摘要
为研究堰塞坝坝体内部孔隙水压力对坝体的溃决发展过程的影响,通过水槽模型试验,在分析堰塞坝溃决过程的基础上,研究了堰塞坝溃决过程中孔隙水压力的变化过程。研究成果表明:根据溃口演化特征,可将堰塞坝的溃决过程分为3个阶段:坡面侵蚀阶段(Ⅰ)、溯源陡坎侵蚀阶段(Ⅱ)、粗化再平衡阶段(Ⅲ),其中,阶段Ⅱ发展最为剧烈;堰塞坝溃决过程中各测点孔隙水压力的变化过程均呈现先增后减的变化趋势,并存在明显的滞后现象;左右两侧的孔隙水压力呈“左小右大”的变化趋势,二者差值随溃口发展速率的加快而增加;上游孔隙水压力较下游明显增大,敏感程度也更高;蓄水期孔压可采用饱和非稳定二维渗流微分方程进行求解,整体变化趋势与实际值相符合,孔压增长速率呈先缓后陡趋势,最大孔压差绝对值为0.09 kPa。
In order to study the influence of pore water pressure inside the dam body on the development process of barrier dam failure.The flume model test was used to analysis the change process of pore water pressure during the barrier dam failure process.The research results show as follows.According to the evolution characteristics of dam breach,the process of dam breach can be divided into three stages:slope erosion stage(Ⅰ),tracing scarp erosion stage(Ⅱ),coarsening and rebalancing stage(Ⅲ).Among them,stage II has the most intense development.The change process of pore water pressure at each measuring point during the dam break shows a trend of first increase and then decrease,and there is a significant lag phenomenon;the pore water pressure on the left and right sides shows a trend of“left small and right large”,and the difference between the two increases with the acceleration of the development rate of the breach.The pore water pressure in the upstream was significantly higher than that in the downstream,and the sensitivity was also higher.The pore pressure in water storage period can be solved by saturated unsteady two-dimensional seepage differential equation.The overall trend was consistent with the actual value.The growth rate of pore pressure is slow first and then steep,and the absolute value of maximum pore pressure difference is 0.09 kPa.
作者
李霄
陈华勇
阮合春
俞昀晗
LI Xiao;CHEN Hua-yong;RUAN He-chun;YU Yun-han(Key Laboratory of Mountain Hazards and Surface Processes,CAS/Institute of Mountain Hazards and Environment,CAS,Chengdu 610041;University of Chinese Academy of Science,Beijing 100000,China;CAS Center for Excellence in Tibetan Plateau Earth Sciences,Chinese Academy of Sciences(CAS),Beijing 100101,China)
出处
《科学技术与工程》
北大核心
2022年第34期15304-15311,共8页
Science Technology and Engineering
基金
国家重点研发计划(2018YFE0100100)
国家自然科学基金(41771045)
中国科学院“西部之光”人才培养计划(2021160160)。
关键词
堰塞坝
溃决过程
孔隙水压力
变化规律
barrier dam
dam-break process
pore water pressure
change rule
