Scour around spur dikes and bridge abutments
Scour around spur dikes and bridge abutments
复制标题
冲刷丁坝和桥台周围
DOI：
10.1080/00221680109499841
复制
发表时间：
2001
影响因子：
2.3
通讯作者：
K. G. R. Raju
中科院分区：
文献类型：
--
作者：
U. C. Kothyari;K. G. R. Raju
冲积河流直堤及桥台冲刷深度的真实估算对其基础的安全经济设计具有重要意义。以前的研究人员已经开发出程序，利用设计流量来确定堤台和直堤稳定水流中的设计冲刷深度。然而，设计排放所需的时间冲刷到其全部潜力通常比它运行的时间大得多。因此，计算冲刷深度的时间变化对设计也很重要。发现桥墩、桥台和直堤的冲刷过程是相似的，只是桥台或直堤上游的河道壁所引起的边界层效应比桥墩的冲刷作用要小。因此，在本研究中，我们提出了类似桥墩的概念。在相似的水力条件下，类似的桥墩与给定的桥台或直堤具有相同的平衡冲刷深度。与桥台/直堤和桥墩周围水流阻力有关的参数对建立模拟桥墩直径的关系是有用的。然后以模拟墩的尺寸作为墩直径，利用墩冲刷方程计算了柱堤和桥台冲刷深度的时间变化和平衡冲刷深度。所得到的结果是用几个研究者的实验室数据对清水和活床冲刷条件进行验证。
Realistic estimation of scour depth around spur dikes and bridge abutments in alluvial rivers is important for safe and economic design of their foundations. Procedures have been developed by previous investigators for determination of design scour depth in steady flows at abutments and spur dikes by making use of the design discharge. However, the time required by the design discharge to scour to its full potential is generally much larger than the time for which it runs. Therefore, computations on temporal variation of scour depth are also important for design purposes. Scour processes at bridge piers, abutments and spur dikes have been found to be similar except that the boundary layer effect induced by the channel wall upstream of the abutment or spur dike causes less scour around these as compared to the case of piers. In the present study, therefore, the concept of an analogous pier is developed. The analogous pier would have the same equilibrium scour depth as the given abutment or spur dike under similar hydraulic conditions. The parameters relating to drag due to flow around abutment/ spur dike and bridge pier have been found to be useful in establishing a relationship for the diameter of the analogous pier. The temporal variation of scour depth and the equilibrium scour depth at the spur dike and the abutment are then computed using pier scour equations with size of the analogous pier being taken as the pier diameter. Results obtained are verified using laboratory data of several investigators for both clear-water and live-bed scour conditions.