Prediction of long-term serviceability behavior of a prestressed BOX girder bridge under fatigue action. A case study on AWASH bridge

Abstract

In bridge design, engineers strive to plan an economical structure that will safely transmit loads to the ground without collapsing or deforming excessively. Since it is difficult to predict the exact loading and circumstances that a bridge must withstand, all bridge designs include a substantial margin of safety. Design standards vary throughout the world, but all aim at ensuring that constructed bridges will provide many years of service and will maintain an adequate margin of safety against failure. Bridges are mainly faced to the problem of fatigue from cyclic loading condition which in turn affects the future serviceability and performance of bridge. The future service ability related behavior of bridge includes loss of internal stresses, deflection and crack. PSC Bridges of longer span often exhibit larger long-term serviceability related problems than it was assumed in the design calculation. The future serviceability and performance check for PSC Bridge involves a number of steps which involves tedious and complex calculations due to the presence of variable moving loads and other environmental factors applied over service life of bridge. In line with this, this thesis is focused on prediction of long term serviceability behavior of a prestressed AWASH Bridge under a fatigue action starting from opening of traffic (December 2014) to the end of 2030. In this case the problem is only for long term behavior of un-cracked girder under fatigue action during its operational period. The prediction is done using MATLAB, and MATHCAD PRIME spread sheet and it is shown on appendix.