Composite army bridges under fatigue cyclic loading

Military composite bridges offer many unique advantages to the army - for example their high strength-to-weight ratio and superior corrosion and fatigue resistance properties - compared to current steel and aluminum bridges. This paper presents the results of part of a comprehensive, on-going research program sponsored by the US Army to develop innovative field repair techniques for military composite bridges. The virtual tests were performed on the composite treadway under four different loading cases: (i) maximum shear static loading case, (ii) maximum bending static loading case, (iii) fatigue progressive failure analysis for the moving load case, and (iv) fatigue progressive failure analysis for the maximum flexural loading case. Results of virtual testing and progressive failure analysis (PFA) simulation conducted on a composite army bridge (CAB) prototype demonstrated a good match with the full-scale laboratory test results conducted in an earlier study. For instance, the variation between the maximum deflections predicted by the GENOA simulation for the maximum shear and those obtained from the full-scale tests was only 3.2%. In addition, the location and type of damages at the ultimate load were very close to those obtained from the full-scale laboratory tests.