Group 1 - The successful completion of the "Tianjin City No. 1" shield tunneling machine marks the breakthrough of the Tianjin-Weifang High-speed Railway's key control project, the Tianjin-Du Haihe Tunnel [1] - The Tianjin-Weifang High-speed Railway has a total length of 348.9 kilometers and a design speed of 350 kilometers per hour, connecting Tianjin Binhai Station to Weifang North Station on the Jiqing High-speed Railway [1] - The Tianjin-Du Haihe Tunnel, at approximately 6.5 kilometers long, is the only tunnel along the Tianjin-Weifang High-speed Railway and the first high-speed railway tunnel over the Haihe River [1] Group 2 - The project is part of China's "Eight Vertical and Eight Horizontal" high-speed rail network, specifically the Beijing-Shanghai corridor and the coastal corridor, enhancing the transportation network in the Bohai Rim region [2] - The completion of the Tianjin-Weifang High-speed Railway will facilitate travel for local residents and support the coordinated development of the Beijing-Tianjin-Hebei region and the Shandong Peninsula urban agglomeration [2]