双层套管同心跟管成孔工艺在复杂地层的应用

Application of Technology for Hole Making by Concentric Casing with Double-wall Tube

猴子岩水电站格宗移民场平工程子格里料场开挖时,其后边坡地质结构复杂,基岩为强风化强卸荷带,预应力锚索施工成孔难度大,常规单层套管偏心跟管、同心跟管和固壁灌浆成孔方式不能满足成孔要求,进度慢、成本高。采取双层套管同心跟管工艺有效地解决了在复杂地层预应力锚索成孔难题。

When the Zigeli quarry for Gezong population resettlement leveling, Houziyan Hydropower Project, is excavated, it is difficult to make the holes for the prestressed anchor cables as the geological structure of its real slope is complicated and the bedrock is of the strongly weathered unloading zone. The conventional hole making methods such as the eccentric casing with sing/e-wall tube, concentric casing with single-wall tube and wall protected through grouting cannot have holes be made, and the construction speed is slow and the construction cost is high. Application of technology of the concentric casing with the double-wall tube effectively handles the difficulty in hole making for the prestressed anchor cables in the complicated stratrum.