Seminar - Nagendran Loganathan - Effect of tunnelling adjacent to pile raft foundation system

Wednesday, September 15, 1999, 3 - 4 pm
Civil Engineering Lecture Room 3

Abstract

The construction of tunnels inevitably causes ground movements.
Current design practice to predict tunnelling-induced ground movements is
generally based on empirical methods that are subjected to some important
limitations. In the urban environment tunnelling-induce ground movements
present a risk of damage to adjacent buildings and structures. At present,
there are no proper methods to assess the tunnelling-induced behavior of
adjacent piles. In this study, design charts were established to estimate the
ground loss due to tunnel excavation and these ground loss values were
incorporated on to analytical solutions to predict the ground movements
around the tunnel in clays. In addition, numerical study was performed to
assess the tunelling-induced pile behaviour and design charts were
established by performing parametric study. Laboratory centrifuge tests
were carried out to check the applicability of the closed-form solutions and
the design charts established in this study. Results obtained from centrifuge
tests and field data from few case studies compared reasonably well with
the closed-form solutions and design charts presented in this study.