Core Viewpoint - The successful completion of the Gongdefang Tunnel marks a significant milestone for the Xichang to Ningnan Expressway project, which aims to be operational by 2027, enhancing regional connectivity and economic development [1][6]. Group 1: Project Overview - The Gongdefang Tunnel connects villages in Liangshan Yi Autonomous Prefecture, with the left line measuring 3,168 meters and the right line 3,205 meters, featuring a maximum burial depth of approximately 345 meters [3]. - The tunnel is classified as a long micro-gas tunnel, constructed using a dual-end excavation method, and traverses active fault zones, presenting high construction difficulty and safety risks [3][4]. Group 2: Construction Techniques and Innovations - The project team has implemented advanced geological prediction and monitoring, along with strict management protocols to ensure safety and quality during construction [3]. - Innovative construction technologies, including intelligent tunneling equipment and digital monitoring systems, have been adopted to enhance efficiency and safety [4]. Group 3: Environmental Considerations - The project has developed a "clean and dirty water diversion" drainage technology to address challenges related to wastewater discharge, reducing labor and operational costs while protecting the surrounding ecological environment [4]. Group 4: Economic and Social Impact - Upon completion, the expressway will reduce travel time from Xichang to Ningnan from 2.5 hours to 1 hour, ending the historical lack of expressway access for Puge County and contributing to regional economic development and tourism [6]. - The project is a key component of the S71 expressway, enhancing the transportation network and solidifying Liangshan's role as a transportation hub in southern Sichuan [6].