An analytical model for Tensairity girders
Uwe Teutsch2009, Symposium of the International Association For Shell and Spatial Structures Evolution and Trends in Design Analysis and Construction of Shell and Spatial Structures Proceedings
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Abstract
An analytical model for the deflection of a symmetric, spindle shaped Tensairity girder under homogenous load is proposed which can be solved analytically. The results are compared to FEM predictions for a specific Tensairity girder. Further simplifications of the analytical solution lead to a simple relation for the deflection of the Tensairity girder, which reveals the importance of the elasticity of the chords relative to the air pressure in the inflated hull. Such simple models are crucial to understand the basic principles of Tensairity and provide the engineer with easy rules to estimate the load-deflection behaviour of this new light weight structure.
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3 1.11 - jsr40-60 approximate assessment of the ultimate longitudinal strength of the hull girder
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A method is presented to estimate the ultimate moment based on a simplified approach to represent the behavior of stiffened plate columns. The assessment of the strength of a very large crude carrier is performed and compared with the moment at failure in hogging estimated by other methods applied to the same case. The proposed method allows the prediction of the degradation of the strength due to corrosion and residual stresses. It also allows the evaluation of the strength of the hull at several heeling conditions. Finally, an analysis of the efficiency of the high tensile steel is carried out. * The elements into which the cross section is subdivided are considered to act and behave independently. 60 MARCH 1996 0022-4502/96/4001-0060$00.45/0 JOURNAL OF SHIP RESEARCH
Analysis method of ultimate hull girder strength under combined loads
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The objective of this study is to propose an analysis method of ultimate hull girder strength under combined bending and torsion. The hull girder is modelled by a series of thin-walled beam elements and the average stress-average strain relationship of plate and stiffened panel elements under axial loads considering the effect of shear stress is implemented in the beam elements. First, a torsional moment is applied to the beam model for a whole model within the elastic range. Then, the ultimate bending strength of cross-sections is calculated applying Smith's method to beam elements considering the warping and shear stresses. The proposed simplified method is applied to the progressive collapse tests of scale models under combined loads. On the other hand, nonlinear explicit finite element method (FEM) is adopted for the analysis of the test models. The effectiveness of the simplified method is discussed comparing with the results of experiments and FEM analysis.
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