镇广高速公路永安特长隧道全幅贯通

Core Viewpoint - The completion of the Yong'an Long Tunnel marks a significant milestone in the construction of the Zhan-Guan Expressway, which is a key transportation route connecting Shanxi Province and Sichuan Province [1][3]. Group 1: Project Overview - The Zhan-Guan Expressway, with a total length of 250.825 kilometers, is designed with a dual four-lane standard and a speed limit of 100 km/h [3]. - The expressway consists of three segments: the section from the Sichuan-Shaanxi border to Wangping, Wangping to Tongjiang, and Tongjiang to Guang'an, with the Wangping to Tongjiang section already completed [3]. Group 2: Engineering Challenges and Innovations - The Yong'an Long Tunnel, the longest tunnel on the Zhan-Guan Expressway, has a left tunnel length of 6,862 meters and a right tunnel length of 6,825 meters, with a maximum burial depth of 580 meters [3]. - The construction team utilized advanced intelligent geological detection equipment to identify potential hazards and implemented "mechanization replacing manpower and intelligence reducing manpower," resulting in a 20% reduction in personnel for single tunnel operations and a 20% reduction in drilling and blasting work hours [3]. - The use of smooth blasting technology minimized disturbances to surrounding rock, thereby reducing safety risks during construction [3]. Group 3: Current Progress and Future Plans - As of now, the construction progress of the Zhan-Guan Expressway from the Sichuan-Shaanxi border to Wangping has exceeded 70%, with more than half of the pier and cap beam construction completed [4]. - The Tongjiang to Guang'an section is expected to be completed and open to traffic by the end of 2025, covering a distance of 100 kilometers [4].