Recently, at the construction site of the Ankang-Lan'gao Expressway Lan'gao to Shaanxi-Chongqing Boundary project in Shaanxi, with a blast at the working face of the left tube of the Taohe Tunnel, the left tube of the Taohe Tunnel on the Anlan Expressway was successfully holed through, marking the successful achievement of the goal of holing through both tubes of the tunnel.

The Taohe Tunnel has a total length of 645 meters and is located on the street of Taohe Town. It is designed as a dual-carriageway with four lanes and a maximum buried depth of about 235 meters. The tunnel exit is located on a mountain slope with a relatively steep terrain gradient. The surrounding rock is mainly strongly weathered slate, which is prone to block falling and collapse under excavation disturbance. The exit construction is relatively difficult, affecting the stability of the portal slope and posing a relatively high safety risk. To ensure safe tunnel construction, the project builders stayed at their posts during the holiday period. Through advanced geological prediction methods such as ground-penetrating radar, they increased the frequency of monitoring and measurement, promptly analyzed the detection data, grasped the deformation patterns of the surrounding rock, assessed the deformation trends of the surrounding rock, and identified adverse geological locations in advance. During construction, the bench conversion method and double-layer small pipe grouting measures were adopted to safely exit the tunnel, ensuring orderly tunneling, controllable quality, and safe and efficient construction.

The Lan'gao to Shaanxi-Chongqing Boundary Expressway is an important component section of the Yinbai Line (G69) of the national expressway network, and is also a newly added longitudinal highway in the National Highway Network Plan. It is a key section for Ankang to break through the Bashan barrier southward and connect to the Chengdu-Chongqing Economic Zone. The implementation of this project is of great significance for carrying out the Western Development Strategy and jointly building high-quality Belt and Road cooperation, improving the national expressway network, improving regional traffic conditions, and promoting resource development and coordinated economic and social development along the route.

The Lan'gao to Shaanxi-Chongqing Boundary section of the Anlan Expressway is expected to be completed and opened to traffic in 2025. By then, the driving time from Ankang, Shaanxi to Kaizhou, Chongqing will be shortened from the current 9 hours to 2.5 hours, reducing travel time by 70%.