Discussion: Design of piled bridge abutments on soft clay for loading from lateral soil movements

Abstract

Piles supporting bridge abutments on soft clay may be loaded laterally from horizontal soil movements generated by the approach embankment. The design of piles loaded by lateral soil movements is problematic in that existing design approaches are generally inconsistent or show poor correlation with available data. New empirical design charts are presented to allow an assessment of maximum pile bending moment and pile head deflection based on the relative soil-pile stiffness and current loading level. A new analytical approach is also developed on the basis of a simple deformation mechanism. The method accounts for the main features of the problem through an approximate representation of the embankment-soil-pile interaction, and is shown to compare favourably with centrifuge model test data. Recommendations for the design of pile groups for loading from lateral soil movements are also given.