A REVISIT TONICOLL HIGHWAY EXCAVATION IN SINGAPORE

This paper demonstrates the use of explicit finite difference program FLAC to numerically simulate staged braced excavation involving various stages of excavation and strutting. The short term undrained condition is considered in the analyses. A FISH script is developed, with automatic mesh generation capacity, to study the behavior of wall deformation and ground settlement during the stages of construction. The numerical model is developed using the case study of Nicoll Highway in Singapore. Both the geotechnical design and the causes of failure of the Nicoll Highway excavation are re-visited through extensive comparisons with existing published data. It is considered as a successful development with the main purpose in mind to develop a numerical model for the analysis of staged excavation in the construction of underground basements. The success of the development is to be used in assisting other design projects in the future.