三维黏弹性介质人工边界研究

为了得到适于分析非线性结构-地基相互作用问题的人工边界，结合弹性波理论与黏弹性理论，推导出了适于模拟三维黏弹性远场介质辐射阻尼的人工边界，并对其模拟远场地基辐射阻尼的性能及相应地震波动输入方法进行了研究。结果表明：在结构-地基动力相互作用问题中，得到的黏弹性人工边界模拟计算域外远场黏弹性介质的辐射阻尼具有理想精度；不论是简谐波还是非简谐波，地震波动输入都取得了理想结果；在黏弹性介质条件下自由地表处的总场位移幅值n是输入波幅值的 倍。

Study of three dimensional viscoelastic medium artificial boundary

In order to get the artificial boundary that suits to analyze nonlinear structure-foundation interaction problems, the viscoelastic artificial boundary simulating radiation damping of the far field medium was obtained from the elastic wave theory and viscoelasticity theory. The ability of viscoelastic artificial boundary to simulate radiation damping and methods of seismic wave motion input were studied. The results show good precision when simulating radiation damping of far fields with the viscoelastic artificial boundary obtained from this paper in solving structure-foundation interaction problems. Precise results can be obtained through seismic wave motion input methods obtained in this paper whether the input wave is simple harmonic one or simple nonharmonic one. The displacement peak value at the free earth surface is times as high as that of input wave in viscoelastic medium.