老化对水泥沥青复合胶结料粘弹特性的影响

摘要

为了研究老化对水泥沥青复合胶结料蠕变特性及粘弹性力学参数的影响,结合不同材料配比的水泥沥青复合胶结料的老化试验及蠕变试验,分析了老化时间及材料配比对复合胶结料粘弹性力学参数的影响.建立了考虑老化影响的粘弹性力学参数的演化方程;基于三元件四参数分数导数模型,提出了水泥沥青复合胶结料的老化因子,建立了水泥沥青复合胶结料的老化预测模型.研究表明:随着材料老化程度的加深,水泥沥青复合胶结料的弹性成分所占比例增加,粘性成分减少;水泥沥青复合胶结料的老化速度在老化前期变化较快,随老化时间增加老化速度减缓;适当提高沥青的用量可以在发生老化的情况下使材料仍具有较好的柔性及变形能力.所建立的老化因子能够同时反映老化时间、配合比等因素对水泥沥青复合胶结料粘弹特性的影响.%This study aimed to investigate the effects of aging on the creep property and viscoelastic mechanical pa-rameters of cement-asphalt composite binder. By combining the aging test and creep test of cement-asphalt compos-ite binder with different material ratios,the effects of aging time and material ratio on the mechanical parameters of cement-asphalt composite binder were analyzed. An evolution equation on the viscoelastic mechanical parameters considering the influence of aging was established. On the basis of the fractional derivative model of three elements and four parameters, an aging factor of cement-asphalt composite binder was proposed, and an aging prediction model was established. Results show that the elastic components of cement-asphalt composite binder increased and the viscous components decreased when the aging extent deepened. The aging speed of cement-asphalt composite binder changed quickly in the initial stage of aging but slowed as the aging time elapsed. By properly increasing the consumption of asphalt,the material could maintain improved flexibility and deformability in the case of aging. The established aging factor could simultaneously reflect the effects of aging time and mix ratio on the viscoelastic prop-erties of cement-asphalt composite binder.