Based on the construction of Nanjing Weisan Road Yangtze River Tunnel, this book comprehensively introduces the new technology of large-diameter shield tunnel construction crossing circular air shafts. It focuses on four aspects: the construction technology of super-deep circular air shaft foundation pit retaining structure in the sensitive environment near the river, underwater excavation and underwater massive concrete sealing bottom construction technology, adaptive improvement of TBM and construction technology of crossing air shaft, and control technology of super-deep foundation pit stability during the process of conversion. This book combines theory with practice, and can provide reference for shield engineering construction. It can also be used as a reference for engineering and technical personnel, researchers, teachers and students in related majors in colleges who are engaged in shield tunnel engineering.