摘要
“陡坎”式发展是黏性土均质坝漫顶溃决的重要机理。开展了7组黏性土均质坝”陡坎“移动速度室内实体物理模型试验，旨在揭示黏性土均质坝“陡坎”式发展的基本规律。试验结果显示，相同压实度条件下，含水量越大，陡坎移动速度越慢，当含水量达到最优含水量后，陡坎移动速度非常缓慢（本文试验含水量范围为10％～18％）。压实度越小，陡坎移动速度越快。基于土石坝“陡坎”式冲蚀力学机理，建立了坝体土“起动摩阻流速”U＋c与坝体材料抗冲能力综合系数C之间的关系，实例验证显示，提出的预报模型能够明显提高”陡坎”移动速度的预测准确度。
The ＂headcut＂ is an important mechanism of cohesive homogeneous embankment failed by overtopping. 7 physical model tests of the headcut migration rate were conducted to study the rules of the process of the headcut. According to the result that the larger the water content is, the more slowly the headcut migration rate is when the degree of compaction is the same. As the water content exceeds the optimum moisture content, the rate is very low （the water content of embankment is 10%-18% in this paper）. The smaller the degree of compaction is, the faster the headcut moves. In this paper, the relationship between the ＂threshold friction velocity＂ U＊c and material rate parameters C is established based on the headcut mechanism. Through the validation of examples it can be seen this model can significantly improve predicating accuracy of the headcut migration rate.
出处
《中国农村水利水电》
北大核心
2010年第2期102-104,107,共4页
China Rural Water and Hydropower
基金
"十一五"国家科技支撑计划项目"水库大坝安全保障关键技术研究"(2006BAC14B00)
江苏省博士后科研资助项目"均质黏性土坝漫顶溃决机理试验研究"(0802074C)
关键词
陡坎
材料综合系数
起动摩阻流速
headcut
material rate parameters
threshold friction velocity
