Point of Fixity Analysis of Laterally Loaded Bridge Bents

Abstract

Research work in this thesis deals with the effects of lateral loads in the longitudinal direction on a substructure's point of fixity. Full scale tests were performed to model and test a section of a bridge where the superstructure is connected to the substructure through elastomeric bearing pads. The connection rotational stiffness between the super and substructure was measured as an effect of applying a lateral load to the foundation element and creating a moment at the connection joint. A circular concrete pile, square concrete pile, and steel H-pile were tested in connection with both type V and type VI elastomeric bearing pads. The response of these full scale tests were then modeled in FB-MultiPier as tested and as an equivalent single foundation element. The model response was then compared to the measured results. Through the use of FB-MultiPier, three existing North Carolina bridges' foundation elements were analyzed to determine an effective range of partial head fixity and its compounding effects on the development of a foundation element's depth to fixity.