Core Viewpoint - The successful completion of the left tunnel of the Gou Tian section of Qingdao Metro Line 15 marks a significant milestone in the project, transitioning into the auxiliary engineering construction phase [1][3]. Group 1: Project Overview - The Gou Tian section has a total length of 778.58 meters and is characterized by challenging geological conditions, including weathered and water-rich volcanic rock strata [3]. - The construction area is located near high-density residential zones and involves complex risks, including the need to tunnel beneath existing infrastructure such as the Metro Line 1 [3]. Group 2: Construction Challenges and Solutions - The project team faced significant technical challenges, including maintaining the operational integrity of the existing Metro Line 1 while ensuring safety during the construction process [3]. - Innovative monitoring techniques, including the use of both manual and automated monitoring points, were implemented to collect data on the construction process and adjust tunneling parameters in real-time [3]. Group 3: Achievements and Future Plans - During the construction period, the team achieved over 10 standardized results and received multiple accolades, including recognition as a "3A Smart Construction Site" by Qingdao Municipal Public Engineering Quality Safety Supervision Station [5]. - The project team aims to maintain high-quality development and safety standards while focusing on meeting project milestones to contribute to the establishment of a world-class metro system in Qingdao [5].