Optimized Design for Soil-Pile Interaction and Abutment Size of Integral Abutment Bridges

摘要

In the last few years, the integral abutment bridge (IAB) concept has become quite common. It is,rnincidentally, not a newly developed concept, its formulation dating back at least to the 1930s, inrnorder to deal with long-term structural problems frequently occurring with conventional bridgerndesign. At present, the IAB concept is generating considerable interest among bridge engineersrnbecause of the enormous benefits due to elimination of expansive joints and reduced installationrnand maintenance costs. The superstructure of integral abutment bridges is made continuous throughrna composite cast-in-place concrete deck slab over prestressed concrete or steel girders andrncontinuity diaphragms, and the system constituted by the sub- and the super-structure acts as arnsingle structural unit.rnA usual and important problem in the design of IABs is how to deal with the soil-structurerninteraction behind the abutments or next to the foundation piles: this can be considered as arnfundamental aspect for the thorough understanding of this type of structures, which requiresrniterative and nonlinear analysis. In this paper, a 2D simplified finite-element model of a real 400rnmeters long IAB, built in the Province of Verona-Italy, will be implemented and used to performrnnon linear analysis on the bridge. Then, based on the results obtained from a parametric study onrnthe IAB, the analysis of effects of soil-pile interaction and the abutment size will be carried out tornfind out the relative key parameters in IABs design.