Analysis and Testing of Piles for Ship Impact Defenses

Abstract

This paper deals with analyses and reduced scale tests carried out to validate the design of flexible protection structures for bridge piers against ship impact. The protection system analyzed is part of the fixed link currently under construction across the Parana River between the cities of Rosario and Victoria in Argentina, and it will protect a cable-stayed bridge and parts of the approach viaduct against impact of aberrant vessels with sizes up to 100,000 DWT. The protection system was designed on the basis of dissipated energy and consists of groups of steel-encased large diameter concrete piles connected at the top by a reinforced concrete platform. The impact energy is to be absorbed by large horizontal displacements of the pile caps that involve large deformations of the surrounding soil and geometrically and material nonlinear response of the pile shafts themselves. The paper focuses on modeling the nonlinear characteristics of the response of the structure, and on its assessment by means of 1:15 scale model tests performed in both the laboratory and in the field to account for the displacements and deformations undergone by the pile shafts.