级配碎石排水性能及基层排水系统研究

Study of Drainage Performance of Graded Crushed Stone and Base Drainage System

在半刚性底基层和面层之间设置级配碎石基层,可有效解决半刚性基层沥青路面结构排水性能差的缺陷。采用自行研制的渗透仪测试了6种不同空隙率级配碎石的渗透系数,计算了自由水在级配碎石基层的渗流时间和渗流路径,用路面渗水仪比较分析了级配碎石和水泥稳碎石的透水效果,设计了两种路面内部基层排水系统。结果表明,渗透系数与空隙率有很好的相关性,随着空隙率增加,级配碎石的渗透系数增加;渗入水在路面结构内的渗流时间缩短,排水性能提高;级配碎石基层具有良好的排水效果,可减少水损害的发生。通过设计的基层排水系统,可将级配碎石基层中的水排出路面结构以外。

Setting up graded crushed stone base between semi-rigid subbase and surface can effectively solve the disadvantage of poor drainage performance of semi-rigid type base asphalt pavement.The permeability coefficients of six kinds of graded crushed stone with different porosities were measured by using the permeameter designed by the authors,and the seepage time and path of free water in the graded crushed stone base were calculated.The different drainage performance of graded crushed stone and cement stabilized gravel were compared and analysed with seepage meter.Two kinds of base drainage system for pavement were designed.The result illustrates that（1）permeability coefficient and porosity have good correlation,the permeability coefficient of graded crushed stone increases with the increases of porosity;（2） the seepage time is shortened and the drainage performance of pavement structure is improved;（3） the graded crushed stone base has good drainage effect which can decrease the occurrence of water damage,the water in the graded crushed stone base can be drained via designed base drainage system.