摘要
本文根据冲刷机理的不同,将采沙河床桥墩冲刷分成三部分:(1)采沙坑背水面边坡由于增加了水流比降容易形成溯源冲刷,(2)桥渡压缩水流过流断面增大水流挟沙力引起一般冲刷,(3)桥墩周围涡旋流造成局部冲刷。总的冲刷是三种冲刷的叠加。本文采用分步法计算了某河流采沙河床桥墩冲刷深度,各部分不同的冲刷机理采用相应的冲刷计算方法。结果表明采沙坑对桥墩安全的影响与沙坑尺度及其距大桥的距离有关。
According to the flow characteristics, the scouring around bridge piers can be divided into three parts ： 1. regression erosion due to the increase of hydraulic gradient occurred to the upstream side slope of the pits; 2. general erosion due to river cross section contraction by the piers; 3. local erosion due to vortexes around the piers. The total equilibrium scouring depth is the superposition of these erosions. The formulas for calculating these scouring are proposed respectively. An example is given for demonstration.
出处
《水利学报》
EI
CSCD
北大核心
2005年第7期835-839,共5页
Journal of Hydraulic Engineering
关键词
采沙坑
河床
溯源冲刷
一般冲刷
局部冲刷
scouring
bridge pier
sand pits
regression erosion
flow area contraction
vortex erosion
