摘要
沥青混合料的动态模量是路面力学响应分析和结构设计的重要参数之一。为客观表征不同应力状态、试验温度及加载频率等试验条件对沥青混合料动态模量的影响规律,建立复杂服役条件下沥青混合料的动态模量预估模型,揭示沥青混合料动态模量的服役状态相关性。首先开展了不同温度、不同加载速率下沥青混合料的单轴压缩、间接拉伸及直接拉伸强度试验,揭示了不同温度下沥青混合料强度随加载速率的幂函数变化规律,为模量试验应力比的确定提供了依据。进而据此开展了不同温度与不同加载频率下沥青混合料的单轴压缩、间接拉伸及直接拉伸动态模量试验,提出了以等效应力比表征三维应力状态下模量试验应力比的沥青混合料动态模量分析方法,并基于时-温等效原理,采用Sigmoidal函数,建立了基于三维应力状态下等效应力比的动态模量归一化预估模型,实现了不同试验方法下沥青混合料动态模量的统一表征。研究结果表明:不同试验温度与应力状态下沥青混合料的强度均随加载速率的增大而增大,基于等效应力比表征的三维应力状态下模量试验应力比可实现不同试验条件下沥青混合料动态模量的统一表征,避免了路面结构设计时人为选取材料模量设计参数导致的设计结果不确定性。研究可为提高沥青路面结构设计的有效性和可靠性提供依据。
The dynamic modulus of asphalt mixtures is an important parameter for pavement mechanical response analysis and structural design.To objectively characterize the influence of different stress states,test temperature,and loading frequency on the dynamic modulus of the asphalt mixture,the prediction model under complex service conditions was established to reveal the service state correlation of the dynamic modulus.First,uniaxial compression,indirect tensile,and direct tensile strength tests reveal the power function variation law of strength with loading rate,which provides a basis for determining the stress ratio in the modulus test.Based on this,uniaxial compression,indirect tensile,and direct tensile modulus tests of asphalt mixtures under different temperatures and loading frequencies were carried out,and the dynamic modulus analysis method of asphalt mixtures with equivalent stress representing the stress ratio under a three-dimensional stress state was proposed.The sigmoidal function was adopted based on the time-temperature equivalence principle.A normalized prediction model of the dynamic modulus based on the stress ratio under a three-dimensional stress state was established,and a unified characterization of the dynamic modulus of the asphalt mixture under different test methods was realized.The results showed that the strength of the asphalt mixture under different stress states increased with an increase in the loading rate.The stress ratio under a three-dimensional stress state based on equivalent stress characterization can realize the unified characterization of the asphalt mixture dynamic modulus under different test conditions and avoid the uncertainty of design results caused by artificially selecting material modulus design parameters in the pavement structure design.This research can provide a basis for improving the effectiveness and reliability of asphalt pavement structural design.
作者
吕松涛
张乃天
吴政达
夏诚东
刘超超
葛冬冬
赵顺根
李喆
LYU Song-tao;ZHANG Nai-tian;WU Zheng-da;XIA Cheng-dong;LIU Chao-chao;GE Dong-dong;ZHAO Shun-gen;LI Zhe(School of Traffic and Transportation Engineering,Changsha University of Science&Technology,Changsha 410114,Hunan,China;International College of Engineering,Changsha University of Science&Technology,Changsha 410114,Hunan,China;Ganzhou Transportation Holding Group Corp.,Ganzhou 341300,Jiangxi,China;Transportation Quality Supervision Department of Inner Mongolia,Hohhot 010050,Inner Mongolia,China)
出处
《中国公路学报》
EI
CAS
CSCD
北大核心
2023年第4期27-37,共11页
China Journal of Highway and Transport
基金
国家杰出青年科学基金项目(52225806)
广西重点研发计划项目(AB20297030)
国家自然科学基金项目(52078063)
国家重大科研仪器研制项目(51927814)
内蒙古自治区交通科技项目(HMJSKJ-201801)
关键词
道路工程
沥青混合料
动态模量
强度
主曲线
应力比
road engineering
asphalt mixture
dynamic modulus
strength
master curve
stress ratio
作者简介
吕松涛(1979-),男,河南郑州人,教授,博士研究生导师,工学博士,E-mail:lst@csust.edu.cn;通讯作者:张乃天(1992-),男,河北承德人,工学博士研究生,E-mail:zntcs@stu.csust.edu.cn
