某场地砂土标贯试验N值与剪切指标相关性分析

Correlation Analysis Between N-Value and Shear Strength Indices of a Sandy Soil

基于对某场地典型砂土层工程性质认识的加深,提出了砂层的标贯击数值与剪切指标的拟合公式,并与规范公式、前人研究成果进行了对比分析,结果显示,以往在进行本地区砂层剪切指标赋值时相对偏保守,可以在原有经验值基础上适当提高。粘聚力经验公式表明本场地砂土粘聚力与标贯击数整体上呈负相关关系,内摩擦角经验公式相比Peck等三种模型,在结果准确性方面有了一定的提升。为此类场地砂土层剪切指标赋值提供了一种新思路,在一定程度上节约了工程成本,研究结果对类似工程有一定的参考价值。

Based on the increasingly understanding of the engineering properties of typical sandy soils,the empirical relationship between the Standard Penetration Test(SPT)N values and the shear strength indices is proposed.The proposed relationship was compared with the results of current design code recommended formula as well as the previous proposed relationship.The comparative results indicate that,compared with the proposed relationship,conservative design is usually obtained from both code recommended and previous recommended relationships when it is applied into the typical sandy soils.The design values could be slightly improved by applying the proposed empirical recommendations.The empirical formula for the cohesion shows that the cohesion of sandy soils and the SPT N values are reversely correlated.The empirical formula for the internal friction angle has a slight improvement in the accuracy of the results compared with the Peck and other three models.The proposed relationship provides a new approach for the evaluation of shear strength indies of the sandy soils in the studied site,and potentially saves the construction cost.