排水沥青路面空隙堵塞试验研究

Study on pore blocking performance of porous asphalt pavement by laboratory test

粉尘颗粒堵塞是导致排水沥青路面排水功能衰减的重要原因,为了研究排水沥青路面空隙颗粒堵塞特性,通过模拟堵塞试验研究了排水沥青混合料堵塞颗粒敏感粒径;通过渗透性能衰变试验,结合Wojtanowicz堵塞机理模型,研究不同粒径颗粒在不同空隙率的排水沥青混合料中的堵塞规律。研究表明:粒径0.6~2.36 mm的颗粒最容易阻塞在排水沥青混合料内部。含颗粒流体对于排水沥青混合料的堵塞分为三个阶段。第一阶段渗透系数残留率与堵塞颗粒质量线性相关,颗粒在混合料内部孔喉处的堵塞占主导地位;第二阶段空隙结构表面颗粒吸附与沉降以及颗粒的大量堆积所占的比例逐渐提高;第三阶段含颗粒流体从较大连通空隙流出混合料,排水沥青混合料渗透系数逐渐稳定。

Blocking is an important reason for loss of permeability of porous asphalt pavement.In order to study the blocking performance of porous asphalt pavement,the sensitive particle size of blocking particles is achieved by simulated blockage test.Based on Wojtanowicz pore blocking mechanism,the blocking law of porous asphalt mixture with different porosity is achieved by permeability decay test.The results show that,the porous asphalt mixture is easy to be blocking by the particles with diameter of 0.6~2.36 mm.The blocking process of porous asphalt mixture can be divided into three stages.In the initial stage,the remaining rate of permeability coefficient has a good linear relationship with the total mass of particles.The pore throat blocking is the domination mechanism.In the second stage,the pore surface deposition and pore filling become the dominant mechanism.In the third stage,fluid with particles flows out of mixture from larger connected voids,the permeability coefficient of porous asphalt mixture stabilizes gradually.