沥青路面集中排水影响分析与响应识别

如何通过路侧排水口将路面径流快速排出是路面集中排水设计需要解决的关键问题。为了分析路面宽度和坡度变化对集中排水的影响，准确识别集中排水条件下排水口泄流能力与影响范围，基于水动力学理论得到路面二维浅水方程，考虑降雨、地形、流体阻力等因素对路面径流变化的影响作用，建立路面径流运动变化分析模型，并采用实际观测数据对模型参数进行验证。结合实际工程建立路面数字高程模型，在设计降雨条件下，分析路幅宽度增加和坡度变化对路面径流深度分布和路面集中排水能力的影响作用，对比不同坡度组合下的路面排水量，并识别路侧排水口影响范围。研究结果表明：路面排水量、路面径流流速、路面径流汇流时间是路面集中排水研究需要考虑的重要方面；采用路缘石开口进行集中排水时，路侧缘石对路面径流的汇流过程具有明显的拦阻作用，路肩范围内出现壅水现象；较低的路缘石高度可以减少路侧壅水对外侧行车道的不利影响，进而提高路面行车安全；对于模拟条件下（横坡2%）的固定排水口布置形式，存在相应的排水最优路面纵坡值范围（1%~1.2%）；路面径流的汇流方向与路面合成坡度方向不一致，当路面宽度增加时，路面汇流路径增长显著，路宽24.5 m时，路面径流没有就近从排水口流出，汇流路径沿道路纵向超过70 m。

Influence Factors and Response Identification for Asphalt Pavement Central Drainage

How to discharge pavement runoff using outlets is the key problem to be solved for pavement drainage system designs, such that the influence of the pavement width and slope on the central drainage can be analyzed and the central drainage capacity and influence area of the outlets can be recognized. Pavement two-dimensional shallow water equations were obtained based on hydrodynamic theory. The analysis model of the pavement runoff variation was proposed considering the influence of rainfall, terrain, fluid resistance, and other factors. The model parameters were verified by field monitoring data. A digital elevation model of the pavement was obtained according to practical engineering. Under the design rainfall condition, the distribution of the pavement runoff depth and the central drainage capacity was analyzed under the influence of pavement width increase and slope variation. The pavement discharge was compared when the slope combinations were different. The influence range of the pavement drainage outlets was also identified. The results show that the pavement drainage, runoff velocity, and confluence time are the significant parts that need to be considered in the research on the pavement central drainage. Regarding the central drainage by curbs, the curbs have an obvious interception effect on the pavement runoff, and the backwater phenomenon occurs in the shoulder area. The lower curb's height can reduce the adverse effect from the backwater on the lateral lane for improving driving safety. Meanwhile, the best longitudinal gradient range (i.e., 1%-1.2%) for pavement drainage can be observed for the simulated condition (i.e., the cross slope is 2%) of the fixed outlet layout form. The pavement runoff direction is not consistent with the resultant gradient. The length of the flow route increases when the pavement width broadens. The pavement runoff does not flow out from the nearest outlet when the width is 24.5 m. Moreover, the runoff route length exceeds 70 m in the longitudinal direction.