长江下游地区新近沉积土动剪切模量比和阻尼比的试验研究

通过对长江下游地区南京、苏州、常州、徐州、泰州、盐城、扬州、无锡、镇江、张家港、连云港、启东、常熟、江阴、宿迁等15个城市的淤泥质粉质粘土、粘土、粉质粘土、粉质粘土与粉砂互层土、粉土、粉细砂和粗砂等七类新近沉积土共计275个原装土样历时3年的自振柱试验研究,给出了长江下游地区七类新近沉积土的动剪切模量比 G/Gmax和阻尼比λ与剪应变幅值γ变化的平均曲线的拟合曲线、包络线及其参数的推荐值。由于未见报道其他研究者对长江下游地区新近沉积土动力参数的系统研究,该研究成果有利于加深对该长江下游地区各类新近沉积土动力特性的认识,并对该地区各类工程建设的工程场地地震安全性评价工作具有一定的借鉴和参考价值,且有利于推动长江下游地区工程场地地震安全性评价工作的开展。

Experimental Study on Dynamic Shear Modulus Ratio and Damping Ratio of Recently Deposited Soils in the Lower Reaches of the Yangtze River

Dynamic experimental study on a total of 275 soil samples has been conducted with free vibration column apparatus.These samples are recently deposited soils, which include mucky silty clay, clay, silty clay, silty clay and silty sand interbedded strata, silt, fine sand and coarse sand, taken from cities of Nanjing, Suzhou, Changzhou, Xuzhou, Taizhou, Yancheng,Yangzhou, Wuxi, Zhenjiang, Zhangjiagang, Lianyungang, Qidong, Changshu, Jiangyin and Suqian in the area of the lower reaches of the Yangtze River. The envelopes, fitting curves and recommended values of dynamic shear modulus ratio G/Gor / and damping ratio λ versus shear strain amplitude γ for 7 types of soils are also presented. Since there is no similar study in this respect, this studymay be of significance to understand dynamic characteristics of recently deposited soils in this area.Moreover, the experimental results can provide a reference for seismic safety evaluation of engineering sites in this area.