摘要
渗流特性是影响大坝安全的主要因素,尤其对土石坝更为重要。以某水库均质土坝为例,对实测测压管数据进行分析,同时采用有限单元法对大坝典型断面开展稳定和瞬态典型工况下的大坝渗流场计算分析,获得孔压分布规律,并与实测结果进行比较。结果表明,测压管距上游坝脚距离与测压管水位呈负相关,测压管水位变化趋势与库水位变化趋势基本一致;等水头线在材料分区处偏折,在防渗墙处密集,墙后浸润线和出逸点位置降低;实测浸润线与理论计算值吻合较好,均与库水位发生同步升降,具有较好的相关性;各工况下大坝逸出点渗透坡降均小于允许坡降,坝体渗流稳定性满足要求。
Dam seepage is one of the main factors endangering dam safety,especially for earth-rock dam.Taking the homogeneous earth dam of a reservoir as the example,this paper analyzes the measured piezometer data,and calculates and analyzes the seepage field of the typical dam section under typical stable and transient working conditions by the finite element method for obtaining the pore pressure distribution law,and comparing it with the measured value.The results show that:The distance between piezometer and upstream dam toe is negatively correlated with piezometer water level,and the change trend of piezometer water level is basically consistent with that of reservoir water level;The isopotential line is deflected at the material partition,and dense at the cutoff wall,and the phreatic line and release point below the cutoff wall lower;The measured and theoretical values of phreatic line coincide well,which increase or decrease with the reservoir water level with good correlation;The seepage gradient at the release point under each working condition is less than the allowable gradient,and the seepage stability of the dam meets the requirements.
作者
刘凤茹
波兰汗·开肯
詹达美
LIU Fengru;BOLANHAN·Kaiken;ZHAN Damei(Shenzhen Guanghuiyuan Environment Water Co.,Ltd.,Shenzhen 518020,China;College of Water Conservancy and Hydropower Engineering,Hohai University,Nanjing 210098,China)
出处
《人民珠江》
2021年第8期69-73,共5页
Pearl River
基金
广东省水利科技创新项目(2020-5)。
关键词
土坝
渗流场
浸润线
渗透坡降
earth dam
seepage field
phreatic line
seepage gradient
