南水北调穿漳工程围堰深厚砂卵石层防渗施工

Impervious Element Construction of Cofferdam with Deep Sand and Gravel Overburden in Zhanghe River Crossing Project of South-to-North Water Diversion

南水北调穿漳围堰为临时性工程,所处位置砂卵石层深厚。对于其防渗施工,综合电力、工期、环境影响、防渗效果与投资等因素,最终选择了以防为主、防排结合的帷幕灌浆施工方案。施工中采取潜孔锤与岩芯钻机相结合的钻孔方法,采用自下而上分段、管口封闭、孔内循环的方式进行灌浆,保证了施工质量,加快了施工进度,确保了节点工期。

The cofferdam of Zhanghe River Crossing Project in South-to-North Water Diversion is a temporary project and locates on a deep overburden with sand and gravel. After considering the factors of power supply, schedule, environmental impact, seepage control effectiveness and investment, the seepage control system using curtain grouting is selected as the final program. The holes are drilled by combined utilization of DTH drilling and core-drilling machines in the construction, and the stage and circulation grouting is conducted from top to bottom. The construction quality and progress are guaranteed.