Chinanews.com, Lincang, August 1 (Wang Peng, Wang Yixiang, Yang Hua) After 1552 days of hard work by the builders, the Baishitou tunnel on the Dali-Lincang railway in Yunnan was completed, laying the foundation for the completion of the entire line on schedule.
The Baishitou Tunnel is located in Yunxian County, Lincang City, Yunnan Province, with a total length of 9.375 kilometers. The tunnel passes through the shallow buried section of the Dawanzi River with a minimum depth of only 8 meters. The surrounding rocks are mainly soft rocks such as sericite and carbonaceous schist. Mainly, affected by multi-period earthquakes, the rock mass is broken and low in strength, making the construction extremely difficult.
The picture shows the builders digging in the tunnel. Photo courtesy of China Railway Kunming Bureau Group
The Baishitou Tunnel has construction difficulties such as high temperature, collapse, faults, and mud outburst, especially the large deformation of soft rock, with a cumulative deformation of 1.05 meters. Through a series of measures such as shortening the excavation footage, strictly controlling the construction of the first branch and leading small pipe, and the initial support grouting reinforcement, the China Railway 17th Bureau has realized the rapid construction of the soft rock tunnel with short footage, strong support and early closure, ensuring the tunnel Go through on schedule.
In view of the complex geological conditions of the tunnel, China Railway Kunming Bureau Group Co., Ltd., in collaboration with the participating units, set the target task of "100 days to win the Dalin Railway". Through measures such as optimizing design parameters and adjusting construction methods, they concluded A set of practical construction plan, the construction progress can reach up to 90 meters per month.
The picture shows the builders digging in the tunnel. Photo courtesy of China Railway Kunming Bureau Group
"After the Baishitou Tunnel was completed as scheduled, the track laying channel from Yunxian County to the Baishitou Tunnel section was opened, creating favorable conditions for the next step of manual track laying." China Railway Kunming Bureau Group Yunnan West Railway Construction Headquarters Dalin Section Headquarters Commander Chen Yingwu said.
The Dali-Lincang Railway, which is under construction, is an important passage in Yunnan’s “eight out of the province and five out of the country” railway network. After nearly five years of intensive construction, the entire line has now entered the sprint stage. The Dali Railway departs from Dali Station, passes through Weishan County and Nanjian County in Dali Prefecture, and crosses the Lancang River via Yun County to Linxiang District of Lincang City. The total length is 202 kilometers and the bridge-tunnel ratio is 87%. Grade single-track electrified railway. After it is completed and opened to traffic, the history of no railway in Lincang, Yunnan will end. (Finish)