RCC Dams - Inclined Internal Drain Holes
A common design feature to most Roller Compacted Concrete (RCC) dams is the internal drainage system. This system basically consists of one or more drainage galleries located near the upstream face of the dam with vertical drain holes drilled between them. These vertical drain holes generally extend from the base of the dam up to the dam crest to provide a complete internal drainage system by draining water which may seep into and between the RCC placement joints. Their primary purpose is to reduce potential uplift forces which could develop along the RCC placement joints. A secondary, and basically aesthetic benefit, is to reduce the likelihood that water migrates to the downstream face of the dam and produces an undesirable effect. Common practice is to drill internal drain holes in a vertical position. Because of this orientation, these drain holes only cross the RCC placement joints. Consideration could be given to drilling these holes with a variable inclination, along the plane of the drainage galleries. These inclined drain holes would also cross the vertical monolith joints as well as any crack(s) which may develop within the monolith, thus significantly enhancing their use. This would be a practical and inexpensive means to improve the seepage control of RCC dams as well as improving the overall performance of the dam. Such a detail is being considered in the detailed design of the RCC dam for the Ban Chat HPP currently under construction.
crack seepage drain holes vertical holes inclined holes
George Casagran Pham Nguyen Hung
SNC-Lavalin Inc, 455 Rene-Levesque Blvd. West, Montreal, Canada H2Z 1Z3 Power Engineering Consulting Compay No.1 (PECC 1), Thanh Xuan District, Ha Noi, Vietnam
国际会议
第五届碾压混凝土坝国际研讨会(The Fifth International Symposium on Roller Compacted Concrete(RCC))
贵阳
英文
149-153
2007-11-02（万方平台首次上网日期，不代表论文的发表时间）