Nonlinear Pushover Analysis of Bridge Columns Supported on Full-Moment Connection CISS Piles on Clays

Abstract

This paper summarizes results from a static pushover analysis on the inelastic response of bridge columns supported on pile groups and consisting of full moment connection cast-in-place steel shell piles. The analytical models considered the nonlinear actions that develop in the column, the supporting piles and the soil. Parametric studies were then carried out under different sets of column height to diameter or aspect ratios and soil–structure interaction, and included variations in: (a) nonlinear soil–structure horizontal interaction and (b) nonlinear soil–structure vertical interaction. Parametric studies confirmed that variations in the horizontal and vertical soil stiffness can affect the pile cap lateral deflection and rotation, respectively. As importantly, results from this analysis indicate that for columns with aspect ratios lower than six, the contribution of soil–structure interaction is significant; however, for columns with higher aspect ratios and for stiffer soils, the effects of soil–structure interaction are almost negligible regarding the lateral response of the system. Detailed results from this study are presented and discussed in this paper.