Core Viewpoint - The completion of the Yong'an Long Tunnel marks a significant milestone in the construction of the "first red-themed expressway in the country," the Zhan-Guang Expressway, which is expected to enhance transportation and tourism in the region [1][6]. Group 1: Project Overview - The Yong'an Long Tunnel, located in Tongjiang County, is the longest tunnel of the Zhan-Guang Expressway, with a left tunnel length of 6,862 meters and a right tunnel length of 6,825 meters, reaching a maximum depth of 580 meters [3]. - The Zhan-Guang Expressway has a total length of 250.825 kilometers and a total investment of 48.9089 billion yuan, designed for a speed of 100 km/h [6]. Group 2: Construction Progress - Currently, the excavation, filling, tunnel, and pile foundation construction of the Zhan-Guang Expressway from the Sichuan-Shaanxi border to Wangping has exceeded 70%, with the construction of piers and caps progressing past the halfway mark [4]. - The project team has implemented a dual guarantee system of "risk prediction + precise control" to address complex geological conditions, utilizing advanced intelligent equipment for construction [3]. Group 3: Technological Innovations - The project has introduced advanced intelligent equipment, reducing the number of workers in single tunnel operations by 20% and shortening drilling and blasting operation time by 20%, while doubling the efficiency of arch installation [3]. - The use of smooth blasting technology and innovative lining techniques has achieved a lining qualification rate of over 99%, ensuring high-quality construction [3]. Group 4: Economic and Social Impact - Upon completion, the Zhan-Guang Expressway will connect several significant red tourism sites, forming a "3-hour red tourism circle" and improving travel conditions for local communities [6]. - The expressway is expected to inject new momentum into the revitalization and development of the old revolutionary areas in Sichuan and Shaanxi [6].

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].