The following topics in the field of seismic analysis and design of mid-rise (5- and 6-storey) wood-frame buildings are included in this paper: Determination of the building period, linear dynamic analysis of wood-frame structures, deflections of stacked multi-storey shearwalls, diaphragm classification, capacity-based design for woodframe...
Lack of research and design information for the seismic performance of balloon-type CLT shear walls prevents CLT from being used as an acceptable solution to resist seismic loads in balloon-type mass-timber buildings. To quantify the performance of balloon-type CLT structures subjected to lateral loads and create the research background for future code implementation of balloon-type CLT systems in CSA O86 and NBCC, FPInnovations initiated a project to determine the behaviour of balloon-type CLT construction. A series of tests on balloon-type CLT walls and connections used in these walls were conducted. Analytical models were developed based on engineering principles and basic mechanics to predict the deflection and resistance of the balloon-type CLT shear walls. This report covers the work related to development of the analytical models and the tests on balloon-type CLT walls that the models were verified against.
Advanced Wood-Based Solutions for Mid-Rise and High-Rise Construction: Structural Performance of Post-Tensioned CLT Shear Walls with Energy Dissipators
The latest developments in seismic design philosophy have been geared towards developing of so called "resilient" or "low damage" innovative structural systems that can reduce damage to the structure while offering the same or higher levels of safety to occupants. One such innovative structural system is the Pres-Lam system that is a wood-hybrid system that utilizes post-tensioned (PT) mass timber components in both rigid-frame and wall-based buildings along with various types of energy disspators. To help implement the Pres-Lam system in Canada and the US, information about the system performance made with North American engineered wood products is needed. That information can later be used to develop design guidelines for the designers for wider acceptance of the system by the design community.Several components influence the performance of the Pres-Lam systems: the load-deformation properties of the engineered wood products under compression, load-deformation and energy dissipation properties of the dissipators used, placement of the dissipators in the system, and the level of post-tensioning force. The influence of all these components on the performance of Pres-Lam wall systems under gravity and lateral loads was investigated in this research project. The research project consisted of two main parts: material tests and system tests.
Although not yet seen as common practice, building with cross laminated timber (CLT) is gaining momentum in North America. Behind the scenes of the widely publicized project initiatives such as the Wood Innovation Design Centre Building in Canada and the...
The use of cross-laminated timber (CLT) in residential and non-residential buildings is becoming increasingly popular in North America. While the 2016 supplement to the 2014 edition of the Canadian Standard for Engineering Design in Wood, CSAO86, provides provisions for CLT structures used in platform type applications, it does not provide guidance for the in-plane...
Cross-laminated timber (CLT) products are gaining popularity in the North American market and are being used in midrise wood buildings, in particular, in shearwall applications. Shearwalls provide resistance to lateral loads such as wind and earthquake loads, and therefore it is important to gain a better understanding of the behavior of CLT shearwall systems during earthquake events. This paper is focused on the seismic performance of connections between CLT shearwall panels and the foundation. CLT panels are very stiff and energy dissipation is accomplished by the connections. A literature review on previous research work related to damage prediction and assessment for wood frame structures was performed. Furthermore, a test program was conducted to investigate the performance of CLT connections subjected to simulated earthquake loads. Two different brackets in combination with five types of fasteners were tested under monotonic and cyclic loading protocols. In total, 98 connection tests were conducted and the monotonic load-displacement curves and hysteretic loops were obtained. In this paper, an energy-based cumulative damage assessment model was calibrated with the CLT connection test data. Finally, a correlation between the damage index and physical damage is provided.
Wood-frame is the most common construction type for residential buildings in North America. However, there is a limit to the height of the building using a traditional wood-frame structure. Cross-laminated timber (CLT) provides possible solutions to mid-...