水文地质工程地质2011，Vol.38Issue(1)：40-45,64,7.
金沙江其宗河段河床深厚覆盖层特征及其工程效应研究
A study on the characteristics of deep overburden in Qizong segment of Jinsha River and its engineering effects
摘要
Abstract
Overburden of 60 ～ 120m deep is developed in the Qizong segment of Jinsha River. The deep overburden can be divided into three layers upward. Pebble and gravel intercalated with minor fine sand or silty clay with the thickness of 11.1 ～ 33m at the bottom of the riverbed; a layer of fine sand, silty clay,pebble and gravel which with the thickness of 10.04 ～ 35m in the middle of the riverbed; coarse lenses of the drift (blocks), pebble (broken) and gravel layer with the thickness of 9. 5 ～59m in the upper part. Sand lens are widely distributed in the deep overburden. The maximum buried depth is 83. l m, the maximum thickness is 29.4m, and the minimum thickness is only 0. 5m. The thickness of the sand lens is generally within 5m. Studies show that the sand lens is not formed by the accumulation of lacustrine, but is formed by accumulation of the relatively still water environment and the normal river floodplain. By indoor sampling tests, it shows that coarse-grained soil (boulder -pebbles accumulation, etc. ) in the overburden of the river bed is relatively strong and hard, fine-grained soil in the lower place is excess consolidated, but nonliquefaction. Fine sand lens at the upper are relatively weak, so it is possible to be liquefied under an earthquake. The engineering effects can be concluded that because of the bad geological conditions it is only suitable for rock-fill dam, the excavated volume is huge, the sand layer treatment depth is large and impermeable treatment is quite difficult.关键词
深厚覆盖层/发育特征/工程效应/金沙江分类
天文与地球科学引用本文复制引用
王运生,邓茜,罗永红,王自高,高建,吴俊峰,孙刚..金沙江其宗河段河床深厚覆盖层特征及其工程效应研究[J].水文地质工程地质,2011,38(1):40-45,64,7.基金项目
国家自然科学基金项目(中国西部深切河谷谷底卸荷松弛带形成机理及其工程效应研究,40472143/D0214) （中国西部深切河谷谷底卸荷松弛带形成机理及其工程效应研究,40472143/D0214）
