跨河圆柱形桥墩局部冲刷深度模拟试验研究  

Simulation test study on local scour depth of cylindrical bridge piers crossing rivers

作　　者：伯彦萍 史涵丹 彭芸 张洋 Bo Yanping;Shi Handan

机构地区：[1]贵州省水利科学研究院

出　　处：《生态文明新时代》2024年第3期107-111,共5页The New Era of Ecological Civilization

摘　　要：随着经济的发展,中国西南地区由于水系众多对于涉水桥梁的建设逐步增多。根据国内外资料统计,桥梁毁坏多是由于水毁造成的,而水毁事故中由桥墩冲刷造成的占比最大。本试验采用动床模型试验的方法研究桥墩模型冲刷规律和冲刷深度,采用粉煤灰模拟天然河沙,圆形有机玻璃管模拟圆柱形桥墩,共设置三组不同流速工况,分别为14.7cm/s、29.8cm/s、41.5cm/s。试验结果表明:1)当水流速度小于模型沙起动流速时,桥墩只产生一般冲刷;2)当水流速度大于模型沙起动流速时,桥墩两侧位置最先发生局部冲刷,且桥墩周围冲刷坑的范围随流速的增大而增大;3)桥墩产生局部冲刷后直到冲刷深度达到桥墩对河床的影响范围时局部冲刷停止,桥墩暴露后河床形态基本一致。With the development of the economy,the construction of water related bridges in the southwestern region of China is gradually increasing due to the numerous water systems.According to domestic and foreign data statistics,bridge damage is mostly caused by water damage,and the largest proportion of water damage accidents are caused by pier erosion.This experiment uses a moving bed model test method to study the scouring law and depth of the bridge pier model.Fly ash is used to simulate natural river sand,and circular organic glass tubes are used to simulate cylindrical bridge piers.Three different flow velocity conditions are set up,namely 14.7cm/s,29.8cm/s,and 41.5cm/s.The experimental results show that:1)when the water flow velocity is less than the starting velocity of the model sand,the bridge piers only produce general scouring;2)When the water flow velocity is greater than the starting velocity of the model sand,local erosion occurs first on both sides of the bridge pier,and the range of erosion pits around the bridge pier increases with the increase of flow velocity;3)After local erosion occurs on the bridge piers,it stops when the depth of erosion reaches the range of influence of the bridge piers on the riverbed.After the bridge piers are exposed,the riverbed shape is basically the same.

关 键 词：桥墩 冲刷 粉煤灰 试验研究 

分 类 号：U44[建筑科学—桥梁与隧道工程]