Moment response of short rectangular piers in sand

The moment response of rectangular piers was investigated numerically using a three-dimensional, non-linear finite element program, and by centrifuge modelling. In general numerical modelling behaviour matches observation well. Moment capacity increases almost linearly with pier length and simple expressions are derived. Dimensionless moment factors increase with soil packing but decrease significantly with pier length for aspect ratios less than 1.33. Prototype moment limits derived from the numerical and centrifuge studies compare reasonably well with predictions from the UIC/ORE and Broms design methods. © 2003 Elsevier Ltd. All rights reserved

Uplift response of strip anchors in cohesionless soil

Physical and computational studies investigating the uplift response of 1 m wide strip anchors in sand show that maximum resistances increase with anchor embedment ratio and sand packing. Agreement between uplift capacities from centrifuge and finite element modelling using PLAXIS, based on 0.2 m computed maximum displacements, is excellent for anchors up to embedment ratios of 6. Some divergence occurs for deeper anchors. Pre-peak response is reasonably well reproduced using the Hardening Soil Model available in PLAXIS, although the characteristic post-peak softening in some physical model tests requires a more sophisticated soil model. PLAXIS also produces breakout factors which compare reasonably well with established limit state and finite element based theories. © 2006 Elsevier Ltd. and Civil-Comp Ltd

Three-dimensional finite element studies of the moment-carrying capacity of short pier foundations in cohesionless soil

This study is concerned with the moment-carrying capacity of short pier foundations in loose and dense cohesionless soil. The results of non-linear three-dimensional finite element analyses are compared with data from centrifuge tests modelling the behaviour of 1 m diameter prototype piers. The numerical predictions are shown to be very sensitive to the value of coefficient of earth pressure at rest, K0, and most closely match observations when K0 = 0.6 is assumed. The results of parametric studies of square prototype piers in loose and dense cohesionless soils are then presented. Empirical equations are derived between moment-carrying capacity and pier geometry, for limiting pier rotations of 1°and 2°, and very close fits are demonstrated between the values given by these equations and the original computed values.University of Liverpool NATO-B2The research presented in this paper was performed at the University of Liverpool while the first writer was supported by a “TUBITAK, NATO-B2” Scholarship awarded by the Technical Research Council of Turkey