浅谈低净空地下连续墙施工关键技术

Brief Discussion on Key Construction Technology of Low-clearance Diaphragm Wall

低净空环境是基坑围护结构施工过程中不可避免的难点之一,该施工问题在高架桥、高压线等基础设施下较为常见。根据南昌丹霞路综合管廊项目对高压线下低净空地下连续墙围护结构施工进行关键技术研究。结果表明,分节吊装过程中,钢筋笼分节组合断面宜设置多个断面;采用抓-铣结合工艺能有效缩短工期;工字钢接头内侧需进行二次处理,避免钢筋笼无法有效下放。

Low-clearance environment is one of the inevitable difficulties in the construction of foundation pit enclosure structure. This construction problem is common in the viaduct, high-voltage line and other infrastructure. According to Nanchang Danxia Road Utility Tunnel Project, the key technology in the construction of low-clearance diaphragm wall enclosure structure under the high-voltage line is studied.The results show that the segmental section of reinforcement cage should be equipped with the multiple sections in the process of segmental hoisting. The grab-milling combined process can effectively shorten the construction period. The inner side of the I-steel joint needs secondary treatment to avoid the failure of the reinforcement cage to lower effectively.