粗集料对水泥稳定石屑击实和强度特性的影响研究

为提高水泥稳定石屑的强度且便于工程操作,提出在水泥稳定石屑混合料掺入单一粒径的粗集料。试验研究粗集料掺量对混合料击实特性和强度特性的影响。分别将粒径规格为4.75mm^9.5mm和9.5mm^19mm的粗集料掺入到水泥稳定石屑中,设定不同粗集料和石屑比例,测试混合料的击实曲线、7d无侧限抗压强度和间接抗拉强度,并与不掺入粗集料的水泥稳定石屑相比较。试验结果发现:当粗集料掺量不超过50%时,两类掺入粗集料的水泥稳定石屑级配仍属于悬浮密实型,混合料压实曲线突起部分随粗集料掺量增加逐渐变窄,表明混合料对含水率逐渐敏感。掺入粗集料后混合料强度和抗缩裂性能均有所提高,粗集料粒径规格越大,掺入量越大,性能提高越明显。

Study on Effect of Coarse Aggregate on Compaction and Strength Characteristics of Cement Stabilized Stone-chip

To increase the strength of cement stabilized stone-chip CSS and be convenient for construction,the CSS mixing with single particle of coarse aggregates was proposed.The effect of mixing amount of coarse aggregates on mixture was experimentally studied.The coarse aggregates of grain sizes of 4.75mm^9.5mm and 9.5mm^19mm are respectively incorporated into CSS.The proportion of coarse aggregates and stone-chip is varied.The compaction curve,7d unconfined compressive strength and indirect tensile strength are tested.The comparisons between CSS with and without coarse aggregates are conducted.The result shows that the grain composition of these two types of CSS maintains suspendeddense structure when the proportion of coarse aggregates is less than 50%.The bulges on compaction curve of mixture become narrow with the increasing of the proportion of coarse aggregates,which indicates that the sensitivity of water ratio to mixture increase.The strength and antishrink of mixture are improved obvious due to the coarse aggregates.The larger grain size and proportion of coarse aggregate is able to get the better performance.