摘要
透过性坝是一种泥石流防治工程措施。对于少沙陡坡河道,透过性坝主要发挥其阻水功能。通过开展概化模型试验,研究陡坡河道透过性坝的阻水效应。在不同坝体透水率与上游流量下,测量透过性坝上游自由出流区、坝前壅水区和下游水流充分发展区的水深。建立了上游自由出流区与下游水流充分发展区的水深预测模型。基于能量方程,提出了坝前壅水区沿程水深计算模型与壅水区长度预测方法。结果表明:坝体透水率和上游流量是影响坝前水深与壅水范围的2个关键参量。当透水率越小或上游流量越大时,坝前水深越大且壅水范围也越大。下游水流充分发展区水深主要与下泄流量和河道过流条件有关。采用30组试验数据对上游自由出流区水深、坝前壅水区长度与沿程水深及下游水流充分发展区水深的预测公式进行验证,表明公式可准确预测上游自由出流区、坝前壅水区、下游水流充分发展区的水深及壅水长度。研究成果实现了透过性坝沿程水深、壅水区长度的准确预测,预测结果可为少沙陡坡河道中透过性坝的结构设计提供理论支撑。
Slit dam is an engineering measure for debris flow prevention and control.For a steep slope river with low sediment supply,slit dams mainly exhibit the effects on water retaining.A series of experiments were performed to investigate the water retaining effect of a slit dam in steep slope rivers.With different dam permeability and upstream discharges,the water depth in the free flow section upstream of the dam,the backwater section in front of the dam and the fully developed flow section downstream of the dam were measured.The prediction model for the water depth in the free flow section upstream of slit dam and in the fully developed flow section downstream of the dam had been established.The computational model for predicting water depth at different longitudinal positions in the backwater section and the method for predicting the length of backwater section had been proposed.The result indicated that flow depth and backwater length were affected primarily by the upstream discharge and dam permeability.As the permeability decreased or/and the upstream discharge increased,the water depth in front of the dam and the backwater region both increased.However,the water depth in the fully developed flow section downstream of the dam was primarily relevant to discharge flow and channel condition.The proposed method for predicting water depth in the free flow section upstream of the dam,the fully developed flow section downstream of the dam,the backwater section in front of the dam and backwater length were verified by using 30 groups of experimental data.The prediction had a good agreement with measurements,indicating that the proposed methods were capable of predicting the flow depth in the above sections and the length of backwater section.This study had achieved the accurate prediction of the flow depth at different longitudinal positions and the length of backwater section,which provided a theoretical basis for the structural design of the slit dam in the steep slope rivers with low sediment supply.
作者
桂子钦
刘超
黄尔
刘兴年
GUI Ziqin;LIU Chao;HUANG Er;LIU Xingnian(State Key Lab.of Hydraulic and Mountain River Eng.,Sichuan Univ.,Chengdu 610065,China)
出处
《工程科学与技术》
EI
CSCD
北大核心
2021年第6期175-184,共10页
Advanced Engineering Sciences
基金
教育部霍英东青年教师基金项目(171067)
教育部交流合作项目(教外司人文2020–703–3)
长江联合基金项目(U2040219)。
关键词
透过性坝
阻水效应
坝体透水率
壅水长度
计算方法
slit dam
water retaining effect
dam permeability
backwater length
computational methods
作者简介
桂子钦(1999—),女,硕士生.研究方向:河流泥沙.E-mail:aprilguiziqin@163.com;通信作者:刘超,E-mail:liuchaoscu@vip.qq.com。
