水泥稳定碎石早期微裂干缩性能试验研究

Experimental Study on Dry-shrinkage Properties of Cement Stabilized Macadam after the Early Microcracking

为降低水泥稳定碎石的早期干缩应力,研究了微裂技术对水泥稳定碎石干缩性能的影响。首先对水泥稳定碎石进行早期微裂,然后利用干缩试验分析不同微裂时间、不同微裂程度对水泥稳定碎石材料干缩性能的影响。试验结果表明：水泥稳定碎石的干缩应变主要在养护初期形成,且在1~3 d内增长最快;微裂时间选在养生期第2d时,对早期干缩应变的降低最有利;微裂程度为40%时,早期干缩应变降低最多。

In order to reduce the early dry-shrinkage stress of cement stabilized macadam, the effect of microcracking to cement stabilized macadam dry-shrinkage properties was studied. Firstly, do the early microcracking to cement stabilized macadam, and then the effect of different microcracking tine and microcracking degree to cement stabilized macadam dry-shrinkage properties was analyzed through the dry-shrinkage test. The result shows that the dry-shrinkage strain of cement stabilized macadam is mainly formed in the early curing period and the fastest growth occurs in I-3 d; the suitable time to carry out microcracking is in the second day of the curing period in order to reduce the early dry-shrinkage strain; when the microcracking degree is 40%, the reduction of early dry-shrinkage strain is largest.