CAJ | 학술논문

进行了可液化土-高层结构地震相互作用的振动台试验,试验采用柔性容器以减小边界影响,采用饱和砂土作为模型土.试验中再现了液化场地土中高层结构的震害现象.得出的主要规律有:相互作用体系的振型曲线与刚性地基上结构的振型曲线明显不同;随着振动次数的增加,体系的频率降低,阻尼比增大;砂土对地震动可起滤波和隔震作用;当最初加速度峰值到达前,砂土层中的孔压比存在负值;震后土中孔隙水压力不一定随振动的停止而立即开始消散,在短期内可能继续增长;桩身应变幅值呈桩顶大、桩尖小的分布;桩土接触压力幅值分布规律与输入激励地震大小有关.
진행료가액화토-고층결구지진상호작용적진동태시험,시험채용유성용기이감소변계영향,채용포화사토작위모형토.시험중재현료액화장지토중고층결구적진해현상.득출적주요규률유:상호작용체계적진형곡선여강성지기상결구적진형곡선명현불동;수착진동차수적증가,체계적빈솔강저,조니비증대;사토대지진동가기려파화격진작용;당최초가속도봉치도체전,사토층중적공압비존재부치;진후토중공극수압력불일정수진동적정지이립즉개시소산,재단기내가능계속증장;장신응변폭치정장정대、장첨소적분포;장토접촉압력폭치분포규률여수입격려지진대소유관.
Shaking table model test was made on high-rise buildings with a consideration of the liquefiable soil-structure interaction with the saturated sand soil as model soil.A flexible container was fabricated to minimize the box effect.Macro-phenomena of high-rise building in ground of soil liquefaction due to natural earthquake were reproduced well.Test results show that the mode shape of the system is different from that of the structure on the fixed base in that there are rocking and swing at the foundation.The natural frequency of interaction system decreases and the damping ratio of soil increases with the increase of the shaking.The liquefied soil can filter and isolate vibration.Transient minus pore pressure occurs.Pore water pressure does not always dissipate in short time immediately after the excitations,but it may keep on increasing too.The distribution of the strain amplitude along the pile is the shape where the large strain is at the top of the pile and the small strain is at the tip of the pile.And the distribution of the contact pressure on the pile-soil interface is related to the excitation magnitude.