Behaviour of soldier piles and timber lagging support systems

Abstract

Strutted soldier-piled excavations are often analysed using two-dimensional finite element analyses with properties that are averaged over a certain span of the wall. In this thesis, the effects of a??smearinga?? the stiffness of the soldier piles and timber laggings into an equivalent uniform stiffness are examined, based on comparison between the results of 2D and 3D analyses. The results of 2D and 3D analyses on an idealized soldier piled excavation are compared.Some results of a comparative study on the effects of different constitutive models in simulating soldier-piled excavations in medium to stiff soils will be discussed. The field data from the excavation for the Serangoon station of the North-East Line contract 704 were used as reference in this comparative study. The models compared in this thesis include Mohr Coulomb, modified Cam-clay and hyperbolic Cam-clay. 2D and 3D analyses are conducted to examine the stress changes and wall deflection development during excavation and its final settlement profile.