河北山前冲洪积平原区路基土的物理力学指标相关性研究

Research on Correlation of Physical and Mechanical Indexes of Subgrade Soil in Piedmont Alluvial and Proluvial Plain of Hebei Province

土的区域性影响高速公路工程的方案设计比选、沉降控制及造价分析,河北省分为多个地质分区,各个地质分区土的性质不同。以邯大高速公路S10标段采集到的1453份路基土土工试验数据为研究对象,对其变异性、概率分布特征和相关性进行了统计分析,得到了该地区路基土的物理力学指标变化范围,建立了指标相互之间的经验回归方程及相关系数。研究得出区域路基土的比重、湿密度、干密度的变异系数最小,压缩系数的变异系数最大;含水量、湿密度、塑性指数的概率分布模型均具有较高的相关系数,均大于0. 9,含水量、湿密度符合正态分布,塑性指数符合对数正态分布;压缩系数a1-2与孔隙比的相关性较大,在可靠度设计中应视为相互独立的变量。

The scheme design comparison and selection,settlement control and cost analysis of expressway engineering are influenced by the regionality of soil.Hebei province is divided into several geological zones,and the properties of soil in each geological zone are different.Taking the soil test data of 1453 subgrade soil collected from S10 bid section of Handan-Dalian expressway as the research object,the variability,probability distribution characteristics and correlation are statistically analyzed,the variation range of physical and mechanical indexes of subgrade soil in this area is obtained,and the empirical regression equation and correlation coefficient between the indexes are established.The results show that the coefficient of variation of specific gravity,wet density and dry density of regional subgrade soil is the smallest,and the coefficient of variation of compression coefficient is the largest;the probability distribution models of water content,wet density and plastic index all have high correlation coefficients,which are greater than 0.9;the water content and wet density conform to normal distribution,and the plastic index conforms to logarithmic normal distribution;the correlation between compression coefficient a1-2 and void ratio is relatively large,which should be regarded as independent variables in reliability design.