Punching and fatigue behavior of long-span prestressed concrete deck slabs

This paper investigates experimentally the punching and fatigue strength of long-span prestressed concrete deck slab used in simplified composite bridge systems exhibiting a minimum number of girders. Ten one-third scale models were fabricated and six of them were subjected to quasi-static test to find the punching strength and verify the validity of available punching formulas. The other models were tested for fatigue strength using moving wheel load to derive a reliable fatigue formula. The test results show that the predictions of the punching formulas considering the effect of prestressing are reasonable and conservative with the formula from Eurocode 2 being the most practical in the design point of view. Fatigue test results reveal that the fatigue strength of the prestressed concrete deck slab is lower than the prediction from the fatigue formula modified from the formula for a reinforced concrete deck slab. Based on the fatigue test results, this paper proposes a design formula for the fatigue strength of long-span prestressed concrete deck slab.