EVALUATION OF LIVE LOAD DISTRIBUTION FOR MOMENT IN NEXT BEAM BRIDGE

摘要

Currently, the live load distribution factors (LLDF) for the northeast extreme tee (NEXT) beam bridges are calculated on the basis of AASHTO equation for each beam stem, then two LLDFs from each stem are added together and applied to the entire beam, which may lead to an over-conservative design. This paper employed a 3-D finite element (FE) modeling of an entire NEXT beam bridge to evaluate the live load distribution for moment in each beam. FE results were compared to the manual solution based on the AASHTO LRFD Bridge Design Specifications, which indicated that using AASHTO type ”k” live load distribution factor for moment in interior beam could lead to a safe design of 8ft-wide NEXT beams, for both exterior and interior girders.