This book focuses on some technical problems encountered in shield tunneling in hard¿soft uneven stratum and extremely soft stratum, based on the recent shield tunneling engineering practice, and summarizes the achievements of shield tunneling in view of the technical problems from an overall and objective perspective. There are 6 chapters in this book. Chapter 1 introduces the development trend of shield tunneling method, defines classification of various stratum where shield tunneling applies, and mainly analyses the selection of shield machines and the configuration of cutters. Chapters 2 to 5 elaborates the strata characteristics and construction difficulties under various stratum conditions, puts forward adaptive selection and design keys of shield in various stratum, and emphatically analyses and summarizes the stability control technologies of shield tunnel face and driving control technology by case studies. Chapter 6 introduces the shield chamber opening technologies under hyperbaric condition, emphatically presents the basic requirements and operational preparations for the shield chamber opening, and puts forward innovative ideas of operation procedures, control points of key procedures, and safety requirements of shield chamber opening under hyperbaric condition.