【摘要】 考虑到堰塞坝不同内坡坡度和不同坝体级配对溃坝过程的影响,设计了11组溃坝试验进行研究,根据对溃坝过程的摄影记录,观测到溃坝过程的四个阶段,其中阶段Ⅲ的坝体侵蚀最为剧烈,阶段Ⅰ内坡被侵蚀,阶段Ⅱ溃口顶部被侵蚀,阶段Ⅲ外坡被侵蚀,阶段Ⅳ坝体形态达到稳定,库区水位逐渐达到恒定值;运用WYG-Ⅱ型水位测量系统,得到整个溃坝过程水库的实时水位数据,试验结果表明:内坡坡度越大,溃坝洪峰流量越大;不均匀系数越大,溃坝洪峰流量由于绕流掀沙现象的存在反而增大,而后随着粗沙越多,细沙隐蔽作用突出,溃坝洪峰流量减小。更多还原

【Abstract】 Seven dam break experiments were designed,with different inner slopes and gradation of grain building dam,to study the effect of conditions on the process of dam break.According to photography of dam break,four stages were observed,and the flow erosion of dam body was the most intense in stage Ⅲ.In stage Ⅰ,inner slope was eroded.In stage Ⅱ,the top of the breach was eroded.In stage Ⅲ,outer slope was eroded,and in stage Ⅳ,the shape of the dam body kept steadily and water level of reservoir gradually came to the constant.Using the WYG-Ⅱwater level measurement system,the real-time water lever data of the reservoir were obtained.The result of the experiments indicated that the peak discharge of dam break increases with theincrease of inner slope.If the nonuniformity coefficient is bigger,the peak discharge of dam break increases at first because of lee erosion,but decreases at last because of the conceal function.更多还原