Applications of Finite Element Analysis in Structural Engineering
Advances in the field of computer aided engineering during the last two decades have been quite extensive and have led to considerable benefits to many engineering industries. In the building industry, use of advanced finite element tools has not only allowed the introduction of innovative and efficient building products, but also the development of accurate design methods. High performance computing facilities and advanced finite element programs are now available for research and development activities in many universities in collaboration with industries. In this paper, four examples of successful applications of advanced computer tools are presented and discussed. The structural performance of steel cladding systems, innovative hollow flange beams, plasterboard lined cold-formed steel stud walls and an innovative cold-formed steel building system was accurately simulated by finite element models and thus considerably reduced the number of time consuming and expensive large scale experiments required. Both local and overall failures of various building components were investigated. New design rules, structurally improved and optimized building products and systems, and simplified behavioural and computer models were developed. This paper presents a summary of the four detailed investigations using advanced finite element tools, and selected results.
Wind loading failures of corrugated roof cladding
To investigate possible fatigue damage caused by wind loading, a variable-amplitude loading distribution was developed and applied to a two-span laboratory model of screw-fixed corrugated roof-cladding. It was found that the Miner cycle-ratio summation did not provide a reliable estimate of the fatigue life of the cladding-fastener assembly. More consistent results were obtained by summing cycle-ratios separately over crack initiation and crack propagation periods. The order of application of various load ranges was found to be a major parameter affecting the duration to failure. The laboratory results confirmed that the magnitude and duration of cyclonic wind loading, typical of that produced by cyclone Tracy, could cause fatigue failure of screw-fixed corrugated roof cladding. It is also concluded that the Australian wind-loading code may underestimate wind speeds within suburban areas. In an attempt to simulate the effects of random wind loadings on roof claddings, a variable-amplitude loading distribution and a sequence of load application have been recommended.
Far-field dispersal modeling for fuel-air-explosive devices
A computer model for simulating the explosive dispersal of a fuel agent in the far-field regime is described and is applied to a wide variety of initial conditions to judge their effect upon the resulting fuel/air cloud. This work was directed toward modeling the dispersal process associated with Fuel-Air-Explosives devices. The far-field dispersal regime is taken to be that time after the initial burster charge detonation in which the shock forces no longer dominate the flow field and initial canister and fuel mass breakup has occurred. The model was applied to a low vapor pressure fuel, a high vapor pressure fuel and a solid fuel. A strong dependence of the final cloud characteristics upon the initial droplet size distribution was demonstrated. The predicted fuel-air clouds were highly non-uniform in concentration. 18 refs., 86 figs., 4 tabs.