IAHR, founded in 1935, is a worldwide independent member-based organisation of engineers and water specialists working in fields related to the hydro-environmental sciences and their practical application. Activities range from river and maritime hydraulics to water resources development and eco-hydraulics, through to ice engineering, hydroinformatics, and hydraulic machinery.
Log On
About IAHRDirectoryCommitteesMy IAHRNews & JournalseLibraryeShopEventsJoin IAHRWorld CongressDonate
spacer.gif eLibrary
spacer.gif eLibrary
You are here : eLibrary : IAHR World Congress Proceedings : 35th IAHR Congress - Chengdu (2013) : THEME 7 - WATER RESOURCES AND HYDROINFORMATICS : A Study on Optimal Depth of Impervious Wall in Deep Overburden under Earth Dam Basement
A Study on Optimal Depth of Impervious Wall in Deep Overburden under Earth Dam Basement
Author : Xie Xinghua, Lu Jun, Tan Yefei and Zhao Jianjun
There are plenty of rivers with prolific water energy in west China. These rivers are located in high mountains with river bed of sands and gravels that is called deep overburden. Anti-seepage structures in basement are needed to cut-off the seepage as earth dams are built on river bed with deep overburden. In China, concrete impervious wall is used as this kind of anti-seepage structures. Concrete impervious wall is built to cut-off the seepage path in river bed when the overburden is in a depth of no more than 80m. But in other scenarios such as the depth of overburden is more than 90m, for instance it is more than 140m in depth in the dam base of Yele hydropower station, it is difficult to build the cut-off style imperious wall because its qualification is out of control in such deep overburden. So it is necessary to study the effectiveness of suspended imperious wall in deep overburden dam base and to find the best depth considering the anti-seepage demand and its economical. The best depth of impervious wall is studied following the basic principles of seepage. It shown that the deeper the impervious wall, the smaller of the average seepage gradient in the seepage path, and the smaller of the uplift pressure to the dam base. The relation curve iss not linear between depth of impervious wall and its effectiveness. There iss an identified depth of the impervious wall. The effectiveness is significantly when the depth of the impervious wall is lower than the identified depth. When it goes upper than the identified depth, the affecting becomes smaller, and a most economical depth of the suspended impervious wall in deep overburden. As the seepage gradient is kept in the safe range, the most economical depth would be the best depth of the suspended impervious wall. And it is clear that the best depth is affected by the overburden composition and the water head pressure.
File Size : 367,599 bytes
File Type : Adobe Acrobat Document
Chapter : IAHR World Congress Proceedings
Category : 35th IAHR Congress - Chengdu (2013)
Date Published : 19/07/2016
Download Now