Column buckling tests

In column buckling tests particular care has to be taken with setting up the column s end support conditions and with the axial or eccentric alignment of the end compressive forces. In order to reduce force alignment difficulties, buckling tests are often carried out in universal testing machines with extended daylights. Simply supported end conditions have been simulated in some tests by means of a steel ball located between two thick steel plates, as shown in Fig. 13.20(a). For column tests which require simply supported... 

Most composites are available as relatively thin laminated sheets, so that tensile type specimens 2 mm to 4 mm thick arc not suitable for compression tests, as they fail by Euler column buckling. Three approaches have been used to avoid specimen buckling ... 

Finally, beams and columns were confined with straps (1 layer) to prevent excessive buckling of the 2-layer horizontal and longitudinal straps during the tests. 

Find the creep buckling curve P as a function of time for a pinned-pinned column made from a polymer material with data given in Figure 4.14 for a o = 2000 psi creep test. 

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