GROUND SUBSIDENCE AND BUILDING DISTRESS DUE TO CONSTRUCTION OF TWIN TUNNELS

Abstract

Tunnel construction, especially in soft ground conditions, invariable cause ground movements which have the potential to damage existing buildings and other structures. Conventional empirical and closed form solutions have major limitations when used in the prediction of ground movements affected by adjacent structures. Also, the idealization employed in a two dimensional plane strain problem cannot capture all the aspects of the complex three dimensional soil-structure-tunnel interaction. Also, the effects of tunnelling on adjacent piles cannot be studied by simulating it as a two dimensional problem. The effect of different kinds of building on surface profile has been studied. The objective of this thesis is to understand the mechanisms involved in the soil-structure-tunnel and pile-soil-tunnel interactions. Also the effect of grout pressure. face pressure and jack force on ground subsidence has been studied. The parameters involved in both the interactions were studied by referring the previously done research works and by conducting analysis in PLAXIS 3D. The use of three dimensional plastic soil models is pivotal in the study of soil-structure interaction. Also, studies were conducted on the possible ways to mitigate the damages caused as a result of tunnel excavations on adjacent structures