摘要
根据系统能量,由拉格朗日方程导出非线性地基-结构系统的动力方程,利用渐近解法(KBM)给出了系统共振区地震响应的渐近解,进而给出了共振区结构响应的振幅-频率响应数值结果,并分析了地基参数对结构振幅响应特性的影响。研究结果表明随着地基参数的变化,结构响应产生共振区畸变、振幅突变、“路径”效应与滞后现象等非线性性质,两突变点之间存在不稳定共振区;同一类型场地的地基,地基参数的变化对结构的动力特性有显著的影响,按现行抗震设计方法对非线性地基-结构系统进行抗震分析时,可能产生较大的偏差,需考虑这些非线性特性,使设计参数更合理和优化。
On the basis of system energy,the dynamic equations of nonlinear foundation-structure system are derived from Lagrange equation. The asymptotic solution and corresponding calculation results of amplitude- frequency are presented in seismic resonant area by means of asymptotic method (KBM),and then the influence of foundation parameters on properties of structure amplitude-frequency is analyzed. It is indicated that structure response emerges complex nonlinear properties along with the change of foundation parameters,such as distortion of resonant area,amplitude catastrophe,path effect and hysteresis,and there is the unstable resonant area between tow points of catastrophe. The value change of parameters of the same foundation type causes remarkable influence on structure dynamic properties. The calculation error by the current code of seismic design might be obvious for the analysis of nonlinear foundation-structure system. The nonlinear properties must be considered in order that design parameters are more reasonable and optimal.
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2004年第9期1509-1514,共6页
Chinese Journal of Rock Mechanics and Engineering
基金
广东省自然科学基金(010054)
广东工业大学科研基金(202015
982020)资助项目。
