公路路面结构及路表排水设计分析

Analysis of Highway Pavement Structure and Surface Drainage Design

为了提高公路工程的设计质量,减小路面开裂、车辙、坑槽等问题,首先以广东省道S355线为研究对象,基于交通量OD调查计算了设计车道的当量设计轴载累计作用次数,判断出车道等级为重交通;其次,利用路面设计软件设计了基层厚度,对沥青层疲劳寿命、无机结合料层疲劳寿命、沥青层永久变形量、路基顶面竖向压应变、低温开裂系数等指标进行验算,并利用结构设计软件建立计算模型,计算了沥青路面的层底拉应力和沥青层永久变形量,与公路路面设计软件的计算结果进行对比,两者误差在3.0%内。最后,从路面表面排水设计和坡面排水计算两方面分析了路表排水设计,并结合工程案例阐述了坡面容许流速、边沟流速的验算方法,验算结果均满足规范的要求,说明排水方案是可行的。

In order to improve the design quality of highway engineering and reduce pavement cracking,rutting,potholes and other problems,Firstly,taking Guangdong Provincial Highway S355 as the research object,and the cumulative number of equivalent design axle load actions of the design lane is calculated based on the traffic volume OD survey,and the lane level is determined as heavy traffic;Secondly,the thickness of the base layer was designed using road design software,and fatigue life of asphalt layer,fatigue life of inorganic binder layer,the permanent deformation of the asphalt layer,the vertical compressive strain of the roadbed top surface,and the low-temperature cracking coefficient were verified.A calculation model was established to calculate the tensile stress at the bottom of the asphalt pavement layer and the permanent deformation of the asphalt layer.The results were compared with those of HPDS software,and the error between the two was within 3.0%.Finally,the road surface drainage design and slope drainage calculation were analyzed from two aspects,and the calculation methods for allowable flow velocity on the slope and side ditch flow velocity were explained based on engineering cases.The calculation results met the requirements of the code,indicating that the drainage scheme is feasible.