Vast knowledge has been developed in the area of tunnelling in weak rocks over the years, and this book bridges an important gap by bringing all the information together for the benefit of the tunnelling Industry. In particular, tunnelling in poor conditions is a huge challenge for engineers and designers, and this book tackles all typical problems headon.Topics covered include classification approach, design approaches for site-specific grounds, a new invention on shielded tunnel boring machine, case histories, tunnel mechanics, risk engineering and management culture.