Xinhua News Agency, Beijing, May 7 (Reporter Ye Haoming) The reporter learned from the Ministry of Transport on the 7th that after 1,155 days of construction, the longest spiral tunnel in China - Laoyingpan Tunnel No. 1 of Xizhao Expressway was successfully completed on the same day. So far, the three tunnels of the Laoyingpan tunnel group have been completed, laying the foundation for the completion of the Xizhao Expressway.

According to Han Yongjun, project manager of Xizhao Expressway of China Railway Second Bureau Sixth Engineering Co., Ltd., the Laoyingpan tunnel group is located in the alpine valley area of Jinyang County, Liangshan Prefecture, Sichuan, with a straight-line distance of only 1.6 kilometers from the entrance and exit of the tunnel group, with a height difference of 213 meters. The Lao Ying Pun Tunnel No. 1 is one of the control works of the Xizhao Expressway, with a total length of about 5.1 kilometers. Previously, Tunnel 2, which is about 1.05 kilometers long, and Tunnel 3, which is about 1.24 kilometers long, have been broken through on April 7, 2024 and December 30, 2023, respectively.

During the construction process, China Railway Xizhao Expressway Co., Ltd. and China Railway Second Bureau Xizhao Expressway Project Department set up a scientific research team to overcome the problems of high geostress, large buried depth, soft rock construction, serious convergence and settlement of initial support, tunnel karst, fault, and large deformation of soft rock to ensure the smooth construction of Xizhao Expressway.

Xizhao Expressway is an important component of the Duxiang Expressway planned in the national highway network, invested and constructed by China Railway and China Railway Urban Investment Group, with a total length of 184.8 kilometers and a total investment of 31.417 billion yuan, and the whole line adopts the standard construction of four-lane expressway, with a design speed of 80 kilometers per hour. As a highway connecting Zhaotong City in Yunnan Province and Xichang City in Sichuan Province, Xizhao Expressway is of great significance for accelerating local social and economic development.