【摘要】 软土浅埋地铁车站结构的抗震能力分析是工程界关注的热点问题之一。为综合评价地震条件下,结构与场地材料性质、地基夹层非均匀性、地震动特性等对地下结构动力响应的影响,作者着重通过非线性时程响应模拟,并辅以时频联合分析技术,从多角度数值研究了软土浅埋地铁车站的地震响应特征与破坏机理。计算中,以DP弹塑性本构模型与接触面单元模型,模拟了土体材料非线性及土体-结构交界面的接触非线性的耦合作用。结果表明,相同地震载荷条件下,近场土体力学参数,及结构交界面处的接触非线性均会对地下结构的受力幅值及分布特征产生明显影响,需要在结构抗震设计中加以综合考虑,而不能单靠提高结构刚度来提高地下结构体的抗震能力。更多还原

【Abstract】 Seismic response analysis plays an important role in the damage mechanism of shallow underground structure in soft soil medium.By applying the coupling analysis method of DP elastic-plastic constitutive model and nonlinear contacting element model,many influencing factors are numerically investigated in the seismic analysis.In particular,effects on the structural response for the dynamical mechanic characteristics of structure,the soil layer properties and the seismic different time-frequency characteristics are investigated.The signal analysis technique is also employed to study the response characteristic of underground structure.It is demonstrated that such main nonlinear factors have great effects on the earthquake-resistant capacity of the underground structure,which should be comprehensively evaluated during the structural design phase of underground structure.更多还原