雨天公路水膜厚度模型验证及行车安全性分析

针对雨天行车道路表面产生水膜,易使车辆打滑发生交通事故的问题,采用人工模拟降雨试验,获得了水泥混凝土路表水膜厚度回归方程,验证了国内外现有水膜厚度计算模型。结果表明：路表水膜厚度随降雨强度和排水长度的增大而增大,随路面坡度的增大而减小；相同条件下,水泥混凝土路表水膜厚度值高于沥青路面水膜厚度值,其原因主要是水泥混凝土的亲水性导致路表水分子流动阻力增大,水分子积聚增多,使水膜厚度增大。对西安地区不同暴雨重现期下高速公路水膜厚度值进行计算,结果表明在五年重现期暴雨强度1.954 mm?min-1下,路表水膜厚度值不超过滑水速度发生时的临界水膜厚度值2.35mm,设计时速80 km.h-1可保证雨天行车安全。

Verification of Water Film Depth Model and Analysis of Highway Traffic Safety in Rainy Day

For the water film on the rainy road surface which is easy to make the vehicle slip causes traffic accidents. The regression equation of water film thickness of cement concrete road surface was obtained by artificial simulated rainfall test, and the existing calculation models of water film thickness are verified. The results show that The thickness of the surface water film increases with the increase of rainfall intensity and drainage length, and decreases with the increase of slope; Under the same conditions, the thickness value of cement concrete road surface water film is higher than that of asphalt pavement. The reason is that the hydrophilicity of cement concrete leads to the increase of water resistance of water surface, leads to the accumulation of the surface water molecules increases. The results show that under the rainstorm intensity of 1.954 mm.min-1 in the five-year reconstruction period, the thickness of the surface water film does not exceed the critical water film thickness 2.35mm when the water-skiing velocity occurs. The design speed of 80 km.h-1 can ensure the safety of rainy days.