Experimental and Numerical Investigation on the Lateral Performance of Screwed Midply-Bamboo Shear Walls

This paper presents an experimental and numerical investigation of the lateral performance of screwed midply-bamboo shear walls. In these shear walls, plybamboo panels and wood screws were used as the middle sheathing and fasteners, respectively, with a newly developed U-shaped steel connector used as the hold-down component. Both monotonic and cyclic tests were conducted to evaluate the failure mechanisms and mechanical properties of the walls. Test results indicated that the combined use of plybamboo sheathings and wood screws significantly reduced the failures of sheathing crushing and fastener withdrawal. The U-shaped hold-down enabled the tension end stud to rotate freely without undesirable bending-tensile fractures. The shear strength of the walls exceeded that of existing midply wood shear walls by over 50% and was more than 2.5 times that of comparable standard shear walls constructed with plybamboo sheathings and wood screws. However, in practical implementations, the vertical boundary members of the walls require sufficiently large cross-sectional dimensions and reliable interconnections to prevent premature buckling. In addition, to avoid screw fatigue fractures under design-level seismic loads, the walls’ interstory drift is recommended to be limited to 1.8%. Numerical models of the walls were subsequently established in a half-section configuration using the software OpenSeesPy. Comparative analysis demonstrated that the proposed model can reasonably and efficiently predict the load-carrying capacity and accurately capture the hysteretic characteristics of the walls. This study provides experimental and theoretical support for the feasibility of screwed midply-bamboo shear walls in timber construction scenarios requiring superior lateral loading resistance.