摘要
本文根据细沙多河流的原型河床边界条件,通过物理概化模型试验,较系统地研究了细沙河床桥墩附近水位变化、冲刷过程及冲刷坑形态等问题后,发现当局部冲刷停止时,床沙中径相应变粗1.5——2.5倍,而且实验曲线进一步反映了桥墩冲深随行进流速增加而加大的变化趋势。此外文中还对多沙细沙河流工程附近的局部河床冲刷的试验模拟充法进行了深入探讨,并对有关计算公式进行了检验与分析。
In this paper, firstly, according to the bed conditions of mototype river with fine and more sand, by means of the physical model tests, there were to investigate systematically the variation of water level, scouring proless and configuration of local scour. Based on this, it has been found out that the medium diameter of bed sand is relately 1.5—2 times courser than that originally, when the local scour stops. Furthermore, the experimental curves progressively indicates that the scouring depth hear bridge piers increases with the increasing of the approach velocity. In addition, the modeling methods, in the tests for local bed scour hear the river projects, deeply discussed. Eventually, some relevant callulating formulas are verified and analyzed.
