基于“移动水坝”的高速公路雨天行车安全性研究  

Traffic Safety of Rainy Day Expressway with “Moving Dam”

作　　者：乔建刚 吴艳霞[1] 张雪洁 QIAO Jian-gang;WU Yan-xia;ZHANG Xue-jie(School of Civil and Transportation,Hebei University of Technology,Tianjin 300401,China;Tianjin Traffic Engineering Green Materials Technology Research Center,Hebei University of Technology,Tianjin 300401,China)

机构地区：[1]河北工业大学土木与交通学院,天津300401 [2]河北工业大学天津市交通工程绿色材料技术研究中心,天津300401

出　　处：《中国公路学报》2018年第4期304-311,共8页China Journal of Highway and Transport

基　　金：国家自然科学基金项目(51108011);国家安全生产监督总局安全生产重特大事故防治关键技术科技项目(hebei-0009-2017AQ);天津市交通运输委科技项目(2016-A08)

摘　　要：为了减少雨天交通安全隐患,保障高速公路行车安全,根据雨天高速公路实际行车状态、路面径流特点和车辆水膜相互作用探究雨天安全行车速度。首先,提出"移动水坝"概念,并分析"移动水坝"现象出现的原因和形成机理;依据水力学基本理论探究"移动水坝"现象中水膜厚度和车辆滑水限速值的变化规律;然后,利用Fluent软件仿真车辆对水流的阻挡作用,依据外侧车道大车行车间距的水压力探究连续"移动水坝"形成的条件,并确定外侧车道大车在不同行驶速度下相应的临界车头时距;最后,应用流体力学原理仿真分析车辆行驶速度和水膜厚度与轮胎受到的动水压力之间的关系,确定不同降雨强度下内侧车道小客车的滑水限速值。研究结果表明:雨天在高速公路外侧车道行驶的大车会对路面径流产生阻挡作用,出现"移动水坝"现象;"移动水坝"作用下水膜厚度较正常排水状态下增加,导致内侧车道行驶的小客车滑水限速值降低;设定试验条件下外侧车道大车间距40m时,两车的水坝作用连续,增加大车车头时距可以减弱连续"移动水坝"作用;车辆行驶过程中轮胎受到的动水压力随水膜厚度及行驶速度的增加而增大,小客车在"移动水坝"作用下发生滑水的概率增加,根据轮胎动水压力值和滑水值确定不同降雨强度对应的临界滑水速度,可相应作为雨天高速公路小客车行驶速度限值。To ensure the safety of expressway traffic and reduce the hidden dangers in terms of traffic safety under rainy conditions, the distance of the vehicle and the safety speed on an expressway during a rainy day were explored according to the actual traffic conditions and road surface runoff characteristics and their interaction. The concept of a ＂moving dam＂ was put forward for the first time, and the causes and formation mechanism of a ＂moving dam＂ phenomenon were analyzed. The relationship between the water film thickness and the critical velocity of hydroplaning during a ＂moving dam＂ was obtained through an analysis of the tire force. Using Fluent to simulate the obstruction of the vehicle to water, the critical distance of the outer lane vehicle at different speeds was determined according to the formation conditions of a continuous ＂moving dam＂. By using the principle of fluid mechanics, the relationship between the vehicle speed and water film thickness, and the hydrodynamic pressure of the tire, were analyzed to determine the critical velocity of hydroplaning of the inner lane car under different rainfall intensities. The results indicate that, under rainy conditions, the vehicles on the outer lane of expressway have a blocking effect on the road runoff, resulting in a ＂moving dam＂. Unlike a normal drainage state, under the action of a ＂moving dam＂, the thickness of the water film increases and the critical velocity of the hydroplaning of the inside lane car decreases. Under the set conditions, when the distance between the vehicles is less than 40 m, the dams of the two vehicles are continuous, and an increase in the time headway can weaken the role of a continuous ＂moving dam＂. During the course of the vehicle, the hydrodynamic pressure of the tire increases with an increase in the thickness of the water film and the operating speed of the cars. The probability of cars sliding over water under the action of a ＂moving dam＂ increases. According to the hydrodynamic pressure of

关 键 词：交通工程 移动水坝 Fluent仿真 临界滑水限速 临界车头时距 水膜厚度 

分 类 号：U491.25[交通运输工程—交通运输规划与管理]