坝体土料黏粒质量分数对均质土坝漫顶溃决过程的影响

为了研究坝体土料黏粒质量分数对均质土坝漫顶溃决过程的影响,建立了描述均质土坝溃坝溃口发展规律的溃坝数值模型,对实体溃坝案例进行了反馈分析,验证了模型的合理性,并利用该模型重点研究了坝体土料黏粒质量分数对均质土坝溃口发展规律和洪水流量过程的影响。结果表明:坝体土料的黏粒质量分数对均质土坝的溃口发展规律、最终溃口形状以及溃口洪水流量过程具有明显影响,土体黏粒质量分数越高,其临界起动流速越大,冲蚀率越小,均质土坝溃口的发展速率越慢,溃口边坡的失稳坍塌临界深度越大,从而导致最终溃口形状也越小,相应地溃口洪峰流量及最大下泄水量也越小,溃口洪峰流量出现的时间越迟。

Influence of clay content on overtopping breach process of homogeneous earth dam

In order to study the influence of clay content on the overtopping breach process of a homogeneous earth dam,a numerical model describing the principle of the breach development of the homogeneous dam was developed.The back analysis of a breach case showed that the model was reasonable.The model was employed to study the influence of clay content on the dam breach and the hydrograph of flood flow.The results show that the clay content has a significant influence on the dam breach,the breach shape,and the hydrograph of flood flow.The higher the clay content is,the larger the critical incipient velocity and the critical collapse depth of the breaches are,the smaller the erosion rate,the breach development rate,the breach shape,and the hydrograph of flood flow are,and the later the time for the peak discharge is.