In high density cities such as Singapore and Hong Kong, infrastructure development on soft grounds is not an uncommon engineering issue. Accurate settlement prediction is important in large scale of infrastructure design and construction. By comparing the use of numerical analysis and traditional empirical methods. The former provides an efficient approach to model the soil-structure interactions for geotechnical engineering practitioners.

The objective of this MPhil thesis study is to investigate the methodology of numerical settlement analysis in pile raft tunnel modelling by calibration with empirical methods. A numerical model for a pile-raft tunnel is built and verified by 1-D consolidation theory. The calibrated numerical model simulates the soil-structure interactions between th...[ Read more ]

In high density cities such as Singapore and Hong Kong, infrastructure development on soft grounds is not an uncommon engineering issue. Accurate settlement prediction is important in large scale of infrastructure design and construction. By comparing the use of numerical analysis and traditional empirical methods. The former provides an efficient approach to model the soil-structure interactions for geotechnical engineering practitioners.

The objective of this MPhil thesis study is to investigate the methodology of numerical settlement analysis in pile raft tunnel modelling by calibration with empirical methods. A numerical model for a pile-raft tunnel is built and verified by 1-D consolidation theory. The calibrated numerical model simulates the soil-structure interactions between the soft ground and the tunnel structure. These models are built by assuming a raft tunnel founded on soft grounds with design requirements of 1:300 in differential settlement gradient and 500 mm in post-construction settlement during 50 years of design life.

In this study, the traditional tunnel settlement analysis is reviewed based on discrete 1-D consolidation theory. In connection to the empirical analysis, the results are compared with those from the numerical tunnel modelling. The behaviour and performance of the raft tunnel such as settlement and differential settlement are compared, while the structural behaviour of the tunnel under the analyses are also investigated.

This thesis formed a solid foundation to facilitate the use of numerical analysis in the industry in order to better simulate the soil-structure interactions under complicated geological profile through comparison studies using both the traditional industrial approach and numerical modelling.