Ground movements in shield tunnelling for MRT Orange Line in Bangkok

In urban areas, the increased demand for underground systems is being addressed, especially the construction of tunnels. Recently, the most current metro line of the MRT Orange Line (East Section) project in Bangkok, Thailand has been successfully constructed using Earth Pressure Balance shield machines. Several instrumentation and monitoring systems were utilized in this project to observe the characteristics of ground movements induced by tunnel construction along the alignment. This paper presents field data of ground surface settlement obtained during the construction along the tunnel alignment. Evaluation of ground responses to comprehensively back-analyse and determine typical values of settlement trough width parameter and volume loss ratio for the encountered soil conditions is presented. Particular attention is also given to the recommended values which can be implemented in engineering practice to preliminarily predict ground movements due to tunnelling and other relevant issues for future tunnelling projects in this region