Lateral buckling test

An alternative approach, used by Turvey and Brooks (1996), involved bonding two small aluminium cantilevers normal to the web of the WF beam. Aluminium rods at the ends of the cantilevers extended for a short distance parallel to the web of the beam. These rods provided the lines of contact for long, PVC shoes placed over the ends of three extensometers (two vertical and one horizontal). Figure 13.18 shows an image of the cantilevers and the transducers with their PVC shoes. The two vertical transducers enabled the vertical deflection and the cross-section rotation to be determined and the horizontal transducer recorded the lateral translation of the beam directly. In later lateral buckling tests an electronic clinometer was also attached either to one of the beam s flanges or to its web to record the cross-section rotation directly. 

Turvey G J (1996a), Lateral buckling tests on rectangular cross-section pultruded GRP cantilever beams. Composites B, Vol. 27B, No. 1, pp. 35-42. 

Turvey G J and Brooks R J (1996), Lateral buckling tests on pultruded GRP I-section beams with simply supported-simply supported and clamped-simply supported end conditions. In Proceedings of the 1st International Conference on Composites in Infrastructure (ICCI 96), University of Arizona, Tucson, AZ, pp. 651-664. 

Under compression loading, the long flexible tension specimens would simply buckle. Thus, lateral support to prevent buckling is necessary as shown in the compression test fixture with side-support plates in Figure 2-24. There, the specimen is essentially as long as the fixture is tall, and only a small portion of the specimen can be seen where it is not supported. 

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