南京河西地区岩土体剪切波速与土层深度的关系

Relation between Depth and Shear Wave Speed of Bedrocks and Soils in Hexi District of Nanjing City

南京河西地区是南京市重点开发的新市区,该区域工程地质条件相似,主要为长江高河漫滩地质地貌单元。本文选取该地区47个典型钻孔的岩土体剪切波速资料,采用三种数学模型进行统计回归分析,运用相关系数R(或测定系数R2)检验Vs—H之间的线性相关关系,并根据计算的SD值选择较优的数学模型。统计结果表明,该地区各类岩土体的Vs—H线性相关关系显著,说明采用上述数学模型进行Vs—H回归是可行的。对两个工程场地进行剪切波速预测,并对场地类别作出划分,检验结果表明,该地区各类岩土体的Vs—H经验关系是可靠的,符合当地岩土特征,在样本深度范围内有足够的工程应用精度,可以应用。

Hexi district of Nanjing city is an important new developing area where the engineering geology is similar and its morphologic unit is a high flood plain of the Yangtze river. The data of shear wave speeds of bedrocks and soils at 47 typical boreholes in the district were selected for regressive statistic analyses with three mathematical models; the correlation coefficient R （or the measured coefficient R^2） was used to verify the linear correlation between Vs and H; the calculated SD values were based to select the best mathematical model. The regressive statistic analyses show that Vsand H of various bedrocks and soils in the district is remarkably correlated linearly, which indicates the regressive statistic analyses with the mathematical models are feasible. The forecast of the shear wave speeds and the classification of soils on two sites have shown that the empirical relation Vs-H of various bedrocks and soils in the district is reliable, accords with the feature of local bedrocks and soils, and is applicable for engineering in the range of sampling depths with sufficient accuracy.