摘要
天津滨海地区是典型的软土区,属晚第四系以来的浅海相沉积软土。本文收集了该地区地震安全性评价报告中的土动力学参数的实验资料,并补充了15个钻孔的测试实验,统计分析了淤泥质粘土、淤泥质粉质粘土、粉土、粉质粘土、粘土、粉砂、细砂等7种土类的实测土动力学参数,给出了它们在不同深度下的动剪切模量比和阻尼比的统计值。然后,选取了2个典型钻孔并建立了土层地震反应分析模型,分别运用本文统计值、94规范值和袁晓铭等(2000)的推荐值进行土层地震反应计算,从反应谱形状、地表峰值加速度和反应谱特征周期等方面说明了本文统计值的适用性和针对性。本文的研究成果对天津滨海地区各类工程建设的场地地震安全性评价工作具有一定的借鉴和参考价值,且有利于该地区工程场地地震安全性评价工作的开展。
Tianjin coastal area is a typical soft soil site region,where the soil is marine deposit since late Quaternary.In this paper,soil dynamic parameters from seismic risk assessment reports are collected,and dynamic characteristics of samples from 15 drilling holes are measured and analyzed.The data in this study are divided into 7 types based on lithology,i.e.muddy clay,muddy silty clay,silt,silty clay,clay,silty sand and fine sand.Statistics of the dynamic parameters of these soils are carried out to obtain the mean values of dynamic shear modulus ratio and damping ratio at different depth.Then two typical drilling are selected to establish soil dynamic models in order to investigate the seismic response in different cases.The dynamic parameters in the models are taken from statistical values in this study,recommended values in 94 Code and recommended values by Yuan Xiaoming respectively.The applicability and pertinence of the statistical value obtained in this paper are demonstrated by the response spectrum shape,peak ground acceleration and response spectral characteristics.Our results can be taken as a reference of the soil dynamic value in this area and can be used in seismic risk assessment of engineering projects.
出处
《震灾防御技术》
2010年第3期288-298,共11页
Technology for Earthquake Disaster Prevention
基金
中国地震局地壳应力研究所中央级公益性科研院所基本科研业务专项ZDJ2009-07和ZDJ2009-23资助
关键词
场地土
土动力学参数
软土
天津滨海
Site soil
Soil dynamic parameter
Soft soil
Tianjin coastal area
