<div id="readability-page-1"><div><p>China Railway Construction Corporation (CRCC) is advancing multiple undersea tunnel projects across the Bohai, Yellow, East, and South Seas, deploying domestically developed technologies to tackle complex geologic and engineering challenges. The projects aim to enhance regional connectivity along China's extensive coastline. Off the coast of Ningbo, in the East China Sea, the Yongzhou Railway's Jintang undersea tunnel is being excavated to a maximum depth of approximately 78 meters.</p><p>CRCC's engineers are using China's first integrated shield tunneling system with pressurized face operations, designed to manage high water pressure and allow safe, remote-controlled maintenance and cutter replacement. The system addresses critical technical gaps in China's construction of ultra-long and ultra-deep undersea tunnels. In the north, the Qingdao Jiaozhou Bay Second Tunnel, spanning 17.48 kilometers, is under construction using a combination of shield tunneling and conventional mining methods.</p><p>The approach enables safe passage through alternative hard rock and fractured zones. Meanwhile, in the south, the Shenzhen-Jiangmen Deep River undersea tunnel is advancing at depths reaching 116 meters, positioning it among the world's deepest high-speed rail tunnels beneath the sea. The Bohai region's Jinpu Sea River Tunnel, part of the Jinan-Qingdao high-speed line, has already been completed.</p><p>The project overcome highly corrosive saline soil and complex river-sea intersection zones through specialized anti-corrosion measures and precise engineering controls, ensuring the long-term stability of the massive shield tunneling equipment. From equipment manufacturing to smart construction, CRCC has established a complete technical system covering survey and design, construction management, core components, and digital operations. With multiple cross-sea tunnel projects progressing steadily, transportation connectivity along China's coastal regions and the level of regional integration are expected to improve further.</p></div></div>

华夏中证基建ETF

大成中证工程机械ETF

中国铁建

广发中证工程机械ETF

<p>中国铁建（CRCC）正在利用自主研发的技术推进各海域的海底隧道项目。主要项目包括深达 78 米的永州铁路金塘隧道、长 17.48 公里的青岛胶州湾第二隧道，以及深达 116 米的深圳 - 江门深河隧道。中国铁建采用一体化盾构隧道系统来应对高水压，确保安全作业。这些项目旨在增强中国沿海地区的连通性，改善交通一体化</p>

中国铁建利用自主研发技术推进海底隧道项目