Behaviour of U Profile Steel Beam Under Torsion Loading – Length Effect

conference paper

English

Within the framework of standard prescriptions, the problems of the design and evaluation of beams under torsion find only marginal solution. The overall development of theoretical approaches and analyses of reliability assessment of supporting structures finds application in standardization documents. With the aim to contribute to the European methodology of the design of steel structures according to their limit states, the studies have to be based on recent knowledge of loading and materials. This tends authors to observe behaviour of open section thin walled beam under torsion moment. The steel beams under tensional loading explicit best characteristic of load carrying capacity and displacement. Its why in design we expedite tensile type of loading. Less efficient is compression and bending. Even worst is action of torsion moment. Structure under relatively low torsion moment shows very large displacement. Some times we need to design beam supporting torsion moment, commonly some auxiliary structures. But overloading even of auxiliary structures can lead to huge damages. In steel civil engineering structures design code is not shown the procedure of designing beam under torsional moment. We need to follow basic formula of beam theory. The problem can be more complex when torsion moment acts together with other basic beam load for example bending moment. In this occasions load carrying capacity of bended beam is negatively affected by torsion moment presence. The influence of a steel beam length on its load-carrying capacity in torsion will be studied. The UPE 200 profile beam was modeled by the finite element method using of the ANSYS programme. The finite element model can be seen on figure 1. The load-carrying capacity was calculated by a geometrically and materially nonlinear solution. The load-carrying capacity of beams with lengths by degrees L=0.1 m; 0.2 m; 0.5 m; 1.0 m; 2.0 m. One end of beam was fixed and on second torsion moment acts as linearly distributed pressure on web surface. Two cases for all lengths were analysed – with warping forbidden and permitted. Load carrying capacity of beam with forbidden warping reach twice-higher value.

torsional load carrying capacity, warping of section, nonlinear finite element method analysis, highly distorted structure computing

KALA, Z., KALA, J.

2004

19. 5. 2004

Vilnius (Lithuania)

9986-05-722-1

8th Int. Conference Modern Building Materials, Structures and Techniques

223

228

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