宁夏南部山区粉土孔隙比与标准贯入击数关系研究

Relationship between Porosity Ratio and Standard Penetration Number of Silty Soil in Southern Mountain Area of Ningxia

粉土的密实度与孔隙比存在对应关系,但粉土的密实度与标准贯入击数缺乏对应关系。根据宁夏南部山区某住宅小区钻孔内黄土状粉土标准贯入击数(N)、原状样室内试验孔隙比(e)随钻孔深度(H)变化的数据,利用粒子群算法作回归分析,拟合了其与深度的回归方程,从而得出标准贯入击数(N)、孔隙比(e)均与深度呈线性关系,且表现出很好的相关性。随之拟合了孔隙比(e)与标准贯入击数(N)的回归方程,从而得出孔隙比(e)与标准贯入击数(N)呈线性关系,且表现出很好的相关性。进而得出,利用现场原位标准贯入试验划分宁夏南部山区同心县城区黄土状粉土密实度具有较高可靠性,研究成果为建立地区标准贯入击数(N)判别黄土状粉土密实度经验提供了基础性资料。

There is a corresponding relationship between the compactness of silt and the void ratio,but there is no corresponding relationship between the compactness of silt and the number of standard penetration.In this paper,the statistical data of SPT(N)and void ratio(e)of undisturbed samples in a residential area in the southern mountainous area of Ningxia with the variation of drilling depth(H)are presented.The linear regression analysis based on mathematical statistics is used and the regression equation is fitted.The results show that there is a line relationship of both the SPT blow number(N)and the void ratio(e)with the depth showing a good correlation.These results show that the in-situ SPT test has high reliability in dividing the density of loess silty soil in the urban area of Tongxin County in the southern mountainous area of Ningxia.This study provides basic data for the experience of loess silty soil compaction and establish regional standards.