FATIGUE ANALYSIS OF HIGHWAY BRIDGES

The increased possibility of minor as well as major fatigue failure of highway bridges of relatively short span now being subjected to heavy trucks more frequently than ever before, appears to be a critical problem that calls for a basic reevaluation of the fatigue performance of these bridges constructed under current and past design codes. For the purpose of establishing a framework of the study along this line, the present paper outlines, with a numerical example, a method of sensitivity analysis for the fatigue failure dealing with a system of a simple bridge and moving vehicles. Specifically, the sensitivity of the expected fatigue life to various parameters of the bridge and traffic flow characteristics such as failure criterion, traffic intensity, highway surface roughness, bridge damping, etc. is investigated.