水泥稳定再生骨料路面基层抗拉性能试验研究

Tensile Performance Test on Cement-stabilized Recycled Aggregate as Pavement Base

作为路面基层,水泥稳定骨料基层往往会受到白天和夜晚的温差影响,使材料内部产生胀缩应力,而作为路面的主要承重层,在受力不均匀情况下,基层混合料也会相当于受到一个外部剪切应力,因此,劈拉性能是其重要性能。通过水泥稳定碎石和水泥稳定再生骨料的劈拉强度及劈拉回弹试验,研究发现劈拉强度和回弹模量都随龄期呈幂指数增长。进一步对比分析发现水泥稳定再生骨料的劈拉性能要略逊于水泥稳定碎石,但通过适当提高水泥掺量可以弥补这一差距。最后,通过强度和模量之间的数值拟合可知其存在良好的线性关系。

As the base of pavement,cement-stabilized aggregate base mixture is affected by temperature difference between day and night which brings about swell-shrink stress inside the material.Meanwhile,cement-stabilized aggregate base mixture,as the major load-bearing layer of pavement,is subjected to an external shear stress under non-uniform stress.Splitting-tensile performance is a crucial indicator.In this paper,splitting tensile test and splitting tensile rebound test were conducted on cement stabilized clastic rock and cement stabilized recycled aggregate respectively.Test results suggest that the strength and modulus of elasticity both increased power-exponentially with age.The splitting-tensile performance of cement stabilized recycled aggregate is slightly lower than that of cement stabilized clastic rock;properly increasing the amount of cement could fill the gap.In addition,a good linear relationship is found between the strength and the modulus of elasticity via numerical fitting.