黄金坪水电站基坑大流量条件下抽排水施工设计

Design of pumping and draining of foundation pit for Huangjinping Hydropower Station under condition of large flow rate

黄金坪水电站上、下游围堰均建于深覆盖层上,在基坑开挖过程中,上下游围堰渗水量大,给基坑经常性抽排水施工造成极大困难。本文对流量计算、泵站施工进行了全面分析,提出经常性抽排水施工设计措施,在保证正常施工前提下有效解决了大流量条件下基坑经常性抽排水施工的难题。

As both the upstream and downstream cofferdams for the construction of Huangjinping Hydropower Station are constructed on a deep overburden,a great difficulty from the regular pumping and draining of the foundation pit is caused by the large seepages from the cofferdams during the excavation of the pit. Based on an overall analysis made on the calculation of flow rate and the construction of pumping station,the designed measures for the regular pumping and draining are proposed herein,and then the difficulty from the regular pumping and draining for the foundation pit under the condition of large flow rate is overcome under the premise of ensuring the normal construction concerned.