On April 11, accompanied by a loud blast, the left tube of the Dawangdong No. 2 Tunnel on the Yangchun–Xinyi (Guangdong–Guangxi border) Expressway, invested by China Railway and China Railway Southern Investment and constructed by China Railway Sixth Group, was successfully holed through, marking major progress in the construction of the Yangxin Expressway and laying a solid foundation for the opening of the entire line on schedule.

Tunnel holing-through site

　　It is understood that once completed, the Yangxin Expressway will form a fast corridor from central western Guangdong to the central and southern areas of the Guangdong–Hong Kong–Macao Greater Bay Area, greatly shortening road travel time between Yangchun and Xinyi, significantly improving local road freight capacity and travel conditions for residents along the route, and playing an important role in improving Guangdong Province's expressway network and implementing strategic deployments such as the Guangdong Provincial Party Committee and Provincial Government's "rural revitalization strategy."

　　According to reports, the Dawangdong No. 2 Tunnel is located in Dapo Town, Gaozhou City, Guangdong Province. Its left tube is 712 meters long with a maximum burial depth of 91 meters, and its right tube is 688 meters long with a maximum burial depth of 91.5 meters. It is a controlling project of the scheme, and its holing-through lays the foundation for the subsequent girder erection construction of the Panshuitan Bridge and the Bantangling Bridge.

　　A relevant person in charge of the contractor stated that the tunnel passes through weak, large-deformation sections, with Grade IV and V surrounding rock accounting for more than 60 percent, making construction difficult and high-risk. The project department ensured the safety of the Dawangdong No. 2 Tunnel construction by strengthening design and strictly controlling construction.

　　During construction, the project team adopted the concept of dynamic design and construction. Through advanced geological forecasting and monitoring and measurement work, it dynamically adjusted parameters such as support in a timely manner, thereby improving the safety of tunnel construction.