土的天然密度对地表地震动参数的影响

摘要

We select three artificial ground motion time histories in different intensities as in bedrock ground motion inputs.By using the equivalent linearization wave method on the one-dimensional soil frequency domain,we analyze the seismic response of soil layers.The paper studies 2 kinds of soil profile.Their natural density impacts the ground motion parameters.We also analyze characters of peak acceleration and response spectrum.These studies show a negative correlation between surface peak acceleration and soil's natural density,and that the soil's natural density increases as the peak acceleration decreases.The correlation between characteristic periods of surface acceleration response spectrum and soil density is ambiguous.%选择3种不同强度的人造地震动加速度时程作为基岩地震动输入,采用一维土层频域等效线性化波动方法进行土层地震反应分析,研究两种不同土性的土层剖面,在一定范围内土的天然密度变化对场地地袁地震动参数的影响,分析了峰值加速度和反应谱特征周期的变化趋势.结果表明,地表峰值加速度与土层的天然密度存在负相关关系,土体的天然密度增大,地震动峰值加速度逐渐减小.地表加速度反应谱特征周期与土体密度的变化相关关系不明显.