Experimental Investigation of Controlled Rocking Cross-Laminated Timber Walls

Abstract

Controlled rocking timber walls are being developed to resist earthquake loads without major structural damage. These systems respond to seismic loading through partial uplift from the foundation, dissipating energy through rocking impact and supplemental energy dissipation elements. Initial research and construction of these walls typically used Laminated Veneer Lumber (LVL); however, Cross-Laminated Timber (CLT) is increasing in popularity for controlled rocking timber walls, particularly in the North American market. Since the use of CLT in a rocking system is relatively new, it is important to understand how CLT behaves in this application. In particular, the area near the rocking toe is a critical region in a controlled rocking CLT wall, and the local deformations and strain distributions around the rocking toe are not yet well understood. To address this issue, this thesis presents the results of an investigation of large-scale controlled rocking CLT walls subjected to quasi-static reverse-cyclic loading. The test specimens vary in terms of aspect ratio and applied axial load, so as to quantify how these differences affect the strain distribution in the rocking toe region at increasing levels of drift. The ndings from this experimental procedure will aid in the understanding of current design models, as well as the development of better numerical models of the rocking toe, which are critical for the design and analysis of controlled rocking CLT walls.