Reaction spectrum reverse iteration algorithm with additional damping ratio

Abstract

The invention discloses a reaction spectrum reverse iteration algorithm of an additional damping ratio, relates to the technical field of constructional engineering, and aims to reversely calculate reasonable parameters of a damper and a connecting component from the final demand (namely, the additional damping ratio demand and the rigidity demand of a damping target) of a main body structure, and merge and iterate according to the model of a common damper product to obtain a response spectrum reverse iteration algorithm of the additional damping ratio. And compared with the traditional forward iteration, the efficiency of the reverse iteration algorithm is higher.

Description

Technical Field

[0001] The invention relates to the technical field of building engineering, and in particular to a response spectrum reverse iteration algorithm for adding a damping ratio. Background Art

[0002] When the main structure is basically elastic, there are two methods for the seismic calculation of displacement dampers: response spectrum iteration and time-history analysis. Among them, the time-history analysis method has great differences in structural response under different seismic waves, and there is a problem of mismatch between the dynamic stiffness of the damper calculated in the time history and the static stiffness used for response spectrum calculation. Therefore, its practical application is relatively small. Since the response spectrum iteration method does not require time-history wave selection, it is more suitable for the seismic calculation of displacement dampers than the time-history analysis method.

[0003] The commonly used response spectrum iteration method can be called the forward iteration algorithm, and the main process is as follows:

[0004] 1. The designer determines the layout and parameters of the damper based on experience;

[0005] 2. In the response spectrum model, the elastic parameters of the damper are used as the initial input conditions, and the additional damping ratio and additional stiffness of the damper to the structure under nonlinear conditions are obtained through multiple rounds of iterations;

[0006] 3. Determine whether the above calculation results meet the structural requirements. If they do, end the calculation;

[0007] 4. If the requirements are not met, adjust the damper layout and parameters according to the calculation results and perform the next round of iteration until the requirements are met.

[0008] The commonly used response spectrum iteration method has the following technical problems:

[0009] 1. It is difficult to infer the nonlinear performance of the damper through the initial elastic parameters, and the determination of the elastic parameters of the damper is heavily dependent on the designer's experience in shock absorption design.

[0010] 2. The damper iterates from the elastic state to the final nonlinear performance point. Due to the large difference, it needs to go through many calculation iterations of the overall model. For large models, the calculation time is long, and if the parameters are not selected properly, multiple rounds of trial calculation iterations are required, and the design efficiency is very low.

[0011] Therefore, it is necessary to provide a response spectrum inverse iteration algorithm with an additional damping ratio that can solve the above technical problems. Summary of the invention

[0012] The object of the present invention is to provide a response spectrum inverse iteration algorithm for adding damping ratio, which can solve the above technical problems.

[0013] The present invention is achieved in that:

[0014] A response spectrum inverse iteration algorithm for adding damping ratio includes the following steps:

[0015] Step 1: Determine the shock reduction target based on experience and main structure requirements;

[0016] Step 2: Input the shock reduction target and equivalent components into the model, and adjust the equivalent components so that the main structure meets the shock reduction target requirements;

[0017] Step 3: Read the internal force of the equivalent component under the earthquake condition, calculate the lateral stiffness of the equivalent component, and obtain the harmful deformation of the equivalent component through the internal force / lateral stiffness. The harmful deformation is used to characterize the force deformation of the energy dissipation component under the earthquake force;

[0018] Step 4: Based on the stress deformation of the energy dissipation component under the earthquake force calculated in step 3, estimate the deformation of the damper of the energy dissipation component under the rare earthquake, and determine the yield displacement of the damper based on the fatigue ductility coefficient of the damper;

[0019] Step 5: Divide the internal force of the equivalent component by the strengthening coefficient to estimate the yield force of the damper; determine the combined yield force of the damper based on the estimated yield force and the damper product model;

[0020] Step 6: Determine the cross-section of the connecting member of the energy dissipation component according to the stiffness and strength requirements;

[0021] Step 7: Take the yield force estimated in step 5 as the initial value of the calculated yield force, and determine the calculated yield force of the damper of the energy dissipation component in the model through iteration according to the internal force of the equivalent component, the stiffness of the connecting component determined in step 6, the yield displacement of the damper determined in step 4, and the post-yield stiffness ratio of the damper;

[0022] Step 8: Calculate the energy dissipation of each energy dissipation component and the structural strain energy to obtain the actual additional damping ratio;

[0023] Step 9: Combine the yield displacement of the damper determined in step 4 and the calculated yield force of the damper determined in step 7 to review the combined yield force of the damper in step 5;

[0024] Step 10: Calculate the ratio of the combined yield force of the damper in step 9 to the calculated yield force of the damper in step 7, and multiply the ratio by the stiffness of the equivalent component as the stiffness value of the equivalent component in the next iterative calculation;

[0025] Step 11: According to the additional damping ratio in step 8 and the stiffness value of the equivalent component in step 10, repeat steps 3 to 10 until the difference between the additional damping ratios in the previous and next steps and the difference in the calculated yield force of each equivalent component are no more than 5%.

[0026] In the step 1, the shock absorption targets include additional damping ratio, displacement angle, and component reinforcement.

[0027] In the step 2, the equivalent components in the model simulate the energy dissipation components in the main structure, and the cross-sectional dimensions of the equivalent components are adjusted so that the stiffness of the equivalent components meets the performance requirements of the main structure.

[0028] The equivalent component is a support or a column or a beam, and the energy dissipation component is composed of a damper and a connecting component. The secant stiffness of the energy dissipation component refers to the effective stiffness of the equivalent component after yielding, that is, the sum of the series stiffness of the effective stiffness of the damper and the stiffness of the connecting component.

[0029] In step 5, the enhancement coefficient is related to the type and connection form of the damper, and the value range of the enhancement coefficient is 1.0 to 1.1.

[0030] In step 7, the iterative process of calculating the yield force is: the estimated yield force is used as the initial value F of the yield force y0 , the error between the estimated yield force and the calculated yield force is less than the allowable value, then the calculation is considered to meet the requirements. This is an iterative process. y0 The next yield force F is calculated from the yield displacement of the damper, the post-yield stiffness ratio, and the stiffness of the connecting components. y1 , use F y1 Calculate the next yield strength F y2 , and repeat this process until the n-1th calculation of the yield force F yn-1 With the nth calculated yield force F yn The error does not exceed 5%.

[0031] When the damper and the connecting member are modeled separately, the equivalent stiffness of the damper + the elastic stiffness of the connecting member are used to perform subsequent iterative calculations starting from the second round of iteration.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] 1. Since the present invention adopts a reverse iterative algorithm, the influence of the damper on the main structure is reflected in the additional damping ratio and the additional stiffness. In the response spectrum model, the estimated additional damping ratio and equivalent components are used for reverse iterative calculation, which is more in line with the design habits of structural designers.

[0034] 2. The present invention can quickly estimate the output and deformation of the damper and the yield force, yield displacement and other parameters of the damper adapted to the main structure requirements according to the internal force and stiffness of the equivalent component, and further calculate the corresponding damping energy consumption.

[0035] 3. Since the present invention starts iteration from the final reaction of the structure, the number of iterations required by this iterative method will be less than that of the forward algorithm. The iteration efficiency of the reverse iterative algorithm can be as high as 50% to 100% compared with the forward iterative algorithm.

[0036] 4. The present invention can determine whether further calculation iterations are required through multiple control parameters in the first round of iterations, avoiding the situation in the forward algorithm where all multiple rounds of iterations must be completed before determining whether the parameters are reasonable. This is specifically manifested in the following two aspects:

[0037] (1) At the beginning of the first round of iteration, the ratio of the harmful deformation of the equivalent components to the floor deformation can be used to preliminarily determine whether the position and secant stiffness of the energy dissipation components are reasonable, thereby determining whether the next step of calculation is needed. If the proportion of unreasonable energy dissipation components is large, it is possible to consider terminating the iterative calculation and adjusting the layout and parameters of the equivalent components.

[0038] (2) The additional damping ratio obtained after the first round of iteration will not be very different from the final value. When the difference between the additional damping ratio obtained after the first round of iteration and the additional damping ratio of the damping target is large, it can be considered to terminate the iteration and adjust the layout and parameters of the equivalent components. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 It is a schematic diagram of an equivalent component and an energy dissipation component in a model of a response spectrum reverse iteration algorithm for adding a damping ratio of the present invention;

[0040] Figure 2 It is a schematic diagram of another equivalent component and energy dissipation component in the model of the response spectrum reverse iteration algorithm of the additional damping ratio of the present invention;

[0041] Figure 3 is the force-displacement curve of the metal damper of the response spectrum reverse iteration algorithm of the present invention with additional damping ratio;

[0042] Figure 4 is the force-displacement curve calculated by the first and nth iterations of the response spectrum reverse iteration algorithm of the present invention with the added damping ratio;

[0043] Figure 5 It is a calculation diagram of the energy dissipation area of ​​the damper of the response spectrum reverse iteration algorithm of the present invention with additional damping ratio;

[0044] Figure 6It is a schematic diagram comparing the distance between the initial point and the target point in the response spectrum reverse iteration algorithm (ie, inverse algorithm) of the present invention and the distance between the initial point and the target point in the traditional forward iteration algorithm (ie, forward algorithm).

[0045] In the figure, 1 is an equivalent component, 2 is a main structure, 301 is a damper, and 302 is a connecting component. DETAILED DESCRIPTION

[0046] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0047] A response spectrum inverse iteration algorithm for adding damping ratio includes the following steps:

[0048] Step 1: Determine the shock absorption target based on experience and main structure requirements.

[0049] The shock absorption targets include additional damping ratio, displacement angle, component reinforcement, etc.

[0050] Please see attached Figure 1 and attached Figure 2 , Step 2: Input the shock absorption target (additional damping ratio) and equivalent component 1 into the model, and adjust the equivalent component 1 so that the main structure 2 meets the requirements of the shock absorption target.

[0051] The equivalent component 1 in the model simulates the energy dissipation component in the main structure 2, and the cross-sectional size of the equivalent component 1 is adjusted so that the stiffness of the equivalent component is equal to the secant stiffness of the energy dissipation component.

[0052] The equivalent component 1 can be a support, a column, a beam, etc. The energy dissipation component is composed of a damper 301 and a connecting component 302. The secant stiffness of the energy dissipation component refers to the effective stiffness of the equivalent component after yielding, that is, the sum of the series stiffness of the effective stiffness of the damper 301 and the stiffness of the connecting component 302.

[0053] As a preferred embodiment, in the attached Figure 1 In the figure, the equivalent component 1 is a steel support with an inverted V-shaped structure, the energy dissipation component is composed of a pair of connecting components 302 arranged in an inverted V shape and a damper 301 connected between the top of the pair of connecting components 302 and the main structure 2, and the arrangement form and position of the energy dissipation component are determined according to the arrangement form and position of the equivalent component 1.

[0054] As another preferred embodiment, in the attached Figure 2 In the figure, the equivalent component 1 is a steel column, the connecting component 302 of the energy dissipation component includes an upper connecting wall and a lower connecting wall, the damper 301 is connected between the upper connecting wall and the lower connecting wall, and the arrangement form and position of the energy dissipation component are determined according to the arrangement form and position of the equivalent component 1.

[0055] Step 3: Read the internal force of equivalent component 1 under earthquake conditions, calculate the lateral stiffness of equivalent component 1, and obtain the harmful deformation of equivalent component 1 through internal force / lateral stiffness. The harmful deformation is used to characterize the force deformation of the energy dissipation component under earthquake force.

[0056] The calculation of harmful deformation in the first step does not need to be iterated. The ratio of harmful deformation to floor deformation can be used to preliminarily judge whether the layout position of the energy dissipation component or the secant stiffness of the energy dissipation component is reasonable. If it is unreasonable, consider interrupting the iteration and adjusting the position of the equivalent component 1 or the secant stiffness of the energy dissipation component.

[0057] Step 4: Based on the stress deformation of the energy dissipation component under seismic force calculated in step 3, estimate the deformation of the damper 301 of the energy dissipation component under rare earthquakes (large earthquakes), and determine the yield displacement of the damper 301 based on the fatigue ductility coefficient of the damper 301.

[0058] The deformation of the damper 301 under a rare earthquake can be estimated by the harmful deformation of the energy dissipation component under a small / moderate earthquake. According to experience, the deformation of the damper 301 under a large earthquake is ≈ 2.5 to 3 times the harmful deformation of the energy dissipation component under a moderate earthquake.

[0059] The fatigue ductility coefficient of the damper 301 represents the multiple relationship between the design displacement and the yield displacement, wherein the design displacement refers to the displacement value reached by the damper 301 under a rare earthquake, and this data is used as the basis for detecting whether the damper 301 meets the requirements of the specification. Here, by reverse calculation, the deformation of the damper 301 under a rare earthquake estimated above is divided by the fatigue ductility coefficient to obtain the yield displacement of the damper 301. It should be noted that the fatigue ductility coefficient of the damper 301 is greatly affected by the material, and there are also large differences between the dampers 301 of different suppliers. It can be calculated according to the actual design requirements and the damper 301 materials actually used.

[0060] Step 5: Divide the internal force of the equivalent component 1 by the reinforcement coefficient to estimate the yield force of the damper 301. The reinforcement coefficient is related to the type and connection form of the damper 301, and the value range of the reinforcement coefficient is generally 1.0 to 1.1. Determine the combined yield force of the damper 301 based on the estimated yield force and the product model of the damper 301.

[0061] Taking the metal damper as an example, the force-displacement curve of the metal damper is shown in the attached figure. Figure 3As shown, the post-yield stiffness ratio β is a number not less than 0, K1=K0×β, wherein K1 is the post-yield stiffness of the damper 301, and K0 is the elastic stiffness of the damper 301. After the damper 301 yields, the output of the damper 301 will continue to rise, so the actual output of the damper 301 after yielding in the model is greater than the yield force of the damper 301. Therefore, when estimating the yield force, the internal force of the equivalent component 1 in the model needs to be appropriately reduced according to the damper output after yielding. Therefore, the yield force is estimated by dividing by the reinforcement coefficient with a value between 1.0 and 1.1.

[0062] Step 6: Determine the cross-section of the connecting member 302 of the energy dissipation component according to the stiffness and strength requirements.

[0063] Strength requirement refers to the elasticity that the connection member 302 needs to maintain under rare earthquakes (determined according to relevant specifications), and stiffness requirement refers to the deformation of the connection member 302 should not be too large under the specified performance target, so as to ensure that the deformation of the energy dissipation component is more concentrated on the damper 301. For example, Article 7.3.3 of the Technical Code for Energy Dissipation and Shock Reduction of Buildings JGJ 297-2013 clearly states that the effective stiffness of the connection member should not be less than twice the effective stiffness of the damper.

[0064] Step 7: Use the yield force estimated in step 5 as the initial value for calculating the yield force. According to the internal force of the equivalent component 1, the stiffness of the connecting component 302 determined in step 6, the yield displacement of the damper 301 determined in step 4, and the post-yield stiffness ratio of the damper 301 (determined by the type of the damper 301), determine the calculated yield force of the damper 301 of the energy dissipation component in the model through iteration (without the need for overall model calculation).

[0065] Since there must be a certain error between the combined yield force of the damper 301 and the calculated yield force corresponding to the energy dissipation component in the model, the calculated yield force is used as the basis for the subsequent calculation of the additional damping ratio.

[0066] The iterative process for calculating the yield force is: Figure 4 , the estimated yield stress is used as the initial value for calculating the yield stress F y0 The error between the estimated yield force and the calculated value of the yield force (point A) is less than the allowable value (generally considered not to exceed 5%), then the calculation is considered to meet the requirements. This is an iterative process. y0 The yield displacement and post-yield stiffness ratio of the damper 301 and the stiffness of the connecting member 302 are used to calculate the next yield force F y1 , use F y1 Calculate the next yield strength F y2 , and repeat this process until the n-1th calculation of the yield force F yn-1With the nth calculated yield force F yn The error does not exceed 5%.

[0067] Step 8: Calculate the energy dissipation of each energy dissipation component and the structural strain energy to obtain the actual additional damping ratio.

[0068] The calculation formula of damper energy dissipation and damping ratio is from Article 12.3.4 of Code for Seismic Design of Buildings GB50011-2010:

[0069] Where: a —Additional effective damping ratio of energy dissipation and shock absorption structure; W cj —Expected inter-story displacement of the jth energy dissipation component in the structure Δ μ j The energy consumed in one reciprocating cycle is the area of ​​the hysteresis curve; W s —The total strain energy of the structure under the expected displacement set by the energy dissipation component.

[0070] Please see attached Figure 5 , taking the metal damper as an example, the energy dissipation area of ​​a single metal damper is calculated according to the parallelogram law, and the specific calculation formula of the damper energy dissipation is as follows:

[0071] W cj =4(F dy >u dmax "F max >u dy )(>u dmax >>u dy )

[0072] Where: W Cj —Energy consumption of a single damper; F dy —Damper yield force; △u y —Damper yield displacement; F max —actual output of damper; u dmax —Actual displacement of the damper.

[0073] Its structural strain energy:

[0074] Where: F i —Standard value of horizontal earthquake action on floor i; u i —Average total displacement of floor i (floor centroid displacement).

[0075] The calculation formula of the effective stiffness of the damper is: K eff =F max / Δu dmax .

[0076] The calculation of the energy dissipation component's energy consumption and the structural strain energy is a conventional calculation method in the art and will not be described in detail here. The actual additional damping ratio can be obtained based on the energy dissipation component's energy consumption and the structural strain energy.

[0077] Step 9: Based on the yield displacement of the damper 301 determined in step 4 and the calculated yield force of the damper 301 determined in step 7, the combined yield force of the damper 301 in step 5 is reviewed.

[0078] When the difference between the estimated yield force and the merged yield force in step 5 is large, or the post-yield stiffness ratio of the energy dissipation component is relatively large and the damper 301 enters the plastic state to a deep extent, it is possible that the calculated yield force and the merged yield force in step 7 are quite different. At this time, it may be necessary to review and adjust the merged yield force based on the calculated yield force.

[0079] Step 10: Calculate the ratio of the combined yield force of the damper 301 in step 9 to the calculated yield force of the damper 301 in step 7, and multiply the ratio by the stiffness of the equivalent component 1 as the stiffness value of the equivalent component 1 in the next iterative calculation.

[0080] Step 11: According to the additional damping ratio in step 8 and the stiffness value of the equivalent component 1 in step 10, repeat steps 3 to 10 until the difference between the additional damping ratios in the previous and next steps and the difference between the calculated yield forces of each equivalent component 1 are no more than 5%.

[0081] The calculated yield force of the damper 301 and the calculated yield force of the equivalent component 1 are in a series relationship, and the calculated yield force of the damper 301 is equal to the calculated yield force of the equivalent component 1.

[0082] If the damper 301 and the connecting member 302 are modeled separately, the subsequent iterative calculation can also be performed in the form of equivalent stiffness of the damper 301 + elastic stiffness of the connecting member 302 .

[0083] The present invention starts from the final requirements of the main structure 2 (the additional damping ratio requirements and stiffness requirements of the shock absorption target), reversely calculates the reasonable parameters of the damper 301 and the connecting member 302, and performs merge iteration according to the commonly used damper product models, that is, the reverse iteration algorithm, which is more efficient than the traditional forward iteration, mainly because:

[0084] 1. The influence of the damper 301 on the main structure 2 is reflected in two aspects: additional damping ratio and additional stiffness. Using the estimated additional damping ratio and equivalent component 1 in the response spectrum model is more in line with the design habits of structural designers.

[0085] 2. According to the internal force and stiffness of the equivalent component 1, the output and deformation of the damper 301 and the yield force, yield displacement and other parameters of the damper 301 adapted to the requirements of the main structure 2 can be quickly estimated, and the corresponding damping energy consumption can be further calculated.

[0086] 3. Since the iteration starts from the final reaction of the main structure 2, that is, reverse iteration, please refer to the attached Figure 6 The reverse iteration algorithm sets the initial point when the target point is known. The initial point is usually close to the target point, while the target point of the forward iteration algorithm is unknown, so the yield point is far from the target point. Therefore, the reverse iteration algorithm requires fewer iterations than the forward iteration algorithm. According to statistics, the iteration efficiency of the reverse iteration algorithm can be 50% to 100% higher than that of the forward iteration algorithm.

[0087] In the first round of reverse iterative calculation, the parameters can be used to determine whether further calculation iterations are needed, thus avoiding the problem that the parameters can only be judged whether they are reasonable after all the multiple rounds of iterations in the forward iterative algorithm are completed. This is specifically manifested in the following two aspects:

[0088] (1) At the beginning of the first round of iteration, the ratio of the harmful deformation of equivalent component 1 to the floor deformation can be used to preliminarily determine whether the position and secant stiffness of the energy dissipation component are reasonable, thereby determining whether the next step of calculation is needed. If the proportion of unreasonable energy dissipation components is large, it can be considered to terminate the iterative calculation and adjust the layout and parameters of the equivalent components.

[0089] (2) The difference between the additional damping ratio obtained after the first round of iteration and the additional damping ratio in the damping target will not be very large. When the difference between the additional damping ratio obtained after the first round of iteration and the additional damping ratio in the damping target is large, it is also possible to consider terminating the iteration.

[0090] Example 1, in a certain construction project, the main structure 2 includes 10 floors above ground, the first floor has a floor height of 5.1m, and the 2nd to 10th floors have a floor height of 4.5m. 65.0×28.2m, and the building area is approximately 18,330 square meters. The main structure 2 adopts a steel frame structure, and the seismic resistance level requirement is level 2, and the performance target is: medium earthquake 1 / 200; large earthquake 1 / 80; 8 degrees 0.2g, group 2, category III, Tg=0.55s, the cross-section of the frame column is 700x800x38, the cross-section of the frame beam is H650x300x20x30, and a support shear type metal damper (abbreviated as: support type MD) is adopted, and the reverse iteration method of the present invention is used for trial calculation.

[0091] Step 1: Determine the performance target: medium earthquake displacement angle 1 / 200 (Class II), additional damping ratio of the seismic reduction target, etc. Use the contribution of the damper to controlling the floor deformation to temporarily estimate the additional damping ratio of the seismic reduction target, taking 4%.

[0092] In the original uncontrolled case, the maximum displacement angle of the model is 1 / 155, 1 / 134, which does not meet the requirement of 1 / 200, and the problem of about 30% displacement angle needs to be solved.

[0093] Step 2: When designing the model, input the additional damping ratio and equivalent component of the shock absorption target into the model, and adjust the cross-section of the equivalent component 1 so that the main structure meets the shock absorption target requirements.

[0094] (1) Input equivalent components: replace the steel support MD with a common support + rigid rod, where the rigid rod represents the damper 301 and the height of the rigid rod = damper height / 2 + beam height / 2.

[0095] (2) Input the additional damping ratio of the seismic reduction target: Set the additional damping ratio to be uniform for the entire building in the model.

[0096] (3) Adjust the cross section of equivalent component 1 through the model until the displacement angle, reinforcement, etc. are appropriate.

[0097] Step 3: Read the internal force of equivalent component 1 under earthquake conditions, calculate the lateral stiffness of equivalent component 1, and obtain the harmful deformation of equivalent component 1 through internal force / lateral stiffness.

[0098] According to statistics, the calculated values ​​of harmful deformation of the damper 301 are not small, indicating that the location of the damper is suitable.

[0099] Step 4: Harmful deformation at the root The deformation of the damper 301 under a rare earthquake is estimated in step 3, and the yield displacement of the damper 301 is determined based on the fatigue ductility coefficient of the damper 301.

[0100] According to experience, the deformation of the damper 301 under a large earthquake is ≈ 2.5 to 3 times the harmful deformation of the energy dissipation component under a moderate earthquake. Initial estimated yield displacement: The estimated displacement angle of the floor under a large earthquake is about 1 / 100, the ratio of the harmful deformation of the damper 301 to the floor deformation is 80%, the ductility coefficient of the damper 301 is 30 times, the damper yield displacement = 4500 / 100*0.8 / 30 = 1.2mm, the first floor height is higher, the yield displacement is 1.5mm, the displacement angle of the upper floor is smaller, and the yield displacement is 1.0mm. The specific calculation process values ​​are shown in Table 1:

[0101] Table 1

[0102]

[0103]

[0104] When the actual yield displacement (based on the previous estimated value) is greater than the minimum yield displacement, the requirements are met and no further adjustments are required.

[0105] Step 5: According to the post-yield stiffness ratio of the damper 301, the internal force of the equivalent component 1 is divided by the strengthening coefficient 1.1 as the estimated yield force. Combined with the yield displacement determined in step 4, the combined yield force of the damper 301 is obtained according to the commonly used product models, as shown in Table 2:

[0106] Table 2:

[0107]

[0108]

[0109] Step 6: According to the specification requirements, total deformation / support deformation ≥ 3. In this embodiment, the stiffness and strength requirements are set as: total deformation / support deformation> 4. The stiffness requirement is converted into deformation requirement to determine the cross-section of the connecting member 302, as shown in Table 3:

[0110] Table 3

[0111]

[0112] Step 7: Use the yield force estimated in step 5 as the initial value for calculating the yield force. According to the internal force of the equivalent component 1, the stiffness of the connecting component 302 determined in step 6, the yield displacement of the damper 301 determined in step 4, and the post-yield stiffness ratio of the damper 301 (determined by the type of the damper 301), determine the calculated yield force of the damper 301 of the energy dissipation component in the model through iteration (without the need for overall model calculation).

[0113] Step 8: Calculate the energy consumption of each energy dissipation component and the structural strain energy to obtain the actual additional damping ratio. The actual calculated additional damping ratio is: X-direction: 3.6%; Y-direction: 4.1%, which is consistent with the additional damping ratio of 4% of the shock absorption target.

[0114] Step 9: Based on the yield displacement of the damper 301 determined in step 4 and the calculated yield force of the damper 301 determined in step 7, the combined yield force of the damper 301 in step 5 is reviewed.

[0115] Step 10: Calculate the ratio of the combined yield force of the damper 301 in step 9 to the calculated yield force of the damper 301 in step 7, and multiply the ratio by the stiffness of the equivalent component 1 as the stiffness value of the equivalent component 1 in the next iterative calculation.

[0116] Step 11: According to the additional damping ratio in step 8 and the stiffness value of the equivalent component 1 in step 10, repeat steps 3 to 10. After three iterations, the basic convergence is achieved. The difference in the additional damping ratio between the previous and next steps and the difference in the calculated yield force of each equivalent component 1 are approximately 1.8%, which is no more than 5%. The iteration ends.

[0117] The above are only preferred embodiments of the present invention and are not intended to limit the scope of protection of the invention. Therefore, any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A response spectrum inverse iteration algorithm for adding damping ratio, characterized by: The following steps are involved: Step 1: Determine the shock reduction target based on experience and main structure requirements; Step 2: Input the seismic reduction target and equivalent components (1) into the model, and adjust the equivalent components (1) so that the main structure (2) meets the seismic reduction target requirements; Step 3: Read the internal force of the equivalent component (1) under the earthquake condition, calculate the lateral stiffness of the equivalent component (1), and obtain the harmful deformation of the equivalent component (1) through the internal force / lateral stiffness, wherein the harmful deformation is used to characterize the force deformation of the energy dissipation component under the earthquake force; Step 4: according to the stress deformation of the energy dissipation component under the earthquake force calculated in step 3, the deformation of the damper (301) of the energy dissipation component under the rare earthquake is estimated, and the yield displacement of the damper (301) is determined according to the fatigue ductility coefficient of the damper (301); Step 5: Divide the internal force of the equivalent component (1) by the strengthening coefficient to estimate the yield force of the damper (301); determine the combined yield force of the damper (301) based on the estimated yield force and the product model of the damper (301); Step 6: Determine the cross section of the connecting member (302) of the energy dissipation component according to the stiffness and strength requirements; Step 7: using the yield force estimated in step 5 as the initial value of the calculated yield force, and determining the calculated yield force of the damper (301) of the energy dissipation component in the model through iteration according to the internal force of the equivalent component (1), the stiffness of the connecting component (302) determined in step 6, the yield displacement of the damper (301) determined in step 4, and the post-yield stiffness ratio of the damper (301); Step 8: Calculate the energy dissipation of each energy dissipation component and the structural strain energy to obtain the actual additional damping ratio; Step 9: combining the yield displacement of the damper (301) determined in step 4 and the calculated yield force of the damper (301) determined in step 7, and checking the combined yield force of the damper (301) in step 5; Step 10: Calculate the ratio of the combined yield force of the damper (301) in step 9 to the calculated yield force of the damper (301) in step 7, and multiply the ratio by the stiffness of the equivalent component (1) as the stiffness value of the equivalent component (1) in the next iterative calculation; Step 11: According to the additional damping ratio in step 8 and the stiffness value of the equivalent component (1) in step 10, repeat steps 3 to 10 until the difference between the additional damping ratios in the previous and next steps and the difference in the calculated yield force of each equivalent component (1) are no more than 5%.

2. The response spectrum inverse iteration algorithm of the additional damping ratio according to claim 1 is characterized by: In the step 1, the shock absorption targets include additional damping ratio, displacement angle, and component reinforcement.

3. The response spectrum inverse iteration algorithm of the additional damping ratio according to claim 1 is characterized by: In the step 2, the equivalent component (1) in the model simulates the energy dissipation component in the main structure (2), and the cross-sectional dimensions of the equivalent component (1) are adjusted so that the stiffness of the equivalent component meets the performance requirements of the main structure (2).

4. The response spectrum inverse iteration algorithm of the additional damping ratio according to claim 3 is characterized by: The equivalent component (1) is a support or a column or a beam, and the energy dissipation component is composed of a damper (301) and a connecting component (302). The secant stiffness of the energy dissipation component refers to the effective stiffness of the equivalent component after yielding, that is, the sum of the series stiffness of the effective stiffness of the damper (301) and the stiffness of the connecting component (302).

5. The response spectrum inverse iteration algorithm of the additional damping ratio according to claim 1 is characterized by: In the step 5, the enhancement coefficient is related to the type and connection form of the damper (301), and the value range of the enhancement coefficient is 1.0 to 1.

1.

6. The response spectrum inverse iteration algorithm of the additional damping ratio according to claim 1 is characterized by: In step 7, the iterative process of calculating the yield force is: the estimated yield force is used as the initial value F of the yield force y0 , the error between the estimated yield force and the calculated yield force is less than the allowable value, then the calculation is considered to meet the requirements. This is an iterative process. y0 The next yield force F is calculated from the yield displacement and post-yield stiffness ratio of the damper (301) and the stiffness of the connecting member (302). y1 , use F y1 Calculate the next yield strength F y2 , and repeat this process until the n-1th calculation of the yield force F yn-1 With the nth calculated yield force F yn The error does not exceed 5%.

7. The response spectrum inverse iteration algorithm of the additional damping ratio according to claim 6 is characterized by: When the damper (301) and the connecting member (302) are modeled separately, the equivalent stiffness of the damper (301) + the elastic stiffness of the connecting member (302) are used to perform subsequent iterative calculations starting from the second round of iteration.

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