| RC frame structure is prone to layer yield failure mode during earthquake.With limited energy dissipation capacity,it is easy to lead to the overall collapse of a structure.Therefore,to control structural failure modes,different vibration control technologies emerge as the times require.Although these vibration control techniques can control structural seismic damage degree,they have limited effect in controlling the deformation pattern of the structure,reducing structural residual deformation,and improving the speed of post-seismic reconstruction.Thus,how to ensure that buildings achieve the expected damage pattern under seismic action has been the direction of continuous exploration by researchers.However,the frame-rocking wall structure can control structural lateral deformation mode via the rocking vibration of the rocking wall.Therefore,the expected overall damage mechanism can be achieved by reducing the probability of structural damage concentration caused by the randomness of earthquake and the uncertainty of structural performance.Based on this,a RC frame-rocking wall damping structure is proposed by comprehensively utilizing the structural advantages of rocking wall structure and damping principle of passive control technology.Then,the seismic response and seismic robustness of the frame structure model and the frame-rocking wall damping structure model were systematically analyzed by shaking table scaled model test,numerical simulation,and theoretical analysis under the action of EL Centro wave,Taft wave,and Artificial wave with different intensities.Therefore,the shock absorption effect of the frame-rocking wall damping structure under earthquake action can be evaluated in this way.The main research contents and results are as follows.(1)To realize the connection between the model structures and the shaking table,a rigid base that can realize different foundation settlement requirements is manufactured,and a method and device for connecting components with different material properties are designed.In addition,a type of simple connection structure with the characteristics of economical and practical,energy consumption and easy replacement is designed for the special performance requirements of the frame-rocking wall structure.Then the whole set of the invented device was applied to the shaking table test for experimental research.(2)Based on the similarity theory,two 1/10 scale model of frame structure and frame-rocking wall damping structure were designed and manufactured to study the shock absorption effect of the frame-rocking wall damping structure under earthquake actions.The dynamic characteristics and response of the two structural models under different fortification intensities(7 degrees and8 degrees)were detailedly analyzed by shaking table tests.The results show that there is an obvious relative displacement between the rocking wall damping device and the frame main structure,thus,the energy stored in the substructure can be dissipated by various ways,attenuating the dynamic response of the main structure effectively.Besides,the damping effect becomes more significant with the increase of earthquake intensity,and the floor peak acceleration can reach 2%-40%.(3)The damage suppression mechanism and lateral deformation control effect of framerocking wall damping structure under different earthquakes are studied through the damage index,macroscopic failure mode,and dynamic response time curve.The results show that the rocking wall damping system can effectively play its advantages of rocking vibration,increasing the heterogeneous vibration effect with the main structure.Therefore,the deformation distribution of each floor is more uniform and the residual displacement of the frame is smaller.In addition,the seismic energy can be transferred and dispersed to the upper floors through the energy exchange of each floor.This not only postpones the damage process of the main structure,delaying the time point at which the maximum displacement peak occurs by 0.39 s,0.32 s and 0.80 s,respectively,but also reduces the probability of layer yield failure caused by local damage accumulation,showing the overall yield failure characteristics.(4)By summarising the factors affecting the accuracy of the finite element model and the theoretical analysis,the specific analysis method and the relevant basis for the model accuracy control are given in this paper.Subsequently,the nonlinear dynamic analysis of the finite element model was carried out by using the finite element software ABAQUS,and the shaking table model test was restored by numerical simulation method according to the similarity relationship.Then,the scientific validity of the numerical simulation method and the reliability of the finite element model accuracy control for the frame-rocking wall damping structure were verified by comparing the acceleration response,displacement response,and structural damage of calculation results and test results.On this basis,it provides a strong basis for enriching and supplementing the research content.(5)Based on the Lagrangian equation,the differential equations of motion and damping mechanism of the frame-rocking wall damping structure in single-degree-of-freedom and multidegree-of-freedom systems are deduced and analyzed,respectively.The similarities and differences between the rocking wall damping system and the classical vibration control technology,namely the tuned mass damper,are discussed under different damping ratios and mass ratios of the substructure,providing a theoretical basis for proving the effectiveness of the framerocking wall damping structure.Then,the improved multi-population genetic algorithm is used to conduct multivariate parallel search for the optimal solution of the transfer function derived from the multi-degree-of-freedom systems.Then,the frame-rocking wall damping structure with optimized design is compared with the traditional TMD system,indicating that the frame-rocking wall damping structure has a more stable and effective overall damping effect.Therefore,the effectiveness of the optimization algorithm can provide a convenient and effective method for the complex vibration design of the frame-rocking wall damping structure.This paper has 73 figures,19 tables and 197 references. |
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