Design for a large underground space

摘要

Large underground spaces are required when constructing multifunctional buildings. These constitute one of the major engineering projects for the World Expo 2010 in Shanghai, China. Restrictions caused by a building's function, and requirements for arranging municipal pipelines, mean that options for structural systems are limited. This paper presents a scheme design for a large underground space. To achieve a spacious underground passage and to resist the heavy load of the soil that holds pipelines, major structural systems are taken into consideration. Performance criteria for a scheme design involve safety, serviceability and economics. Subsequently, comparisons of a conventional reinforced concrete (RC) system, a prestressed RC system, and a steel-concrete composite (SCC) system are made with regard to these criteria. It is found that a conventional RC structure cannot provide adequate resistance to heavy load at a large column span. Correspondingly, prestressed RC slabs can replace conventional RC structures with the required structural capacity, but suffer drawbacks because construction space is confined. A composite system is desirable for an underground space with a large span and heavy load. Specifically, it has a convenient construction procedure and high economic efficiency which takes advantage of industrial manufacturing of steel members and reduction of concrete formwork.