update stage, multiple instantaneous lateral force distribution modes of the n-th vibration mode structure in the k-th update stage are combined according to a pre-constructed combination method to obtain j instantaneous vibration mode combined lateral force distribution modes of the structure in the k-th update stage.

[0037] Optionally, the kth update stage parameters include: the kth update stage vibration mode vector Participation coefficient of the kth update stage Spectral acceleration at the kth update stage and the kth update stage mode combination coefficient

[0038] Optionally, the limit displacement u max is the maximum inter-story displacement angle of the structure, and the maximum inter-story displacement angle of the structure is 2%.

[0039] Optionally, the step 105 specifically includes:

[0040] 105a. Based on the instantaneous vibration mode combined lateral force distribution mode of the structure in the kth update stage obtained, the instantaneous vibration mode combined lateral force distribution mode is obtained. Structural floor deformation at the kth update stage and floor shear

[0041] 105b, according to the kth update stage structural floor deformation and floor shear Obtain the formula for the capability spectrum curve of the equivalent single-degree-of-freedom system;

[0042] 105c, according to the displacement of the structure vertices Determine the instantaneous vibration mode combination lateral force distribution mode of the structure at the kth update stage The corresponding ductility coefficient of the equivalent single degree of freedom system

[0043] 105d, according to the ductility coefficient of the equivalent single degree of freedom system at the kth update stage Determine the formula of the elastic-plastic demand spectrum curve of the equivalent single-degree-of-freedom system in the kth update stage;

[0044] 105e. Determine the instantaneous vibration mode combination lateral force distribution mode according to the above-mentioned equivalent single-degree-of-freedom system capacity spectrum curve formula and the equivalent single-degree-of-freedom system elastic-plastic demand spectrum curve formula. The corresponding equivalent single-degree-of-freedom system target spectrum displacement S dj , based on the target spectrum displacement S of the equivalent single degree of freedom system dj The target displacement u of the structure is calculated j .

[0045] Optionally, the equivalent single-degree-of-freedom system capability spectrum curve formula is:

[0046]

[0047] The formula of the elastoplastic demand spectrum curve of the equivalent single degree of freedom system is:

[0048]

[0049] Based on the target spectrum displacement S of the equivalent single degree of freedom system dj The target displacement u of the structure is calculated j , the calculation formula is:

[0050] u j =γ j φ j S dj .

[0051] Optionally, the structural standard earthquake action F j The calculation formula is:

[0052]

[0053] Based on the standard earthquake action F j Calculate and obtain the instantaneous vibration mode and lateral force distribution mode of the structure Structural seismic demand S j , based on the structural seismic demand S j , obtain the total seismic response S of the structure;

[0054] The total structural seismic response S is the structural seismic demand S j The envelope value of .

[0055] (III) Beneficial effects

[0056] The present invention provides a method for determining standard seismic actions based on the entire nonlinear process of the structure, which can take into account the relative contribution and action direction of each vibration mode of the structure, and the nonlinear internal force redistribution process of the structure in the entire nonlinear process, and takes the yielding of a group of similar components as the structural loading update stage, and updates the lateral force distribution mode of the structure in the entire nonlinear process, thereby greatly reducing the amount of calculation while ensuring the accuracy of predicting the seismic demand of the structure, achieving the purpose of taking into account the lateral force loading mode, the directions of each vibration mode, the relative contributions, and the entire nonlinear process of the structure under the action of the earthquake, and improving the accuracy of estimating the seismic demand of the structure under the action of the earthquake and the effectiveness of predicting the seismic demand of the structure by the nonlinear static analysis method. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] Figure 1 A schematic flow chart of a method for determining standard earthquake action based on the entire process of structural nonlinearity provided by an embodiment of the present invention;

[0058] Figure 2 A schematic diagram of a process for determining a standard earthquake action based on the entire process of structural nonlinearity provided by an embodiment of the present invention;

[0059] Figure 3 It is a schematic diagram of a structural plane and a schematic diagram of a structural elevation in one embodiment of the present invention;

[0060] Figure 4 A schematic diagram of a lateral force distribution mode of a combination of vibration modes loaded in multiple update stages provided in one embodiment of the present invention;

[0061] Figure 5 A schematic diagram of a seismic influence coefficient curve determined by selecting ground motions provided in one embodiment of the present invention;

[0062] Figure 6 A schematic diagram of a comparison curve of inter-layer displacement angles of a structure provided by an embodiment of the present invention;

[0063] Figure 7 A schematic diagram of a comparison curve of overall error of inter-layer displacement angle of a structure provided by an embodiment of the present invention;

[0064] Figure 8 A schematic diagram of a structural plane and a schematic diagram of a structural elevation in another embodiment of the present invention;

[0065] Fig. 9 for Figure 8 A schematic diagram of a seismic influence coefficient curve determined by selecting a seismic motion provided in an embodiment of the present invention;

[0066] Fig.10 for Fig. 9 A schematic diagram of a comparison curve of the structural interlayer displacement angle provided by the embodiment;

[0067] Fig.11 for Fig.10 Schematic diagram of the overall error comparison curve of the inter-layer displacement angle of the structure provided in the embodiment. DETAILED DESCRIPTION

[0068] In order to better explain the present invention and facilitate understanding, the present invention is described in detail below in conjunction with the accompanying drawings through specific implementation methods. It is understood that the specific embodiments described below are only used to explain the relevant inventions, rather than to limit the invention. It should also be noted that the embodiments and features in the embodiments of this application can be combined with each other in the absence of conflict; for ease of description, only the parts related to the invention are shown in the accompanying drawings.

[0069] like Figure 1 As shown, Figure 1 A schematic flow chart of a method for determining a standard seismic action based on the entire process of structural nonlinearity provided by an embodiment of the present invention is shown. The method for determining a standard seismic action includes:

[0070] 101. Perform n-order modal pushover analysis on the structure to obtain parameters of the structure in the elastic stage. In this embodiment, specifically, the structure is imported into Perform3D software to perform n-order modal pushover analysis on the structure.

[0071] The parameters of the structure in the elastic stage may include: structural mass m, structural n-order vibration vector Structural vibration mode participation factor Structural spectral acceleration and mode combination coefficient Etc. The nth-order vibration mode vector of the structure is the vibration mode vector corresponding to the n vibration mode of the structure.

[0072] 102. Calculate the elastic phase parameters obtained according to the pre-built Matlab model to obtain the initial vibration mode combined lateral force distribution mode of the structure.

[0073] 103. Update stage k based on the pre-built structural lateral force distribution pattern, and obtain the structure vertex displacement after the loading of the kth update stage is completed.

[0074] According to the obtained structure vertex displacement Get the instantaneous vibration mode combined lateral force distribution mode of the structure in the kth update stage Specifically, in this embodiment, the structure vertex is displaced Input into the pre-built Matlab model to obtain the instantaneous vibration mode combination lateral force distribution mode of the structure at the kth update stage

[0075] In this embodiment, the pre-constructed structural lateral force distribution pattern update stage k is specifically: according to the yielding of a batch of similar components in the structure, the update stage of the structural lateral force distribution pattern is divided to obtain the structural lateral force distribution pattern update stage k.

[0076] Of course, in practical applications, the structural lateral force distribution mode updating stage k is divided according to the actual structure and is not limited here.

[0077] 104. Displace the structure vertices With the limit displacement u max For comparison:

[0078] If the structure vertex displacement Greater than the limit displacement u max , execute step 105;

[0079] Otherwise, update stage k=k+1 and execute step 103;

[0080] 105. Based on the obtained instantaneous vibration mode combination lateral force distribution mode of the structure in the kth update stage Determine the structural capacity spectrum curve by calculation and obtain the structural target displacement u j ;

[0081] In this embodiment, steps 103 and 105 may be performed in Perform3D software.

[0082] 106. Combination of lateral force distribution modes based on the instantaneous vibration mode of the structure in the kth update stage and the structural target displacement u j , determine the standard earthquake action F of the structure by calculation j .

[0083] The software used in this embodiment mainly includes Perform3D and Matlab, but in actual applications, other software or other means that can achieve the same purpose can also be used, which is not limited here.

[0084] In practical applications, the method for determining the standard seismic action may further include: j , obtain the structure under standard earthquake action F j The structural seismic demand envelope value when acting.

[0085] In practical applications, the structural seismic demand envelope value can be used to verify the obtained structural standard seismic action F j .

[0086] The method for determining the standard seismic action based on the entire process of structural nonlinearity provided in this embodiment considers the redistribution of internal forces in the entire process of nonlinearity of the structure under seismic action, and takes into account the directions and relative contributions of each vibration mode and the entire process of nonlinearity of the structure under seismic action. The present invention is based on a lateral force loading mode of a multi-stage instantaneous vibration mode combination, and establishes a standard seismic action that considers the entire process of nonlinearity of the structure under the action of an earthquake, providing a research basis for a structural seismic design method that reflects the entire process of nonlinearity of the structure under the action of an earthquake, and improving the accuracy of the nonlinear static analysis method in estimating the seismic demand of the structure under the action of an earthquake.

[0087] Specifically, in some other embodiments, before step 101, the number n of the n-order vibration mode is determined by a cumulative participation coefficient of the structural vibration mode mass, and the cumulative participation coefficient of the structural vibration mode mass exceeds 90%.

[0088] For step 102, the elastic phase parameters obtained are calculated to obtain the initial vibration mode combined lateral force distribution mode of the structure. The specific steps may include:

[0089] Determine the initial lateral force distribution mode of the nth vibration mode of the structure according to the parameters of the above structure in the elastic stage;

[0090] Combine the multiple n-th vibration mode initial lateral force distribution modes of the structure according to the pre-constructed combination method to obtain j initial vibration mode combined lateral force distribution modes

[0091] Specifically, in this embodiment, the pre-constructed combination mode is that the initial lateral force distribution mode is combined according to "+" and "-" to determine j initial vibration mode combination lateral force distribution modes. Among them, the initial lateral force distribution mode corresponding to the first vibration mode is taken as "+", and the initial lateral force distribution modes corresponding to the other vibration modes are respectively taken as "+" and "-", and are arranged and combined according to "+" and "-".

[0092] In order to better understand the combination method, a specific combination scenario is used as an example. Taking the first three vibration modes of the structure in the same direction as an example, the initial lateral force distribution mode is combined according to "+" and "-". The initial lateral force distribution mode corresponding to the first vibration mode is taken as "+", that is, the initial vibration mode of the structure is combined with the lateral force distribution mode. for:

[0093]

[0094] Wherein, j is the total number of combinations of initial lateral force distribution patterns having “+” and “-”.

[0095] In this embodiment, considering the first three vibration modes of the structure in the same direction, the total number of initial lateral force distribution mode combinations j is 4, j = 1, 2, 3, 4. The initial vibration mode combination lateral force distribution mode of the structure There are four lateral force distribution modes:

[0096]

[0097] Figure 2 A schematic diagram of a process for determining a standard earthquake action based on a full process of structural nonlinearity is provided for another embodiment of the present invention. Figure 2 As shown, according to the yielding of a group of similar components in the structure, the updating stages of the structural lateral force distribution pattern are divided to obtain the updating stage k of the structural lateral force distribution pattern.

[0098] In some practical applications, the update stage k is divided by the yielding of a group of similar components in the structure. For example, the yielding of a group of similar beam components is divided into update stage 1, the yielding of a group of similar frame column components is divided into update stage 2, and so on.

[0099] Of course, in some other practical applications, there are many other update stages for determining the yield division of batches of similar components, which are confirmed based on the actual structure and are not restricted here.

[0100] In step 103, the displacement of the structure vertex pushed over in the kth update phase is determined. The first vibration mode vector of the structure According to the first vibration mode vector of the structure obtained Obtain the parameters of the nth vibration mode of the structure at the kth update stage;

[0101] In this embodiment, the kth update stage parameters include at least: the kth update stage vibration mode vector Participation coefficient of the kth update stage Spectral acceleration at the kth update stage And the modal combination coefficient of the kth update stage wait.

[0102] According to the obtained parameters of the nth vibration mode at the kth update stage, obtaining the instantaneous lateral force distribution mode of the nth vibration mode structure at the kth update stage;

[0103] According to the instantaneous lateral force distribution mode of the n-th vibration mode structure at the k-th update stage, multiple instantaneous lateral force distribution modes of the n-th vibration mode structure at the k-th update stage are combined according to a pre-constructed combination method to obtain j instantaneous vibration mode combined lateral force distribution modes of the structure at the k-th update stage

[0104] Specifically, in this embodiment, the pre-constructed combination mode is to determine j instantaneous vibration mode combination lateral force distribution modes according to the combination of "+" and "-" of the instantaneous lateral force distribution mode of the n-th vibration mode structure in the k-th update stage. Among them, the instantaneous lateral force distribution mode corresponding to the first vibration mode is taken as "+", and the instantaneous lateral force distribution modes corresponding to the other vibration modes are respectively taken as "+" and "-", and are arranged and combined according to "+" and "-".

[0105] In order to better understand the combination method, a specific combination scenario is used as an example. Taking the first three vibration modes of the structure in the same direction as an example, the instantaneous lateral force distribution mode is combined according to "+" and "-". The instantaneous vibration mode lateral force distribution mode corresponding to the first vibration mode is taken as "+", that is, the instantaneous vibration mode combined lateral force distribution mode of the structure for:

[0106]

[0107] Wherein, j is the total number of permutations and combinations of instantaneous lateral force distribution patterns having “+” and “-”.

[0108] In this embodiment, considering the first three vibration modes of the structure in the same direction, the total number of instantaneous lateral force distribution mode combinations j is 4, j = 1, 2, 3, 4. The instantaneous vibration mode combination lateral force distribution mode of the structure There are four lateral force distribution modes:

[0109]

[0110] In some other embodiments, the structure vertex displacement should also be Perform detection, specifically, detect the displacement of the structure vertices Is it greater than the limit displacement u max .

[0111] The structure vertex displacement Combined lateral force distribution mode with the instantaneous vibration mode of the jth combination The corresponding structure vertex displacement

[0112] In this embodiment, the limit displacement u max is the maximum inter-story displacement angle of the structure, and the maximum inter-story displacement angle of the structure is 2%.

[0113] If the structure vertex displacement Less than or equal to the limit displacement u max , then the update stage k = k + 1, and the lateral force distribution mode is re-combined based on the instantaneous vibration mode of the kth update stage The kth update stage parameters of the structure at the k=k+1th update stage are determined, and the instantaneous vibration mode combined lateral force distribution mode of the structure at the k=k+1th update stage is obtained.

[0114]

[0115] If the structure vertex displacement u (k) Greater than the limit displacement u max , then proceed to the next step, based on the instantaneous vibration mode combined lateral force distribution mode of the structure in the kth update stage obtained, determine the structural capacity spectrum curve by calculation, and obtain the structural target displacement u j .

[0116] In this embodiment, for step 105, based on the instantaneous vibration mode combination of the structure in the kth update stage obtained, the lateral force distribution mode Determine the structural capacity spectrum curve by calculation and obtain the structural target displacement u j The specific steps are:

[0117] Based on the instantaneous vibration mode combined lateral force distribution mode of the structure in the kth update stage obtained, the instantaneous vibration mode combined lateral force distribution mode is obtained Structural floor deformation at the kth update stage and floor shear

[0118] The lateral force distribution mode based on the instantaneous vibration mode combination of the kth update stage structure and the jth combination mode Corresponding structural floor deformation and floor shear Obtain the formula for the capability spectrum curve of the equivalent single-degree-of-freedom system;

[0119] The formula of the equivalent single degree of freedom system capability spectrum curve is:

[0120]

[0121] In the formula, is the spectral acceleration in the capacity spectrum curve of the equivalent single-degree-of-freedom system in the jth combination and the kth update stage; is the spectral displacement in the capacity spectrum curve of the equivalent single-degree-of-freedom system in the j-th combination and the k-th updating stage; I is the unit vector, and T is the natural vibration period of the structure.

[0122] According to the structure at the kth update stage, the structure vertex displacement Determine the instantaneous vibration mode combined lateral force distribution mode of the structure at the kth update stage The corresponding ductility coefficient of the equivalent single degree of freedom system

[0123] According to the ductility coefficient of the equivalent single degree of freedom system at the kth update stage Determine the formula of the elastic-plastic demand spectrum curve of the equivalent single-degree-of-freedom system in the kth update stage;

[0124] The formula of the elastoplastic demand spectrum curve of the equivalent single degree of freedom system is:

[0125]

[0126] In the formula, is the elastic spectral acceleration with a damping ratio of ξ; is the lateral force distribution mode combined with the instantaneous vibration mode of the jth combination mode The corresponding strength reduction factor, T is the natural vibration period of the structure.

[0127] According to the above-mentioned equivalent single-degree-of-freedom system capacity spectrum curve and equivalent single-degree-of-freedom system elastic-plastic demand spectrum curve, the instantaneous vibration mode combined with the jth combination mode is determined. The corresponding equivalent single-degree-of-freedom system target spectrum displacement S dj , based on the target spectrum displacement S of the equivalent single degree of freedom system dj The target displacement u of the structure is calculated j .

[0128] The target spectrum displacement S of the above equivalent single degree of freedom system is dj is the intersection of the capacity spectrum curve of the equivalent single-degree-of-freedom system and the elastic-plastic demand spectrum curve of the equivalent single-degree-of-freedom system. In this embodiment, the target spectrum displacement S based on the equivalent single-degree-of-freedom system dj The target displacement u of the structure is calculated j , the calculation formula is:

[0129] u j =γ j φ j S dj .

[0130] Combination of lateral force distribution modes based on the instantaneous vibration mode of the structure in the kth update stage And the instantaneous vibration mode combined lateral force distribution mode of the structure in the kth update stage Push over to the target displacement u of the structure j , determine the lateral force distribution mode combined with the instantaneous vibration mode of the jth combination mode The corresponding structural standard earthquake action F j .

[0131] In this embodiment, the structural standard earthquake action F j The calculation formula is:

[0132]

[0133] For example, the structural standard earthquake action F j for:

[0134]

[0135] Taking the first three updated stage vibration modes of the structure in the same direction as an example, the standard structural seismic actions corresponding to the lateral force distribution modes of the four instantaneous vibration modes include:

[0136]

[0137] Furthermore, for the standard earthquake action F j Calculate and obtain the instantaneous vibration mode and lateral force distribution mode of the structure Structural seismic demand S j , based on the structural seismic demand S j , obtain the total seismic response S of the structure; the total seismic response S of the structure is the seismic demand S of the structure j The envelope value of .

[0138] In order to better understand the present invention, the following Figures 3 to 7 Show a more specific real-world example.

[0139] This embodiment provides a building structure, which adopts a 5×5 span 10-story reinforced concrete frame structure, with a structural column distance of 8m and a floor height of 3m. Figure 3 As shown, Figure 3 (a) shows a schematic plan view of the building structure in this embodiment, Figure 3 (b) shows a schematic elevation view of the building structure in this embodiment.

[0140] The building structure design intensity is 7 degrees, the seismic design group is the first group, the site category is the second category, and the dead load and live load applied to the structure floor are 5kN / m 2 and 2kN / m 2 The cross-sectional dimensions and reinforcement conditions of structural members are shown in Table 1.

[0141] Table 1 Structural member cross-sectional dimensions and reinforcement

[0142]

[0143]

[0144] Based on the above structure modal mass cumulative participation coefficient exceeding 90%, the number of modal modes n of the n-order modal mode is selected to be 3, where n=1, 2, 3.

[0145] Perform pushover analysis of the third-order vibration mode in the same direction on this structure to obtain the parameters of the elastic stage of this structure: the n-order vibration mode vector of the structure Structural mass m, structural vibration mode participation coefficient Structural spectral acceleration and mode combination coefficient

[0146] According to the elastic stage parameters obtained above, the initial vibration mode combined lateral force distribution mode of the structure is obtained. Right now and

[0147] In this embodiment, according to the yielding of a batch of similar components of the structure, the updating stage of the structural lateral force distribution mode is divided to obtain the structural lateral force distribution mode updating stage k. Specifically, the lateral force is updated when a batch of similar frame beam components yield, and the lateral force is updated when a batch of similar frame column components yield. The updating stage k of the structural lateral force distribution mode is taken as 2. The lateral force of the structure changes from the initial stage to the updating stage 1 to the updating stage 2 during the overturning process. Based on the structural lateral force distribution mode updating stage k, the instantaneous vibration mode combined lateral force distribution mode of the structure in the kth updating stage is obtained.

[0148] like Figure 4 As shown, Figure 4 A schematic diagram of the lateral force distribution pattern based on the vibration mode combination during the update phase loading in this embodiment is shown.

[0149] Figure 4 (a) to Figure 4 (d) shows the lateral force distribution modes of the initial vibration modes of the structure in the four initial stages of the pushover process. The instantaneous vibration mode of the two update stages and the combined lateral force distribution mode The structural lateral force distribution patterns in the figure are all normalized with the top lateral force of the structure as 1. The j is 1, 2, 3, 4, and k is 0, 1, 2, which includes the initial stage, update stage 1, and update stage 2. Of course, in actual applications, update stage 1 can also be called the first update stage, the first update stage, the first loading stage, etc., and the other update stages k are also the same, which is not limited here.

[0150] As can be seen from the figure, during the overthrow process, the lateral force distribution mode of the structural vibration mode combination changes significantly with the increase of the displacement of the structure's vertex, that is, the degree of nonlinearity of the structure affects the lateral force distribution mode of the structural vibration mode combination. The standard earthquake action method provided by the present invention takes into account the update of the lateral force distribution mode of the structure during the overthrow process, which is conducive to accurately evaluating the seismic demand of the structure in the entire nonlinear process under the action of the earthquake, and improves the accuracy of the study of the structural seismic demand.

[0151] In this embodiment, based on the structural lateral force distribution mode update stage k, the structure vertex displacement after the loading of the structure in the kth update stage is obtained. Displace the structure vertices With the limit displacement u max For comparison, if the structure vertex displacement Less than or equal to the limit displacement u max , then update stage k = k + 1, and calculate the structure vertex displacement again If the structure vertex displacement Greater than the limit displacement u max Based on the instantaneous vibration mode combined lateral force distribution mode of the structure in the kth update stage obtained, the structural capacity spectrum curve is determined by calculation to obtain the structural target displacement u j In this embodiment, the limit displacement u max The maximum inter-story displacement angle of the structure is taken as 2%.

[0152] Based on the obtained structural target displacement u j , and the instantaneous vibration mode combination lateral force distribution mode of the structure in the kth update stage Calculate and determine the standard earthquake action F of the structure j .

[0153] The standard earthquake action F proposed by the present invention j It can better predict the inter-layer displacement angle of the structure under the action of earthquake. The traditional nonlinear static analysis method, namely the MPA method, the dynamic time history analysis method (NLRHA) and the standard earthquake action of the present invention are used to predict the inter-layer displacement angle of the structure under the action of earthquake as a comparative analysis to verify that the standard earthquake action of the present invention can more accurately determine the seismic demand of the structure.

[0154] like Figure 5 As shown, Figure 5 The structure target spectrum and the seismic influence coefficient curve determined by the selected ground motion in this embodiment are shown. Figure 5It can be seen that the mean value determined by the selected seismic motion is in good agreement with the structural target spectrum at the structural natural vibration period (1.678s), indicating that the selected seismic motion is more appropriate. In this example, the nonlinear dynamic time history analysis (NLRHA) of the structure was performed using finite element software such as Perform3D, and the selected seismic motion parameters are shown in Table 2.

[0155] like Figure 6 As shown, Figure 6 A schematic diagram of the comparison curve of the inter-story displacement angle of the structure of the present invention is shown. It can be seen from the figure that the inter-story displacement angle of the upper part of the structure determined by the MPA method is closer to the inter-story displacement angle of the upper part of the structure determined by the NLRHA, while the inter-story displacement angles of the middle and lower parts of the structure determined by the MPA are larger than the inter-story displacement angles of the middle and lower parts of the structure determined by the NLRHA. Among them, the inter-story displacement angle of the 4th floor of the structure determined by the MPA is 48.26% larger than that of the NLRHA. The inter-story displacement angle of the structure determined by the standard earthquake action proposed in the present invention is very close to the NLRHA.

[0156] Figure 7 The overall error comparison of the standard earthquake action and the MPA method in determining the interlayer displacement angle of the structure in this embodiment is shown. The overall error δ E Calculated by the following formula:

[0157]

[0158] In the formula, δ i-P is the maximum value of the response of each floor of the structure under MPA nonlinear static analysis, i = 1, 2, 3...Q; δ i-N It is the average value of the maximum response of each floor of the structure under the NLRHA method, i = 1, 2, 3...Q; here Q is the number of floors of the structure.

[0159] Depend on Figure 7 It can be seen that the overall error of the standard earthquake action in predicting the inter-layer displacement angle of the structure is within 5%, which is 64% lower than the overall error of the MPA method. The standard earthquake action provided by the present invention has a higher accuracy rate in determining the structural seismic demand and has more effective values.

[0160] Table 2 Earthquake parameters

[0161]

[0162] Figures 8 to 11 Another specific embodiment is provided to better explain the present method.

[0163] This embodiment provides a building structure, which adopts a 5×5 span 15-story reinforced concrete frame structure, with a structural column distance of 8m and a floor height of 3m. Figure 8 As shown, Figure 8 (a) shows a schematic plan view of the building structure in this embodiment, Figure 8 (b) shows a schematic elevation view of the building structure in this embodiment.

[0164] The building structure design intensity is 7 degrees, the seismic design group is the first group, the site category is the second category, and the dead load and live load applied to the structure floor are 5kN / m 2 and 2kN / m 2 , structural components and material information are shown in Table 3.

[0165] Table 3 Basic information of structural components and materials

[0166]

[0167] In this structure, the number of structural vibration modes is 3, and the third-order vibration mode pushover analysis in the same direction is performed on this structure to obtain the parameters of the elastic stage of this structure: the structural n-order vibration mode vector Structural mass m, structural vibration mode participation coefficient Structural spectral acceleration and mode combination coefficient

[0168]

[0169] According to the elastic stage parameters obtained above, the initial vibration mode combined lateral force distribution mode of the structure is obtained.

[0170] In this embodiment, according to the yielding of a batch of similar components of the structure, the updating stage of the structural lateral force distribution mode is divided to obtain the structural lateral force distribution mode updating stage k. Specifically, the lateral force is updated when a batch of similar frame beam components yield, and the lateral force is updated when a batch of similar frame column components yield. The updating stage k of the structural lateral force distribution mode is taken as 2. The lateral force of the structure changes from the initial stage to the updating stage 1 to the updating stage 2 during the overturning process. Based on the structural lateral force distribution mode updating stage k, the instantaneous vibration mode combined lateral force distribution mode of the structure in the kth updating stage is obtained. The j is 1, 2, 3, 4, and the k is 0, 1, 2, which includes the initial stage, the update stage 1 and the update stage 2.

[0171] In this embodiment, based on the structural lateral force distribution mode update stage k, the structure vertex displacement after the loading of the structure in the kth update stage is obtained. Displace the structure vertices With the limit displacement u max For comparison, if the structure vertex displacement Less than or equal to the limit displacement u max , then update stage k = k + 1, and calculate the structure vertex displacement again If the structure vertex displacement Greater than the limit displacement u max , then based on the instantaneous vibration mode combined lateral force distribution mode of the structure in the kth update stage obtained, the structural capacity spectrum curve is determined by calculation to obtain the structural target displacement u j In this embodiment, the limit displacement u max The maximum inter-story displacement angle of the structure is taken as 2%.

[0172] Based on the obtained structural target displacement u j , and the instantaneous vibration mode combination lateral force distribution mode of the structure in the kth update stage Calculate and determine the standard earthquake action F of the structure j .

[0173] The standard seismic action proposed in the present invention can better predict the inter-layer displacement angle of the structure under seismic action. The traditional nonlinear static analysis method, namely the MPA method, the dynamic time history analysis method (NLRHA) and the standard seismic action of the present invention are used to predict the inter-layer displacement angle of the structure under seismic action for comparative analysis.

[0174] like Fig. 9 As shown, Fig. 9 The structure target spectrum and the seismic influence coefficient curve determined by the selected ground motion in this embodiment are shown. Fig. 9 It can be seen that the mean value determined by the selected seismic motion is in good agreement with the structural target spectrum at the structural natural vibration period (2.52s), indicating that the selected seismic motion is more appropriate. In this example, the nonlinear dynamic time history analysis (NLRHA) of the structure was performed using finite element software such as Perform3D, and the selected seismic motion parameters are shown in Table 4.

[0175] like Fig.10 As shown, Fig.10 A schematic diagram of the comparison curve of the inter-story displacement angle of the structure of the present invention is shown. It can be seen from the figure that the inter-story displacement angle of the upper part of the structure determined by the MPA method is closer to the inter-story displacement angle of the upper part of the structure determined by the NLRHA, while the inter-story displacement angles of the middle and lower parts of the structure determined by the MPA are larger than the inter-story displacement angles of the middle and lower parts of the structure determined by the NLRHA. Among them, the inter-story displacement angle of the 5th floor of the structure determined by the MPA is 74.45% larger than that of the NLRHA. The inter-story displacement angle of the structure determined by the standard earthquake action proposed in the present invention is very close to the NLRHA.

[0176] Fig.11 The overall error comparison of the standard earthquake action and the MPA method in determining the interlayer displacement angle of the structure in this embodiment is shown. The overall error δ E Calculated by the following formula:

[0177]

[0178] In the formula, δi-P is the maximum value of the structure response of each floor under nonlinear static analysis, i = 1, 2, 3...Q; δ i-N is the average value of the maximum response of each floor of the structure under the NLRHA method, i = 1, 2, 3...Q;

[0179] Here Q is the number of floors of the structure.

[0180] Depend on Fig.11 It can be seen that the overall error of the standard earthquake action in predicting the inter-layer displacement angle of the structure is within 5%, which is 71% lower than that of the MPA method. The standard earthquake action provided by the present invention has a higher accuracy rate in determining the structural seismic demand and has more effective values.

[0181] Table 4 Earthquake parameters

[0182]

[0183] The present invention provides a method for determining standard seismic actions based on the entire process of structural nonlinearity. The method aims to address the problems that the lateral force distribution mode of the structure has inconsistent directions of lateral forces along floors corresponding to high-order vibration modes, the higher-order vibration modes have different degrees of influence on the lateral force distribution mode relative to the first vibration mode, and vibration mode parameters continue to change with the development of structural nonlinear behavior. The method takes into account the update of the lateral force distribution mode of the structure during the overthrow process based on the entire process of structural nonlinearity, and also takes into account the relative contribution and direction of action of each order vibration mode. Compared with traditional nonlinear static analysis methods, the method has higher accuracy in determining structural seismic demands, and compared with dynamic time-history analysis methods, the method has less calculation complexity and a simpler process, which is conducive to the prediction and determination of structural seismic demands.

[0184] It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as methods, systems or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0185] The present invention is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems) and computer program products according to the embodiments of the present invention. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions.

[0186] It should be noted that in the claims, any reference numerals between brackets should not be understood as limiting the claims. The word "comprising" does not exclude the presence of components or steps not listed in the claims. The word "one" or "an" preceding a component does not exclude the presence of multiple such components. The present invention can be implemented by means of hardware including several different components and by means of a suitably programmed computer. In addition, it should be noted that in the description of this specification, the description of the terms "one embodiment", "some embodiments", "embodiments", "examples", "specific examples" or "some examples" and the like refers to the specific features, structures, materials or characteristics described in conjunction with the embodiment or example included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples without contradiction.

[0187] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments after knowing the basic creative concept. Therefore, the claims should be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present invention.

[0188] Obviously, those skilled in the art can make various modifications and variations to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention should also include these modifications and variations.

Claims

1. A method for determining standard earthquake action based on the whole process of structural nonlinearity, characterized in that: The following steps are involved:

101. Perform n-order mode pushover analysis on the structure to obtain parameters of the structure in the elastic stage; 102. Calculate the obtained elastic stage parameters to obtain the initial vibration mode combined lateral force distribution mode of the structure 103. Update stage k based on the pre-built structural lateral force distribution pattern, and obtain the structural vertex displacement after the loading of the structure in the kth update stage is completed. According to the obtained structure vertex displacement Get the instantaneous vibration mode combined lateral force distribution mode of the structure in the kth update stage 104. Displace the structure vertices With the limit displacement u max For comparison: If the structure vertex displacement Greater than the limit displacement u max , execute step 105; Otherwise, update stage k=k+1 and execute step 103; 105. Based on the obtained instantaneous vibration mode combination lateral force distribution mode of the structure in the kth update stage Calculate and determine the structural capacity spectrum curve and obtain the structural target displacement u j ; 106. Combination of lateral force distribution modes based on the instantaneous vibration mode of the structure in the kth update stage and the structural target displacement u j , determine the standard earthquake action F of the structure by calculation j .

2. The method for determining the standard earthquake action according to claim 1, characterized in that: The standard earthquake action determination method further includes: Based on the structural standard earthquake action F determined by the calculation j , obtain the structure under standard earthquake action F j The structural seismic demand envelope value when acting.

3. The method for determining the standard earthquake action according to claim 1, characterized in that: Before step 101, the method further includes: According to the cumulative participation coefficient of the structural vibration mode mass, the number of vibration modes n of the n-order vibration mode is determined; The cumulative participation coefficient of the structural modal mass exceeds 90%; In step 101, the elastic phase parameters obtained include: Structural n-order vibration mode vector Structural mass m, structural vibration mode participation coefficient Structural spectral acceleration and mode combination coefficient 4. The method for determining the standard earthquake action according to claim 1, characterized in that: The step 102 specifically includes: 102a. Determine the initial lateral force distribution mode of the nth vibration mode of the structure; 102b. Combine the multiple n-th vibration mode initial lateral force distribution modes of the structure according to a pre-constructed combination method to obtain j initial vibration mode combined lateral force distribution modes.

5. The method for determining the standard earthquake action according to claim 1, characterized in that: The step 103 specifically includes: 103a. Determine the displacement of the structure at the kth update stage from the pushover to the structure vertex The first vibration mode vector of the structure 103b, according to the first vibration mode vector of the structure obtained Obtain the parameters of the nth vibration mode of the structure at the kth update stage; 103c. Acquire the instantaneous lateral force distribution mode of the nth vibration mode structure in the kth updating stage according to the acquired parameters of the nth vibration mode in the kth updating stage; 103d. According to the instantaneous lateral force distribution mode of the n-th vibration mode structure in the k-th update stage, multiple instantaneous lateral force distribution modes of the n-th vibration mode structure in the k-th update stage are combined according to a pre-constructed combination method to obtain j instantaneous vibration mode combined lateral force distribution modes of the structure in the k-th update stage.

6. The method for determining the standard earthquake action according to claim 5, characterized in that: The kth update stage parameters include: the kth update stage vibration mode vector Participation coefficient of the kth update stage Spectral acceleration at the kth update stage and the kth update stage mode combination coefficient 7. The method for determining standard earthquake action according to claim 1, characterized in that: The limit displacement u max is the maximum inter-story displacement angle of the structure, and the maximum inter-story displacement angle of the structure is 2%.

8. The method for determining standard earthquake action according to claim 1, characterized in that: The step 105 specifically includes: 105a. Based on the instantaneous vibration mode combined lateral force distribution mode of the structure in the kth update stage obtained, the instantaneous vibration mode combined lateral force distribution mode is obtained. Structural floor deformation at the kth update stage and floor shear 105b, according to the kth update stage structural floor deformation and floor shear Obtain the formula for the capability spectrum curve of the equivalent single-degree-of-freedom system; 105c, according to the displacement of the structure vertices Determine the instantaneous vibration mode combination lateral force distribution mode of the structure at the kth update stage The corresponding ductility coefficient of the equivalent single degree of freedom system 105d, according to the ductility coefficient of the equivalent single degree of freedom system at the kth update stage Determine the formula of the elastic-plastic demand spectrum curve of the equivalent single-degree-of-freedom system in the kth update stage; 105e. Determine the instantaneous vibration mode combination lateral force distribution mode according to the above-mentioned equivalent single-degree-of-freedom system capacity spectrum curve formula and the equivalent single-degree-of-freedom system elastic-plastic demand spectrum curve formula. The corresponding equivalent single-degree-of-freedom system target spectrum displacement S dj , based on the target spectrum displacement S of the equivalent single degree of freedom system dj The target displacement u of the structure is calculated j .

9. The method for determining the standard earthquake action according to claim 8, characterized in that: The formula of the equivalent single degree of freedom system capability spectrum curve is: is the spectral acceleration in the capacity spectrum curve of the equivalent single-degree-of-freedom system in the jth combination and the kth update stage; is the spectral displacement in the capacity spectrum curve of the equivalent single-degree-of-freedom system in the jth combination mode and the kth update stage; I is the unit vector, and T is the natural vibration period of the structure; The formula of the elastoplastic demand spectrum curve of the equivalent single degree of freedom system is: is the elastic spectral acceleration with a damping ratio of ξ; is the lateral force distribution mode combined with the instantaneous vibration mode of the jth combination mode The corresponding strength reduction factor; Based on the target spectrum displacement S of the equivalent single degree of freedom system dj The target displacement u of the structure is calculated j , the calculation formula is: you j =c j f j S dj 。 10. The method for determining standard earthquake action according to claim 1, characterized in that: The standard earthquake action F j The calculation formula is: Based on the standard earthquake action F j Calculate and obtain the instantaneous vibration mode and lateral force distribution mode of the structure Structural seismic demand S j , based on the structural seismic demand S j , obtain the total seismic response S of the structure; The total structural seismic response S is the structural seismic demand S j The envelope value of .

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