竖向地震作用下地下结构非线性振动过渡阶段研究  

Study on Transition Stage of Nonlinear Vibration of Underground Structure under Vertical Seismic Action

作　　者：沈偲然 戚承志 郭云鹏 刘英奇 Shen Siran Qi Chengzhi Guo Yunpeng Liu Yingqi(School of Civil and Traffic Engineering, Beijing Future Urban Design High-Tech Innoration Center Beijing University of Civil Engineering and Architecture, Beijing 100044)

机构地区：[1]北京建筑大学土木与交通工程学院北京未来城市设计高精尖创新中心,北京100044

出　　处：《北京建筑大学学报》2017年第3期7-14,共8页Journal of Beijing University of Civil Engineering and Architecture

基　　金：国家自然科学基金项目(51478027;51174012);973国家重点基础研究发展计划(2015CB0578005)

摘　　要：采用了非线性土力学模型,研究了结构在竖向地震作用下的动力响应规律.取用p=K1w-K3w3地基反应力模型,推导得到了结构的非线性运动方程.假设阻尼比为小量,用平均法求解运动方程的近似解析解.通过数值计算详细分析了结构的运动规律,特别是过渡阶段的运动规律.研究发现,考虑非线性效应后,位移和振动周期变大,运动的不规律性增强.同时发现随着地震强度的增加,振动的非线性行为更加显著.In this paper, a nonlinear soil dynamic model is used to study the dynamic response of rigid frame under vertical seismic action. The relationship between reaction force of soil and relative displacement of rigid structure is p = K1w - K3w3 , and the equilibrium equation of the structural rigid body is obtained by the dynamic D＇Alembert＇s principle. The approximate analytical solution of the generalized Duffing equation is obtained by means of the averaging method, and the motion regulation is analyzed in detail. It is found that the nonlinearity of the model increases the periodicity of vibration and the irregularity of motion. Also the seismic acceleration has a significant influence on the eharacterisrics of vibration.

关 键 词：地下结构 地震作用 近似解析解 非线性振动 

分 类 号：TU93[建筑科学—结构工程] TU435