多车道高速公路超高过渡段积水分布数值模拟与规律分析

为了揭示多车道高速公路超高过渡段积水分布规律，基于流体动力学理论，选取典型多车道高速公路超高过渡段设计参数，利用道路BIM设计软件建立了40组三维道路模型；分析了路面积水量和排水设施径流量的关系，建立了考虑排水设施与路面构造深度影响的降雨模拟方案；采用离散相模型和多相流模型耦合，模拟了降雨条件下的路面积水状态；分析了不同组合参数下的超高过渡段积水厚度数据，得到了合成坡度、道路宽度、降雨强度与超高渐变率对积水厚度的影响模式，计算了各车道最大积水厚度，分析了六车道、八车道高速公路积水横向分布规律。研究结果表明:积水厚度与合成坡度、超高渐变率负相关，与降雨强度、道路宽度正相关，其中降雨强度对积水厚度的影响最大，超高渐变率对积水厚度的影响最小；合成坡度为2.02%~8.54%，降雨强度为1~5 mm·min-1时，多车道高速公路超高过渡段最小积水厚度为0.58 mm，最大达到28.35 mm；当降雨强度为5 mm·min-1时，高速公路超高过渡段内外侧车道最大积水厚度差异明显，六车道由内侧车道到外侧车道的最大积水厚度比例为1.0∶3.1∶3.3，八车道为1.00∶0.96∶1.03∶1.36；多车道高速公路超高过渡段积水厚度峰值先出现在道路中间附近，然后向外侧移动，最大积水厚度一般出现在外侧车道。 

Numerical simulation and law analysis of water accumulation distribution at superelevation transition section of multilane expressway

In order to reveal the distribution law of water accumulation at the superelevation transition section of multilane expressway, the design parameters of the typical superelevation transition section of multilane expressway were selected based on the fluid dynamics theory, and the road design software BIM was used to establish 40 groups of 3D road models. By analyzing the relationship between road area water quantity and drainage facilities runoff, a rainfall simulation scheme considering the influence of drainage facilities and pavement structure depth was established. The discrete phase model and multiphase flow model were coupled to simulate the water accumulation state of road area under rainfall condition. By analyzing the water accumulation thickness data of superelevation transition section under different combination parameters, the influence modes of synthetic slope, road width, rainfall intensity and superelevation gradient rate on the water accumulation thickness were obtained. The maximum water accumulation thicknesses of each lane were calculated, and the horizontal distribution laws of water accumulation at six-lane and eight-lane transition sections were revealed. Analysis results show that the thickness of stagnant water is negatively correlated with synthetic slope and superelevation gradient rate, and positively correlated with rainfall intensity and road width. The rainfall intensity has the greatest influence on the ponding water thickness, and the superelevation gradation rate has the least influence on the ponding water thickness. When the synthetic slope is 2.02%-8.54% and the rainfall intensity is 1-5 mm·min-1, the minimum water thickness at the superelevation section of multilane expressway is 0.58 mm, and the maximum is 28.35 mm. When the rainfall intensity is 5 mm·min-1, the maximum water thicknesses of the inner and outer lanes at the superelevation transition section of the expressway are significantly different. The maximum water thickness ratio from the inner lane to the outer lane at the six-lane transition section is 1.0∶3.1∶3.3, and the ratio is 1.00∶0.96∶1.03∶1.36 at the eight-lane transition section. The peak value of water accumulation thickness at the superelevation transition section of multi-lane expressway first appears near the middle of the expressway and then moves outward, and the maximum water accumulation thickness generally appears in the outer lane. 3 tabs, 13 figs, 26 refs.