【摘要】 采用数值模拟方法,研究动剪切模量比和剪切波速对地震动的影响问题,并以对地表加速度反应谱影响为标准研究动剪切模量比变化与剪切波速变化间的对等关系,同时建立了等价关系式,分析中考虑了场地类别、场地遭遇地震强度和地震输入波型的影响。结果表明:①动剪切模量比误差和剪切波速误差对地震动都有着重要影响,在土体强非线性和软弱场地中影响更为强烈,实测的动剪切模量比和剪切波速比真实值低时较比真实值高时对地表反应谱影响更大,三类场地0.1g地震输入时动剪切模量比6%误差或剪切波速25%误差的影响已经不可忽视;②对不同的场地类别、场地地震烈度和地震输入波情况,动剪切模量比单独变化与剪切波速单独变化对反应谱的影响都具有对等关系;③动剪切模量比误差对地震动的影响程度要大于剪切波速误差,二者对地表反应谱的敏感性相差3～5倍,绝对误差相同时动剪切模量比降低情况下与剪切波速的敏感程度相差更大。更多还原

【Abstract】 The effects of the dynamic shear modulus ratio and the shear wave velocity on the surface ground motion and their equivalent effect relations with surface acceleration spectra are investigated by use of the numerical simulation method considering site types, incident seismic intensities and incident seismic wave forms. The results indicate that the errors of dynamic shear modulus ratio and the shear wave velocity both have strong effects on the surface ground motion. The effects of the dynamic shear modulus ratio and the shear wave velocity are more significant for strong nonlinear property in the weak site as well as for the cases when the two parameters by the tests are lower than the actual values, e.g., 6% error of the dynamic shear modulus ratio and 25% error of the shear wave velocity for 0.1g incidence in site Ⅲ can not be neglected. The effects of the dynamic shear modulus ratio alone and the shear wave velocity alone on the spectra can be expressed by the equivalent relationships for different site types, incident seismic intensities and incident seismic wave forms. The extent of the effects of the dynamic shear modulus ratio on the spectra is much larger than the shear wave velocity by 3~5 times and the difference of the sensitive extent between the two parameters for the decreasing of the dynamic shear modulus ratio is more obvious than that of the cases for the increasing of the dynamic shear modulus ratio.更多还原