Fatigue in concrete decks of cable supported bridges

Abstract

Fatigue in cable supported concrete decks of bowstring girder, network arch, and cable-stayed bridges are discussed. Stress concentration at the cable anchorage locations, and prestress anchorage locations need careful analysis. Overstress in inferior quality concrete, even in localized region, is likely to be aggravated due to the higher fatigue loading. Therefore, it is necessary to use high strength better quality controlled concrete. It is brought out that due to suitable prestressing of the deck slab in the longitudinal direction, compressive strength of the concrete in the transverse direction goes up by 18-25%. In the cases of existing bow string girder bridges having reinforced concrete deck slab system, external prestressing in the longitudinal direction is essential. Similarly, in the case of cable stayed bridges having concrete deck slab, cross prestressing of the central panel using additional cables, and transverse prestressing are required. © 2008 Taylor & Francis Group.