On May 3, after 560 days of arduous efforts, both tubes of the Tianfuwan Tunnel on the Lixian Expressway, constructed by CCCC Second Harbor Engineering Co., Ltd., were fully holed through, marking a major breakthrough in the construction of the Lixian Expressway.

The Lixian Expressway is an important component of the "Vertical Line 9" in the "Nine Vertical, Five Horizontal and Four Ring" expressway network planned by Hubei Province. It has a total length of about 84.6 km and is built to the standard of an 80 km/h, two-way four-lane expressway. Section 4, which is under the responsibility of CCCC Second Harbor Engineering Co., Ltd., is about 16 km long, with a bridge-to-tunnel ratio of 81.3%.

The Tianfuwan Tunnel is located in Lizixi Village, Xiaocun Township and Shabaoxi Village, Tangya Town. Its left tube is 2,515 meters long with a maximum burial depth of 386.64 meters; its right tube is 2,635 meters long with a maximum burial depth of 388.99 meters. The tunnel construction area features tectonic erosion-denudation middle and low mountain landforms, with Grade IV and V surrounding rock accounting for more than 88%, and the geological conditions are complex and variable. The tube holed through this time is the right tube of the Tianfuwan Tunnel; the left tube was successfully holed through on April 8.

The Tianfuwan Tunnel presented many unfavorable factors, including complex geological structures, poor road transport conditions and high safety risks. The project department adopted technical safeguard measures such as advanced geological drilling, geological sketching of the tunnel face, real-time data monitoring and dynamic adjustment of support parameters, ensuring the smooth progress of the tunnel. Through measures such as organizing experts to review safety technical plans, inviting experts to the site for technical guidance, and implementing the leadership responsibility system and the leadership shift supervision system for key processes, strong guarantees were provided for the progress, safety and quality management of tunnel construction. The successful holing-through of the Tianfuwan Tunnel laid the road transport foundation for the T-beam erection of the Mahe Bridge in this project.

The Lixian Expressway project is a major transport artery opening up the core area of the Wuling Mountains in Hubei, Hunan, Chongqing and Guizhou. Once completed, the travel time from Lichuan to Xianfeng will be shortened from 2.5 hours to 1 hour, effectively solving the rapid travel problem for nearly 400,000 people in Lichuan and Xianfeng counties. It is of great significance for driving the development and utilization of clean energy, eco-tourism and other resources in the Wuling Mountain area, and for helping Enshi Prefecture consolidate its poverty alleviation achievements and promote rural revitalization.