Improvement of Continuity Connection over Fixed Piers Final Rept

摘要

To improve structural efficiency of multi-span simply supported bridges, partial and/or full continuity is provided through cast-in-place concrete diaphragms and decks. These bridges known as Simple-Span Precast Prestressed Bridge Girders Made Continuous are continuous for live loads. This continuity connection is also beneficial from maintenance point of view by eliminating open joints. However, continuity connections also have their own structural, construction, and maintenance shortcomings. Development of positive moments and diaphragm cracking at the internal pier due to time dependent effects of prestressing is a major structural problem that also affects bridge durability and esthetics. Another issue is that due to reinforcement congestion joint construction is time consuming and thus expensive. Furthermore, the degree of continuity varies depending on structural and construction conditions. These problems are common to various design details used by many states in the US.