Experimental Determination of Compressive Strength of Pultruded Structural Shapes

An existing coupon compression fixture was modified for testing cylindrical coupon samples of pultruded material in compression. Then a new fixture was developed for testing full-size structural shapes, which presents all the advantages of the coupon fixture. Particularly, splitting of the end of the sample is prevented while reducing the stress concentration factor at the ends, yielding compression failures at the center of the specimen. All the fiber reinforcements of structural shapes (CSM, ±45, and roving) were tested individually and combined to support the development of a simple model for compressive strength of structural shapes. A simple formula is developed for prediction of compressive strength of pultruded structural shapes. Comparisons between experimental data and predicted values are presented. Introduction Composite structural shapes are produced by pultrusion, with the geometry and material properties of the cross-section being fixed by the manufacturer. A broad selection of such shapes is offered [1-3]. Composite structural shapes are used because of their high strength