考虑土-桩筏基础-结构的共同作用的层间隔震结构地震响应

Seismic Response of Story Isolation Structure Considering Soil Pile Raft Foundation Structure Interaction

层间隔震结构是一种新型隔震体系,近年来其隔震性能受到各国学者关注。采用有限元软件ABAQUS建立了层间隔震结构三维整体空间模型,考虑地基土-桩筏基础-上部结构的共同作用(soil-structure interaction, SSI),进行地震作用下的非线性动力响应分析。研究了考虑SSI前后的层间隔震结构体系振动特性及动力响应,通过改变基础底部不同土层性质、不同桩长,探讨各因素对考虑SSI的层间隔震结构的影响规律。结果表明:不考虑SSI的层间隔震结构基底剪力、各层位移明显大于考虑SSI的情况;基底采用硬土层时的基底剪力、各层位移大于采用软土层时的情况;深桩基础相比浅桩基础的周期小、基底剪力、顶点位移、各层位移均增大。

Story isolation structure is a new type of isolation system.In recent years,its isolation performance has been concerned by scholars all over the world.A three-dimensional global spatial model of layered isolation structure was established by using the finite element software ABAQUS.Considering the soil-structure interaction(SSI)of the soil-pile-raft foundation and superstructure,the nonlinear dynamic response of the structure under seismic action was analyzed.The vibration characteristics and dynamic response of story isolation structure system before and after SSI were studied.The influence of various factors on the layer isolation structure considering SSI was discussed by changing the properties of different soil layers and different pile lengths at the bottom of the foundation.The results show that the base shear force and displacement of story without SSI are significantly greater than those with SSI;the base shear force and displacement of story with hard soil are greater than those with soft soil;the period of deep pile foundation is smaller than that of shallow pile foundation,and the base shear force,top displacement and displacement of story are increased.