Convenient and inexpensive test methods for pultruded GFRP composite materials

Standard test methods for obtaining the mechanical properties of pultruded glass fibre reinforced polymer (pGFRP) composite materials often require specific test fixtures and coupon geometries, leading to an increase in the cost and complexity of test equipment and coupon preparations. Surrogate, theory based calculation of material properties in such cases is often inadequate, resulting in non-conservative values. Significant variation in materials and practice in complex test methods potentially affect the nature of the "characteristic" material properties used in design. In order to establish the most convenient and inexpensive test methods for pGFRP composite materials, both standard and nonstandard test methods that have seen practical applications are discussed regarding their required test fixtures, coupon preparations, limitations and perceived reliability and utility. Only tests for obtaining tensile, compressive and shear strengths and moduli of pGFRP materials are considered, since these mechanical properties are of the most interest to both researchers and designers. Test methods that can be readily conducted using typically available test equipment as well as those requiring simple material preparations are recommended. Simple, although as yet nonstandard test methods are proposed for obtaining transverse material properties for sections from which standard specimens may not be obtained. Furthermore, the recommended test methods are demonstrated in an experimental program and found to yield acceptable results with satisfactory accuracy, while requiring no special test fixtures.