土壤固化剂稳定粉质黏土性能的试验研究

Experimental Study on Performances of Silty Clay Stabilized by Solidification Agent

以河南省境内某段高速公路附近的粉质黏土为原材料,通过室内试验,首先对比了掺或不掺固化剂的情况下,水泥质量分数分别为5%,10%,15%和20%时集合料的7 d无侧限抗压强度,结果表明掺固化剂能明显提高集合料的无侧限抗压强度;其次制备了不同配合比的集合料试件,分析了水泥和固化剂含量对集合料最大干密度、最佳含水量、7 d和28 d无侧抗压强度2、8 d间接抗拉强度的影响,综合试验结果与成本等因素,选定了最优配合比为m(水泥)∶m(固化剂)∶m(粉质黏土)=4∶8∶88;最后,对该最优配合比进行了延迟和干缩等路用性能试验及SEM微观分析,并在某高速公路选取100 m的底基层进行了现场试验和追踪调查,结果表明上述最优配合比集合料完整密实且强度较高,未出现病害,路用性能较好.

Some kind of silty clay near one highway in Henan Province was taken as subgrade material,and 7 d unconfined compressive strength was firstly tested, which increased markedly when it was mixed with solidification agent.Secondly some samples were prepared with different mix proportions（mass proportion of cement,solidification agent and silty clay）.The influences of cement and solidification agent on the maximum dry density,optimum moisture content,7 d and 28 d unconfined compressive strength,and 28 d indirect tensile strength were investigated,and the mix proportion of 4∶8∶88 was selected as the best proportion based on the test results and economical factors.Finally,as to this best mix proportion,delay time and dry shrinkage properties were tested indoors, microscopic analysis was made from the SME picture,some in-situ investigations were made at the selected 100 m segment in the above-mentioned highway subgrade.All results reveal that the mixtures have better integrity,strength and pavement performances.