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.
FPInnovations conducted a research project to study the construction of mid-rise wood exit shafts in Ontario and Québec. The scope of the project included an investigation into the concerns that have been raised in regards to the use of wood exits in mid-rise buildings, an analysis of recent Canadian fire statistics...
FPInnovations carried out a survey with consultants and researchers on the use of analytical models and software packages related to the analysis and design of mass timber buildings. The responses confirmed that a lack of suitable models and related information for material properties of timber connections was creating an impediment to the design and construction of this type of buildings. Furthermore, there is currently a lack of computer models and expertise for carrying out performance-based design for wood buildings, in particular seismic and/or fire performance design.
In this study, a sophisticated constitutive model for wood-based composite material under stress and temperature was developed. This constitutive model was programmed into a user-subroutine which can be added to most general-purpose finite element software. The developed model was validated with test results of a laminated veneer lumber (LVL) beam and glulam bolted connection under force and/or fire.
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.
In recent decades, the wood industry has developed a number of innovative mass timber products. Among others, structural composite lumber (SCL) products, such as parallel strand lumber (PSL), laminated strand lumber (LSL) and laminated veneer lumber (LVL...
The CLT Handbook provides vital “How to” information on CLT for the design and construction community, and is a great source of information for regulatory authorities, fire services and others. The CLT Handbook is also a good textbook for university level timber engineering courses. In summary, the Canadian CLT Handbook will remain the most comprehensive reference for sharing the latest technical information on North American CLT.
The Canadian edition of the CLT Handbook, first published in 2011 under the Transformative Technologies Program of the Natural Resources Canada, played an imperative role in accelerating the use and acceptance of CLT in North America. Its introduction subsequently led to the publication of the US Edition. The Canadian Edition supported the early use of CLT products from Canadian manufacturers in many small to large projects across Canada and the US, and paved the way for CLT and other wood products to be used in new applications like tall and large buildings, and bridges.
Since then, additional research has taken place globally and substantial regulatory changes have occurred enabling more wood to be used in construction. Those developments highlighted a need for the CLT Handbook to be updated. The 2019 Edition of the CLT Handbook, for example, augments the recently developed CLT provisions in CSA Standard in Engineering Design in Wood and it includes a design example of an 8-storey CLT building. It helps expand the knowledge base of the designers about CLT enabling them to develop alternative solutions for taller and larger buildings that are beyond the boundaries of the acceptable solutions in building codes.
The U.S. edition of the CLT Handbook is a 572-page guide and is the definitive handbook on cross-laminated timber (CLT), covering manufacturing, structural design, connections, fire and environmental performance and the lifting and handling of CLT elements.
This study provides a comparative life cycle assessment (LCA) of a 4060 m2, 4-storey cross laminated timber (CLT) apartment building located in Quebec City, Canada and an equivalently designed building consisting of reinforced concrete slabs and columns with light gauge steel studded walls (CSSW)...
As part of its research work on wood buildings, FPInnovations has recently launched a Design Guide for Timber-Concrete Composite Floors in Canada. This technique, far from being new, could prove to be a cost-competitive solution for floors with longer-span since the mechanical properties of the two materials act in complementarity. Timber-concrete systems consist of two distinct layers, a timber layer and a concrete layer (on top), joined together by shear connectors. The properties of both materials are then better exploited since tension forces from bending are mainly resisted by the timber, while compression forces from bending are resisted by the concrete. This guide, which contains numerous illustrations and formulas to help users better plan their projects, addresses many aspects of the design of timber-concrete composite floors, for example shear connection systems, ultimate limit state design, vibration and fire resistance of floors, and much more.