Out-of-plane Shear Strength of CLT with Japanese Larch or Sakharin Fir I.

Abstract

The primary object of this study is to investigate the out-of-plane shear strength property of 5-layer 5-ply CLT (Cross-laminated timber) with Japanese larch (Larix kaempferi) or Sakharin fir (Abies sachalinensis). The secondary object is to determine how the shear strength changes as the shear span increases under different loading conditions. We carried out shear strength tests by two loading methods : a three-point bending test and an asymmetric four-point bending test. We prepared several shear span conditions for each method. Results from these tests are as follows : (1) for both test methods, the shear strength of CLT with Sakharin fir was approximately 30% lower than that of CLT with Japanese larch, (2) for the asymmetric four-point bending test, specimens showed shear fracture at all span conditions, but in the three-point bending test, several specimens of CLT with Japanese larch showed bending fracture at the maximum load, and (3) for both test methods, the shear strength decreased as shear span increased according to a power curve regression. In addition, the converged values are approximately equivalent to the rolling shear strength obtained by the compression method.