Artificial Ground Freezing (AGF) is, nowadays, widely used in tunnelling for temporarily sealing rocks and soils, especially sandy soils with high water content for metro tunnel construction in large cities. This paper introduces the design and construction of cross passages for the Yangtze River Tunnel in Wuhan Metro Line-2. It is also the first metro tunnel across the Yangtze River. Among the five cross passages of this tunnel, #3 is the deepest below river bed in China, at 38.6m below the average water level of Yangtze River. The design parameters for the AGF construction are presented, and the performance of this construction technique is evaluated through measurements from the construction monitoring system. Several key issues in the AGF application are discussed and relevant precautions are proposed for the engineer's reference. Risk assessment and control functioned by an IoT (Internet of Things) based safety warning system was applied in this project. This case history provides a significant reference for another huge rail-road Yangtze River Tunnel with diameter of 15.76m in Wuhan Metro Line7, which is going to be constructed soon.
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