沥青混合料饱水过程的强度演化规律及机理分析  

Strength Evolution Law and Mechanism Analysis of Asphalt Mixtures during Water Saturation

作　　者：任敏达 冯汉卿 丛林[1] 刘人玮 REN Minda;FENG Hanqing;CONG Lin;LIU Renwei(Key Laboratory of Road and Traffic Engineering of the Ministry of Education,Tongji University,Shanghai 201804,China;Civil Aviation Design and Research Institute,China Design Group,Beijing 101312,China)

机构地区：[1]同济大学道路与交通工程教育部重点实验室,上海201804 [2]华设设计集团北京民航设计研究院有限公司,北京101312

出　　处：《建筑材料学报》2022年第5期537-544,共8页Journal of Building Materials

基　　金：国家自然科学基金资助项目(51878499);山东省交通运输厅科技计划项目(2021B47);民航机场安全与运行工程技术研究中心开放课题(KFKT2021-07);中央高校基本科研业务费专项资金资助项目(22120200447)。

摘　　要：为研究SBS改性沥青混合料在饱水过程中的力学强度演化过程,提出了一种基于圆孔孔边应力集中效应的力学模型,分别计算了非饱水和饱水孔隙的孔边应力.对不同沥青含量的SBS改性沥青混合料试件进行水敏感性试验(MIST)和恒温浸水试验,采用间接拉伸强度(ITS)和拉伸强度比(TSR)来表征沥青混合料的强度演化过程,分析孔隙水压循环次数、水浴时间、孔隙水压力和温度对沥青混合料强度的影响.结果表明:在劈裂荷载作用下,孔隙水压抗力消散了薄弱孔隙的应力集中;随着孔隙水压循环次数或恒温水浴时间的增加,试件的ITS先减小后增大,TSR持续增大;沥青混合料在饱水过程中的强度增加,实际上采集到的是沥青混合料自身强度与孔隙水压力的加和;温度对沥青混合料强度的影响比孔隙水压力的影响更加显著.In order to study early strength evolution of saturated SBS modified asphalt mixture,a mechanical model based on effect of stress concentration at circular hole was proposed,and the pore-edge stress of non-saturated and saturated pore was calculated respectively.Moisture induced susceptibility test and immersion test were carried out for asphalt mixture with different asphalt contents.Then indirect tension test was utilized to obtain the indirect tensile strength and tensile strength ratio.The results show that under the splitting load,the pore water pressure dissipates the stress concentration phenomenon of the weak pore.With the increase of the moisture induced susceptibility test cycle times and the bath time,the indirect tensile strength first decreases and then increases,and the tensile strength ratio continues to increase.The strength of the asphalt mixture in the process of moisture conditioning increases,because the sum of asphalt mixture strength and pore water pressure is collected together in fact.The influence of temperature on the strength of asphalt mixture is more significant than that of pore water pressure.

关 键 词：沥青混合料 饱水过程 水敏感性试验 孔隙水压循环 间接拉伸试验 强度演化 

分 类 号：U414[交通运输工程—道路与铁道工程]