英文篇名
Case Study on Curtain Grouting of Dam Foundation in Karst Limestone
作者
陳蒼賢、黃凱旋、薛仲修、李民政
關鍵字
El Cajón 壩、浴缸型灌漿幕、岩溶石灰岩、拱壩基礎處理
摘要
高度226m的宏都拉斯El Cajón壩為世界著名的高拱壩,壩基座落於岩溶石灰岩地層,有四個高角度主要斷層通過壩址,水庫佈設獨一無二的「浴缸」型隔幕,從石灰岩壩基延伸而出,進入上游的火山岩,灌漿幕總面積達530,000m2。自從1985年水庫完工初始蓄水以來,曾發生壩基上揚水壓和總滲漏量顯著激增狀況,已進行三次修復性隔幕灌漿工程,第一次是在1989年完成,第二次是在1995年完成,2014~2017年的MOS特別維修工程為其第三次補強灌漿,係針對N45°E斷層及岩溶石灰岩地層大孔隙處理、高水頭以及高湧水孔段之艱困條件下進行灌漿作業,成功地將壩座滲漏量降低。
英文摘要
The Honduras El Cajón dam, with a height of 226m, is a world famous high arch dam. Its foundation sits on the Karst Limestone bypassing four high-dip-angle faults. The unique ”bathtub” type curtain grouting layout of the reservoir stretches from the Limestone to the upstream Igneous rock, occupying a total area of 530,000 m2. Both the uplifting water pressure and seepage quantity acting on the dam foundation have been increased abruptly since 1985, when the reservoir project was completed and in service to retain water. Since then, the grouting works to repair the curtain have been conducted for three times. The first and second works were completed in 1985 and 1995, respectively, while the third work, known as the MOS repair project, was proceeded between 2014 and 2017. Specifically, the third grouting work focused on the N45°E fault, big fissure, large water head condition, and huge groundwater inflow in the Karst Limestone. The seepage quantity in the dam foundation was successfully reduced at the end.