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.
FINITE ELEMENT ANALYSIS OF 3D-MODEL OF TURNING TABLES OF MICRO-CONTROLLER BASED VERSATILE MACHINE TOOLS DESKTOP LEARNING MODULE
In this paper, we present the results of finite element analysis (FEA) performed to investigate nature of stress and their distribution at optimum point along the two turning tables of a micro-controller based versatile machine tool desktop learning module. Commercial Autodesk Inventor was used to create both three-dimensional (3-D) and 2-D models as well as performing simulation. Dynamics simulation generated the motion load expected to act on the tables when used for real-life operation which were in turn used to perform FEA. The motion of the dc servo motor driving the tables and other parts of the module is designed to be controlled by programmable chips. Before creating FEA simulation for the tables, numerical divergence were prevented by varying the mesh settings to obtain the settings at which the results of the analyses converges which was obtained at 0.03 average element size and 0.04 minimum element size. Finite element analysis carried out on the tables shows that aluminium alloy 4032-T6 chosen will serve in the fabrication of physical prototype. FEA revealed the nature and level of stresses that will be experienced on the tables, it also revealed region where these stresses will concentrate on them. The analysis also estimated the expected weight of the turning tables 1&2 to be 1.23536 to 0.257182 Kg respectively and show that the minimum factor of safety was constantly 15 ul within the tables which shows that they will not fail during operation.
Lateral buckling strengths of cold-formed rectangular hollow sections
Abstract Code rules for designing steel beams against lateral buckling which are based on data for hot-rolled I-sections are unnecessarily conservative when used for cold formed rectangular hollow section beams. Cold-formed rectangular hollow section beams have different stress-strain curves, residual stresses, and crookedness and twist. The effects of residual stress on the inelastic buckling of I-section beams are not nearly as pronounced for hollow sections with two webs, while the strengthening effects of pre-buckling deflections are greater for hollow sections. Simplistic code rules for top flange loading are very conservative when applied to hollow sections. This paper reviews elastic lateral buckling behaviour and the strength rules used to design steel beams. It develops realistic models for cold-formed rectangular hollow beams which are analysed to predict the effects of moment distribution, load height and yield stress on their strengths. The results of the analyses are used to develop improved design rules which remove much of the conservatism of present design rules.