Breakthrough site of the Huashengba Tunnel

On the morning of May 18, amid the roar of machinery, the left tube of the Huashengba Tunnel constructed by Sichuan Jiaojian Dehui was successfully holed through. The tunnel is the first on the entire Dehui (Dechang-Huili) Expressway to achieve breakthrough.

According to reports, the Dehui Expressway is 78.418 kilometers long and connects to the G5 Beijing-Kunming Expressway. It is the first expressway to begin construction in Huili County, Liangshan Prefecture, Sichuan Province. The holed-through left tube of the Huashengba Tunnel is 478 meters long, located in the ZK4+760-ZK5+238 section of the Dehui Expressway, and was constructed by the Sichuan Jiaojian Dehui TJ1-1 Project Management Department. The tunnel passes through quartz phyllite-metamorphic sandstone and quartzite-Xigeda Formation mudstone, with a maximum burial depth of 121.4 meters and a minimum cover layer of 8 meters. The design includes 295 meters of Class V surrounding rock, accounting for 61.72% of the total length, and 183 meters of Class IV surrounding rock, accounting for 38.28% of the total length. The complex geological conditions presented major challenges and high difficulty for construction quality and safety. Based on actual conditions, the Sichuan Jiaojian Dehui Expressway TJ1-1 Project Department continuously optimized the construction plan and construction scheme, reasonably reversed the construction schedule, closely followed the goals, and controlled the process well, becoming the first to complete the construction task of holing through the left tube of the Huashengba Tunnel.

The main line of the Dehui Expressway adopts a two-way four-lane design with a design speed of 80 kilometers per hour. The project officially started construction in June 2020 and is expected to be completed in June 2023. Once completed, the drive from Dechang to Huili will be shortened from the current two and a half hours to less than one hour.