第七章路基路面排水设计课稿.ppt

复习 1、概述：分类 2、挡土墙的构造与布置 ：构造 3、挡土墙土压力计算：主动土压力 4、挡土墙设计原则：极限状态分项系数法 5、重力式挡土墙设计：验算 排水式沥青路面 三、路面内部排水 路面内部排水系统的设计通常需满足三方面的要求： 各项设施应具有足够的泄水能力，排除渗入路面结构内的自由水； 自由水在路面结构内的渗流时间不能太长，渗流路径不能太长； 排水设施要有较好的耐久性。 由沿路面边缘设置由透水性填料集水沟、纵向排水沟、横向出水管和过滤织物组成的边缘排水系统，该系统是将渗入路面结构内的自由水，先沿路面结构层间空隙或某一透水层次横向流入纵向集水沟和排水管，再由横向出水管排引出路基。 该方案主要用于基层透水性小的水泥混凝土路面。 便于将面层-基层-路肩界面处积滞的自由水排离路面结构。 四、边缘排水系统 边缘排水系统（cm） a) 新建路面边缘排水系统；b)改建路面边缘排水系统 1-?面层；2-基层；3-垫层；4-路肩面层；5-集水沟； 6-排水管；7-出水管；8-反滤织物；9-回填路肩面层 * 设置边缘排水设施 * 边缘排水设施的施工 基层排水系统是直接在面层下设置透水性排水基层，在其边缘设置纵向集水沟和排水管以及横向出水管等，组成排水基层排水系统。 采用透水性材料做基层，使渗入路面结构内的水分，先通过竖向渗流进入排水层，然后横向渗流进入纵向集水和排水管，再由横向出水管排引出路基。 五、排水基层的排水系统 排水基层排水系统 1-面层；2-排水基层；3-不透水垫层；4-路肩面层或水泥混凝土路肩面层；5-集水沟；6-排水管；7-出水管；8-反滤织物；9-路基 排水效果优于边缘排水系统，适用于新建路面。 排水层的透水性材料可以采用经水泥或沥青处治的开级配碎石集料。 * This photo illustrates ponding of water on the road caused by a localized settlement. Depressions in the road allow water to stand on the surface. This can cause stripping on the AC layers and water can slowly seep into the pavement and saturate the underlying layers thereby accelerating distress developing. This photo illustrates a high-severity pothole filled with water which accelerates the surrounding cracking and increases its size. This photo illustrates the pumping of water and fines from the transverse joint as a rapidly moving truck load is applied. Pumping and erosion of the underlying layers are the most prevalent moisture-related problems associated with jointed PCC pavements. Pumping was disastrous at the AASHO Road Test, where virtually every section that failed was preceded by excessive pumping of the base course. Faulting is the most serious cause of roughness in jointed PCC pavements. This photo illustrates water and fine materials pumping from the longitudinal joint between the pavement and the shoulder. Wide openings at the joint provide an escape route for water on bathtub sections. This is a common occurrence after heavy rains or during spring thaw periods. Faulting is a direct result of p