生产堤溃口展宽过程的概化模型试验研究  

Investigation into lateral widening process of farm dike breach using a sketched physical model

作　　者：果鹏[1] 夏军强[1] 周美蓉[1] 张晓雷[1,2] GUO Peng;XIA Junqiang;ZHOU Meirong;ZHANG Xiaolei(State Key Laboratory of Water Resources and Hydropower Engineering Science,Wuhan University,Wuhan 430072,China;School of Water Conservancy,North China University of Water Resources and Electric Power,Zhengzhou 450046,China)

机构地区：[1]武汉大学水资源与水电工程科学国家重点实验室,湖北武汉430072 [2]华北水利水电大学水利学院,河南郑州450046

出　　处：《水科学进展》2020年第2期249-259,共11页Advances in Water Science

基　　金：国家自然科学基金资助项目(51725902,51579186)。

摘　　要：为研究生产堤溃口横向展宽过程的发展规律,以黄河下游生产堤土体为材料,开展概化模型试验,分析溃口处水深、流速、流量以及溃口宽度的变化。试验结果显示,溃口横向展宽的机理主要表现为水流冲刷堤身下层土体伴随上层悬臂土体发生绕轴崩塌;随着溃口展宽,堤前水深持续下降但下降速率逐渐减小,溃口流速呈先增大后减小的趋势,流速峰值约为1.1 m/s;随着主槽流量增加,溃口宽度发展至0.7 m时,溃口的水深、泄流流量、流速、展宽速率均有所增加。基于对溃口展宽的影响因素分析,提出溃口横向展宽速率的计算关系式,计算溃口展宽过程与实测值符合较好。研究结果不仅有助于生产堤展宽机理及发展规律的研究,还可为数学模型的建立与验证提供参考资料。In order to investigate the lateral widening process of farm dike breach,a generalized physical model was constructed.Farm dikes with different soil properties in experiments were built using the soil excavated from a prototype farm dike located in the Lower Yellow River.The variation processes of hydraulic characteristics and breach widths were measured and analyzed.Experimental results show that the lateral widening mechanism during the process of dike breach was clarified by two aspects,including the lateral erosion of the dike soil below the water level,and the collapse of the dike soil above the water level.The flow velocity at breach site increased first and then decreased,with a peak value of 1.1 m/s.The water depth kept decreasing,but the decreasing rate gradually became smaller.Water depths,breach velocities and discharges,and lateral widening rates increased with an increase of inlet discharge.An empirical formula to calculate the lateral widening rate was proposed based on the analysis of factors influencing the farm dike breach,and the calculated widening process agreed well with the measured process.These results can provide experimental data not only for the research on the lateral widening process of farm dike breach,but also for the validation of numerical models.

关 键 词：生产堤溃决 概化模型试验 溃口宽度 展宽速率 

分 类 号：TV122.4[水利工程—水文学及水资源]