天生桥一级水电站围堰工程的防渗处理

Antiseepage Treatment for Cofferdam Engineering of Tianshengqiao Ⅰ Hydropower Station

为了使围堰具有足够的防渗性,根据堰体结构和堰基地质的情况,选用高压喷射注浆技术,建造防渗板墙的施工方案。防渗板墙沿围堰轴线布置,它的结构形式:在围堰的预进占段采用摆喷注浆,孔距为13m;在围堰的龙口段采用摆喷注浆与旋喷注浆相结合,孔距12m。注浆孔采用旋转液压钻机造孔,要求孔位偏离小于10cm,孔斜率小于10%,注浆按施工单元分序进行。防渗板墙的施工质量经采用电法探测等方法检查。

The construction scheme of grouting with high pressure and building cutoff wall were selected according to cofferdam structure and its geological conditions in order to insure its antiseepage ability. The cutoff wall is laid along the axis of the cofferdam;different grouting processes were adopted in its different sections.Its construction quality is accord with the demands of design after checked.