Construction method for in-situ extension of super-large section tunnel in collapse section

• Main Authors: ZHANG JUNRU, GONG YANFENG, DU JIANGSHAN, ZHANG XINSHENG, WANG SHENGTAO, HUANG YONGHU, ZHU PINGHUA, CHEN WENYIN, SUN WENHAO, HOU ZHIQIANG, CHEN PENGTAO, LI DINGYOU, LI SHUPENG, FENG JIMENG
• Format: Patent
• Language: Chinese; English
• Published: 12.07.2024
• Subjects: EARTH DRILLING; FIXED CONSTRUCTIONS; GALLERIES; LARGE UNDERGROUND CHAMBERS; MINING; SHAFTS; TUNNELS

The invention provides a collapse section in-situ extension super-large section tunnel construction method which comprises the steps that an existing tunnel penetrating through a collapse section is detected to determine the characteristics of the collapse section, and the collapse section is reinforced based on the characteristics of the collapse section; a free face of the tunnel to be extended is excavated based on the existing tunnel, and the free face is divided into a first area and a second area; the tunnel to be extended is backfilled to the joint of the second area and the first area, and backfilled soil is compacted; and after compaction is completed, a lining of the existing tunnel is dismantled, and expanding excavation is sequentially conducted on the position, relative to the first area, of the to-be-expanded tunnel and the position, relative to the second area, of the to-be-expanded tunnel. By means of the method and device, the surrounding rock pressure can be balanced to a certain degree, the