Abstract

Long-span portable beams are very important in military operations for the purpose of rapid construction and bridging system. Such structural element can also be utilized in disaster relief operations. In the early days, portable structure, such as military bridges were made from steel, causing the weight of the structure to be huge, and consequently, it will be costly to operate. To overcome these problems, aluminium and metal alloy were introduced to reduce the weight of such structure. The use of composite material such as carbon fibre reinforced polymer (CFRP) emerges as a lighter alternative and is considered to be the primary material for the portable beam. The use of the CFRP as a primary material is due to its high strength to weight ratio, thus it makes it lighter than steel and other alloys. In this research, a long-span portable beam is analysed and designed using finite element method. Several static simulations, with impact factor for dynamic effect, are made to test various possible lay-ups, including the use of core in order to increase stiffness of the member. From the trials, it can be concluded that with proper design and fabrication, CFRP is capable of carrying the design load similar to steel and aluminium. Furthermore, use of core layers for top flange can improve the performance of the structure significantly, while use of core to the webs stiffen the webs against buckling and further improve the overall performance of the structure.

Key words: Composite material, portable beam, sandwiched composite, finite element analysis.

Abbreviation

CFRP, Carbon fibre reinforced polymer; FRP, fibre reinforced polymer; MLC, military load class; TDTC, trilateral design and test code.