Creating space underground

In all major cities, creation of underground spaces to accommodate transportation, communication and utility networks, and completes for handling, processing and storage of many Kinds of materials, is now a high priority in order to protect the living environment at ground level. This paper describes various techniques for creating underground space, including cut-and-cover methods and the New Austrian Tunneling Method, with particular reference to mass transit railway and urban expressway projects undertaken in. Hong Kong, Bangkok, Singapore and London. Innovative design, techniques for underground spaces and the interrelationship between construction method and structural envelope design are discussed.