Target parameter Selection Method in Modal Pushover Analysis of Pile Foundation System for Deep Water Bridges

Abstract:

A theory of best control parameters (BCP) is developed based on Chopra’s approach to tackle the problem. Theoretical derivation and selection principle of BCP are also presented. A modal pushover analysis(MPA) of a pile foundation from Shanghai Changjiang Bridge is then conducted by using the developed BCP approach. First mode pushover analysis (Po 1) and nonlinear time history analysis (THA) of the pile foundation system are also conducted as the reference. The following conclusions are drawn through a comparative study: the BCP selection method efficiently resolves the reversal phenomenon in MPA of the pile foundation system; the displacement demands estimated by MPA with the selected BCP are closer to the results of THA, and much better than those provided by Po 1.

Key words:pile foundation system for deep water bridges; reversal phenomenon; best control parameters(BCP); modal pushover analysis(MPA); lateral force pattern