含水率与干密度对压实粉质壤土贯入阻力影响的试验研究

Experimental Study of the Influence of the Water Content and Dry Density on the Penetration Resistance of Compacted Silty Loam

通常,利用贯入阻力与干密度的统计关系可以将贯入法用于土体压实度的快速检测。然而,针对土体的力学强度特性,受含水率影响较大的土体单纯依靠贯入阻力难以准确评价其土体压实度。为研究含水率与干密度对压实后的中重粉质壤土贯入阻力的影响,配制了不同含水率和干密度的试样开展了静力贯入试验。试验结果表明:贯入阻力随含水率的增大呈线性减小,且两个线性拟合参数随干密度的增大呈幂函数增长。在此基础上,给出了考虑含水率和干密度共同影响的压实粉质壤土贯入阻力计算模型。之后,将模型计算值与所得到的试验结果以及相关文献中压实黄土的贯入试验结果进行了对比,验证了该模型能够较好地预测中重粉质壤土的贯入阻力,且对其它类型的土体也具有较好的适用性。

Usually,by using the statistical relationship between penetration resistance and dry density,the static penetration method has been used for the rapid detection of soil compactness.However,for soils whose mechanical properties are greatly affected by water content,it is difficult to evaluate soil compaction accurately by using penetration resistance only.To study the effect of water content and dry density on the penetration resistance of compacted medium-heavy silty loam,samples with different water content and dry density were prepared,and static penetration test was conducted.The results show that the penetration resistance decreases linearly with the increase of water content,and the two fitting parameters increase as a power function with increasing dry density.On this basis,the calculation model of penetration resistance is proposed,which could consider the both influence of water content and dry density.Finally,the model predictions were compared with the penetration test results in this paper and from other relevant literature.The result shows that the proposed calculation model can predict the penetration resistance of medium-heavy silty loam well.In addition,this model can be used for other types of soil as well.