Analysis and design of single span military bridge using aluminium alloy

Military bridge is an important asset for mobility support in the military operations or during natural disaster. Malaysia still relies on foreign technology because the
country is still not capable in producing our own military bridge. The objective of this research is to design a suitable single span military bridge structure for the
intended purpose using 6061-T6 aluminium alloy as the main material. The bridge is a girder type with 41.1 m length, 4 m width, 1.5 m depth and has the capacity to carry a Pendekar tank vehicle load which is classified as MLC 70. The design of the military bridge is based on operational requirements provided by the Malaysian Army and as outlined in Trilateral Design and Test Code (TDTC) for Military
Bridge and Gap Crossing Equipment. The girder is preliminary designed by limit states checking based on Eurocode 9: Design of Aluminium Structures and the optimized design are done by Finite Element Analysis (FEA) using MSC PATRAN/NASTRAN simulation software. Structural test was conducted on available girder to validate the simulation works. The testing complied to all procedures as explained in the TDTC. Analysis and design results show that the
girder produced safe values of maximum stresses, deflection, buckling and torsion. The additional analysis performed on hybrid girder found that the hybrid girder is capable to withstand heavier load. Structural test results show lower value than results from simulation, which is proven sufficient and reasonable save margin is available between simulation and test outcome. This research has obtained its
objectives and justified that military bridge structure can be designed using locally available materials.