多场耦合作用下多孔沥青混凝土的高温性能

High-temperature Performance of Porous Asphalt Concrete Under Multi-physics Coupling

基于降雨过程,设计了符合实际降雨过程的四种耦合试验条件,分析了温度、多场耦合条件、荷载水平对多场耦合作用下的高温性能的影响,研究开发的多物理场动态蠕变试验对多孔沥青混凝土在多场耦合作用下的高温性能进行评价。试验结果表明不同降雨条件下的多孔沥青混凝土按照高温性能由强到弱,依次为降雨结束、干燥、降雨开始和降雨中;高温浸水时间影响混凝土的高温性能,降雨过后尽快排出路面结构内的雨水,能够改善排水路面的高温抗车辙能力;多孔沥青混凝土在干燥和降雨开始条件下为压裂破坏,降雨中条件下为剪裂破坏,降雨结束条件下同时有剪裂和压裂破坏;高温和超载现象会显著降低多孔沥青混凝土在多场耦合作用下的使用寿命,加速水损害对多孔沥青混凝土高温性能的影响,加大混凝土在浸水和非浸水状态之间的性能差异。

Based on the rainfall process,four coupling test conditions conforming to the actual rainfall process were designed,and the effects of mix type,temperature,multi-field coupling conditions,and load level on the high-temperature performance under multi-field coupling were analyzed.The multi-physics dynamic creep test was developed to evaluate the high temperature performance of porous asphalt concrete under multi-field coupling effect.The result indicates that the four precipitation conditions were sorted in the following orders according to the high-temperature properties of porous asphalt concrete(from the highest quality to the lowest quality):rainfall end condition,dry condition,rainfall onset condition,ongoing rainfall condition.The high-temperature soaking time affects the high-temperature performance of concrete.The drainage of rainwater within pavement structure as soon as possible after rainfall can improve the high-temperature rutting resistance of drainage pavement.The crushing fracture occurs under dry and rainfall onset conditions.The shear fracture is found in ongoing rainfall condition,and the mixed crushing/shear fracture is found in rainfall end condition.The high temperature and overload phenomena can significantly reduce the service life of porous asphalt concrete under multi-physics coupling,that accelerates the effect of water damage on the high temperature performance of porous asphalt concrete,and increases the difference in performance between submerged and non-submerged states of concrete.