摘要
在土－结构动力相互作用分析中，下覆地基对基础与结构的阻抗函数通常强烈地依赖于外加激振频率．当结构为线性时，耦联体系的动力分析可采用子结构法在频域上有效地实施．但对于非线性结构，在时域上采用与频率有关的动力阻抗进行相互作用分析就变得十分困难与复杂．而单靠采用某一频率下动力阻抗函数固定值的单自由度集总参数模型不能充分地包含所有频率成分而难以反映实际性态．为了克服这些困难与缺陷，根据地基阻抗函数的解析和数值解答，发展了可用于时域分析的双自由度集总参数模型，其中所含有的８个与频率无关的定常参数可通过曲线优化拟合求取．这种离散模型简便实用，且与工程惯例相协调。
In the dynamic soil structure interaction analysis, the dynamic impedances of foundation soils on the super structure and footing are of frequency dependent nature. Frequency domain formulations for solving seismic response of coupling systems have gained popular usages for linear elastic problems. For nonlinear systems in common practice, it is difficult to perform soil structure interaction analysis in time domain while the frequency dependent impedances are directly employed. The conventional simple lumped parameter model with constant spring and damping coefficients cannot simulate the actual behaviour of foundation and soil system. In order to overcome these deficiencies and drawbacks, a two degrees of freedom mechanical model with 8 constant lumped parameters is developed for the foundation dynamic impedances on the basis of accurate values of soil impedances evaluated by numerically solving actual boundary value problems. This discrete model is simple and applicable in practice. It provides a useful basis for the nonlinear analysis of soil structure interaction system in the time domain.
出处
《大连理工大学学报》
CAS
CSCD
北大核心
1996年第4期477-482,共6页
Journal of Dalian University of Technology
基金
国家自然科学基金及国家教委留学回国人员科研基金
关键词
振动
动力阻抗
地基
集总参数模型
自由度
foundation vibration
time domain analysis/soil structure interaction
dynamic impedance
lumped parameter model
