Effect of Load Rate on Flexural Properties of Wood-Plastic Composites
Keywords:Rate of loading, bending, strength, stiffness, wood fiber and plastic composites
AbstractWith the increase in wood-plastic composite (WPC) products in the commercial marketplace, it is important that the material properties of WPC products are accurately determined. Many of these products are targeted for use in flexural applications; thus the ability to accurately determine the flexural properties is of critical importance if WPC products are to compete as a structural material. Third-point bending tests were conducted on selected WPC formulations at rates ranging from 4.6 mm/min to 254 mm/min and flexural properties were determined. It was found that rate-of-load effects were present for both modulus of rupture and modulus of elasticity over certain ranges of load rate values. Specifically, significant decreases in flexural properties were observed for load rates slower than 62.5 mm/min.
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