南京新近沉积土动剪切模量比与阻尼比的试验研究

通过对南京淤泥质粉质粘土、粉质粘土、粉质粘土与粉砂互层土、粉土、粉砂和细砂等6类新近沉积土120个原状土样、历时4 a的试验研究,给出了南京6类新近沉积土的动剪切模量比G/Gmax和阻尼比D随剪应变幅值γ变化的平均曲线的拟合曲线及其参数的推荐值。为便于一般工程借鉴,给出了该6类新近沉积土的G/Gmax–γ和D–γ试验曲线的典型值。该成果有利于加深对南京新近沉积土动力特性的认识,并对该地区一般工程建设场地的地震安全性评价工作具有借鉴和参考价值。

Experimental studies on dynamic shear modulus ratio and damping ratio of recently deposited soils in Nanjing

The results of free vibration column tests on 120 undisturbed samples of recently deposited soils in Nanjing including mucky silty,soil clay,silty clay,silty clay and silty sand interbedded strata,silt,fine sand were analyzed.The fitting curves of average relation of dynamic shear modulus ratio G/Gmax and damping ratio D with shear strain amplitudeγ as well as their parameters in the empirical formula of G/Gmax–γ and D–γ curves for 6 types of soils above mentioned were presented.Moreover,their typical values were provided for practical application.These findings would provide more knowledge about dynamic characteristics of recently deposited soils in this area,and could be used as reference for seismic safety evaluation of general engineering sites.