Successful tunneling of the first large-diameter rock tunnel boring machine made in China

On August 22nd, China's first large-diameter open TBM “Changchun” roadheader successfully penetrated the second tender section of Jilin Songlin Project in Jilin City. During the excavation period, the average footage of the “Changchun” construction was 661.59 meters per month, which refreshed the new open TBM construction record in the country and created the most of the TBM class cross-section construction. The construction level reached the international lead, breaking the long-term monopoly of similar foreign technologies.

The “Changchun” is the result of the project “Key Technology Research and Application of Large-diameter Hard Rock Tunnel Excavation Equipment (TBM)”, a key project of the former National 863 Plan. The China Railway Construction Heavy Industry Group and the China Railway Construction 18th Bureau Group united with Zhejiang University. , Tianjin University, Central South University and other research institutions jointly research and development.

The “Key Technology Research and Application of Large-diameter Hard Rock Tunnel Excavation Equipment (TBM)” project was applied for by the State in 2011. Afterwards, we carried out technical research on complete machine design technology, cutter cutting tools, power drive and propulsion, etc.; and combined several different engineering geology features to carry out technological research, and successfully developed the first 8-meter-wide large-diameter open type in China in 2014. TBM prototype.

The second tender section of the Songsong project of Jilin Province has a total length of 22.6 kilometers, a minimum excavation diameter of 7.9 meters, a maximum depth of 750 meters, and a shallowest depth of 34 meters. The main rock formations are tuff and granite, and granite accounts for more than 50%. The maximum rock compressive strength exceeds 200 MPa, with more than 20 fracture zones.

In view of the geological features and technical difficulties of Jilin Songsong Project, Tiejian Heavy Industry jointly with China Railway No. 18 Bureau conquered the key technology of rapid tunnelling surrounding rock tunneling and TBM engineering application. Jointly Zhejiang University, Tianjin University and Central South University broke through the large-diameter TBM. High-efficiency rock breaking and other core technologies have been used to tailor-make large-diameter TBMs that are highly adaptable to the project and began to be excavated on March 18, 2015. (Yangyang)