寒区城市BRT车道路面病害调查与路面结构设计

Investigation of BRT lane pavement diseases and pavement structure design in cold region cities

根据兰州当地条件,分析总结了现有的兰州BRT专用车道产生车辙、拥包、推挤、裂缝等路面病害的原因。并基于GeoStudio软件分析BRT车道路面的应力应变情况和太阳辐射在路面材料结构中的传导状态,发现了车辙、拥包等道路路面病害的作用形式和产生病害的直接原因。通过对现状、抗车辙沥青、改变集料粒径配比,三种路面状况进行时间上的纵向对比和几种状况关于沉陷、应力的横向对比,发现抗车辙沥青的保温隔热效果优于玛蹄脂沥青面层材料,而玛蹄脂沥青材料在抗弯沉模量和耐磨性上表现更好。通过对方案的对比分析得出结论,使用玛蹄脂沥青材料做面层,在面层和基层中间加铺土工材料和预应力层并对基层实施预切缝为适合的改进方案。

According to the local conditions in Lanzhou,the causes of rutting,crowding,pushing,cracking and other pavement diseases of the existing Lanzhou BRT dedicated lanes are analyzed and summarized.And based on GeoStudio software to analyze the stress-strain situation of BRT lane pavement and the conduction state of solar radiation in the pavement material structure,the form of rutting,congestion and other road pavement diseases and the direct cause of the disease were found.Through the status quo,rutting-resistant asphalt,changing the aggregate grain size ratio,three pavement conditions for the longitudinal comparison in time and several conditions about the subsidence and stress of the horizontal comparison,found that the rutting-resistant asphalt heat insulation effect is better than the horseshoe asphalt surface material,and horseshoe asphalt materials in the flexural modulus of sedimentation and abrasion resistance to perform better.Through the comparative analysis of the program,it is concluded that the use of horseshoe asphalt material for the surface layer,in the middle of the surface layer and the grass-roots level with geotechnical materials and pre-stressing layer and the implementation of the grass-roots level of pre-cut joints as a suitable program for the improvement of the program.Based on the local conditions in Lanzhou,the causes of pavement diseases such as rutting,congestion pack,pushing and cracking in the existing Lanzhou BRT lanes were analyzed and summarized.And based on GeoStudio software to analyze the stress-strain situation of BRT lane pavement and the conduction state of solar radiation in the pavement material structure,the action forms of road pavement diseases such as rutting and congestion pack and the direct causes of the diseases are found.Through the longitudinal comparison of three pavement conditions in time and the transversal comparison of several conditions regarding subsidence and stress by the status quo,rutting-resistant asphalt,and changing the aggregate particle size ratio,it was found that the thermal insulation effect of rutting-resistant asphalt was better than that of marsupial asphalt surface material,while marsupial asphalt material performed better in terms of bending modulus and abrasion resistance.The comparative analysis of the solutions concluded that using marsupial asphalt as the surface layer,adding geotechnical material and prestressing layer in the middle of the surface layer and subgrade and implementing pre-cutting joints for the subgrade is a suitable improvement solution.