Shear-Through-Thickness Properties of Wood-Based Panels Determined by the Two-Rail Shear and the Edgewise Shear Methods

摘要

Importance of the shear properties of wood-basedpanels has been increasing due to trends toward building codeperformance standardization of the building code in Japan.Shear-through-thickness properties of the panel materials, whichare not defined in either the JIS and the JAS standards, wereevaluated by the two-rail shear (TRS) and the edgewise shear(EWS) methods. Shear strength (#tau#) and modulus of rigidity(G) were determined for three types of panels used as structuralmaterials in housing; particleboard (PB), softwood plywood(PW), and oriented strand board (OSB). Comparisons weremade between the panels and between the two test methods. Theresults obtained were summarized as follows:From the samples tested, OSB had the highest shear properties(#tau# and G) and PW had the lowest, while PW had the highestbending properties. High shear properties in OSB could be dueto its degree of strand alignment and the layer structure. Wire-strain gauge was used for measuring strain in the both methods;eight gauges were used for one test piece of the TRS and six forthe EWS test. It was shown that G could be obtained in the EWStest. Although ~ obtained from the TRS method were larger thanthose from EWS method for all panel types, Gs from the TRSmethod were almost comparable to those from the EWS. Linearrelationships were found between shear properties from the TRSmethod and those from the EWS method. These resultssuggested the possibility of employing the EWS test as analternative method for TRS.