Fatigue Strength of Joints in a Precast Prestressed Concrete Double Tee Bridge

摘要

align="left">The feasibility of using precast, prestressed double tees to form a monolithic bridge system is examined by conducting static and fatigue load tests on a 1:3.5 scale model of a two-span, transversely and? longitudinally post-tensioned, continuous double tee beam system. Constant amplitude fatigue loading was applied on the model at typical locations simulating HS20-44 AASHTO truck loading. The? behavior of the bridge system was evaluated with regard to structural integrity. Crack widths in the longitudinal and transverse joints were monitored with increasing cycles of fatigue loading. A finite? element analysis of the bridge system was carried out using orthotropic modeling, and the deflections were compared with experimental values. The ultimate load, computed from plastic analysis, was? found to be in good agreement with the measured value. The study established the feasibility and structural adequateness of the precast, prestressed concrete double tee concept for short and medium span? highway bridges in Florida and elsewhere.