Overtopping breaching of cohesive homogeneous earth dam with different cohesive strength  

作　　者：ZHANG JianYun LI Yun XUAN GuoXiang WANG XiaoGang LI Jun 

机构地区：[1]Nanjing Hydraulic Research Institute,Nanjing 210029,China [2]State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering,Nanjing 210029,China

出　　处：《Science China(Technological Sciences)》2009年第10期3024-3029,共6页中国科学（技术科学英文版）

基　　金：Supported by National Key Technology R&D Program in the 11th Five-year Plan of China (Grant No. 2006BAC14B00)

摘　　要：In consideration of the range of clay content of Chinese earth dams, the world's highest prototype tests have been made to research on the effects of cohesive strength of filling of cohesive homogeneous earth dam on breach formation. Three breach mechanisms were presented, they were the source-tracing erosion of dam body with the form of "multilevel headcut", "two-helix flow" erosion of dam crest and collapse of breach sidewalls due to instability. It can be concluded that the cohesive strength of filling of earth dam has great effect on breach formation. When the cohesive strength is bigger, the breach process becomes slower, and the peak outflow and the final width and depth of breach become smaller. The main character of the breach formation is head cutting and dumping collapse. When the cohesive strength is smaller, the breach process becomes faster, and the peak outflow, the final width and depth of breach become bigger. The main character of the breach formation is single level head cutting and shearing collapse.In consideration of the range of clay content of Chinese earth dams, the world’s highest prototype tests have been made to research on the effects of cohesive strength of filling of cohesive homogeneous earth dam on breach formation. Three breach mechanisms were presented, they were the source-tracing erosion of dam body with the form of “multilevel headcut”, “two-helix flow” erosion of dam crest and collapse of breach sidewalls due to instability. It can be concluded that the cohesive strength of filling of earth dam has great effect on breach formation. When the cohesive strength is bigger, the breach process becomes slower, and the peak outflow and the final width and depth of breach become smaller. The main character of the breach formation is head cutting and dumping collapse. When the cohesive strength is smaller, the breach process becomes faster, and the peak outflow, the final width and depth of breach become bigger. The main character of the breach formation is single level head cutting and shearing collapse.

关 键 词：EARTH DAM breach mechanism headcut two-helix FLOW 

分 类 号：TV698.1[水利工程—水利水电工程] TV64