变截面桩基础体系高层建筑结构的地震响应  

Seismic response of high-rise structures by different foundation systems

作　　者：钱德玲[1] 李辉[1] 卢文胜[2] 李健全[1] 夏京[1] 

机构地区：[1]合肥工业大学土木与水利工程学院,安徽合肥230009 [2]同济大学土木工程防灾国家重点实验室,上海200092

出　　处：《岩土工程学报》2011年第1期98-103,共6页Chinese Journal of Geotechnical Engineering

基　　金：国家自然科学基金项目(4077217150278030);安徽省自然科学基金项目(050450402)

摘　　要：基于振动台模型试验,采用大型软件MARC进行了数值仿真试验,再现了在地震作用下桩基–结构相互作用体系的动力响应。研究结果表明:基础类型变化对高层建筑结构产生的变形影响较大,桩基–结构相互作用体系中上部结构的最大层间剪力和倾覆力矩等都比刚性地基上结构体系的要小,桩基–结构体系中相当一部分地震能量通过支盘扩散到土层中,减小了上部结构的变形能。而刚性地基上结构体系中相当一部分的地震能量则转化为上部结构的变形能,导致结构损伤较大。同时,振动台试验和数值仿真结果表明:支盘桩结构体系的阻尼能较大,能够有效地提高基础和结构体系的抗震和减震能力,降低上部结构在地震作用下的地震响应,对抵御地震、减少地震破坏具有十分重要的意义。Dynamic response of pile foundation-structure interaction is reproduced under earthquakes in the shaking table model tests and numerical simulation tests using software MARC.The results show that the effect of deformation of high-rise structures is large because of changed pile-type.The most shear force and overturning moment of high-rise structure in squeezed branch pile interaction system are smaller than those in straight pile interaction system.The deformation energy of the structure is reduced on account of considerable seismic energy in the interaction system of squeezed branch piles and is diffused to the soil through the branch or disk,while considerable seismic energy in the interaction system of straight piles and is converted into deformation energy of the structure,resulting in greater structural damage.At the same time,the results of shaking table tests and numerical simulation show that the squeezed branch pile-foundation has more damping energy,effectively enhances seismic capability of the structure system,and reduces seismic response of the structure under earthquakes.The study is of great significance to the reduction of earthquake damage.

关 键 词：振动台试验 动力相互作用 支盘桩 抗震减灾 数值仿真 

分 类 号：TU473.1[建筑科学—结构工程]