BEHAVIOR OF PILE-SUPPORTED INTEGRAL ABUTMENTS AT BFUDGE SITES WITH SHALLOW BEDROCK BY

The advantages of constructing bridges with integral abutments are recognized by transportation agencies worldwide. However, pile supported integral abutments are limited to locations where the depth of overburden can provide fixed support conditions. In Maine, there are often cases where the depth to bedrock prohibits integral abutment bridges from being used. The goal of this research is to determine the feasibility of constructing integral abutments in conditions that cannot provide the fixed support conditions that are traditionally assumed. A finite element model was created that incorporates realistic constitutive and surface interaction models. These models allow for a good prediction of the soil/structure interaction and the structural response. Three critical model responses were identified: pile stresses, pile kinematics, and pilelbedrock interaction. These responses were examined in later parametric studies, which investigated how changes in girder length, pile length, loading, geometry, member properties, and subsurface conditions influenced the pile responses. It was shown that for piles less than 4 m in length on bedrock, the tip of the pile rotates but does not translate horizontally or vertically. This is similar, in principle, to