Evaluation of in-plane shear performance of CLT using the asymmetric four-point bending test method and detailed examination of the method

The use of cross-laminated timber (CLT) and laminated veneer lumber (LVL) in wooden structures including non-residential, tall and large buildings is increasing, even though they might be subjected to important horizontal forces. The asymmetric four-point bending test method, originally used for lumber and glulam, can be used to evaluate the in-plane shear performance of CLT. This test may have led to bending failure in the case of the CLT specimens. In this study, asymmetric four-point bending tests were conducted to evaluate appropriate shear strength and modulus. Span ratio of 0.5–1.0 is recommended for shear failure to occur as the latter is less affected by compression force. The shear strength exhibited a positive correlation with the ratio of the perpendicular layer, suggesting that the shear strength can be easily estimated. The diagonal measurement of shear deformation is a convenient method because it has less effect on deformation due to the direction of the grain.