Cross-laminated timber (CLT) is an engineered wood material that was introduced in the last decade as a promising candidate for building wood structures higher than 10 stories. Thus far, a handful of tall residential CLT buildings have been built in low seismic regions around the world...
This Design and Construction Guide (the Guide) provides the U.S. design and construction community with guidance to ensure safe, predictable, and economical use of NLT. It is intended to offer practical strategies, advice, and guidance, transferring knowledge and lessons learned from NLT project experience.
This Guide focuses on design and construction considerations for floor and roof systems pertaining to U.S. construction practice and standards. While NLT is being used for vertical elements for walls, stair shafts, and elevator shafts, this Guide provides the greatest depth of direction for more common horizontal applications. The information included here is supplemental to wood design and construction best practices and is specific to the application of NLT. Built examples are included to illustrate real application and visual reference as much as possible.
This Design and Construction Guide (the Guide) provides the Canadian design and construction industry with immediate support and guidance to ensure safe, predictable, and economical use of NLT. It is intended to offer practical strategies, advice, and guidance, transferring knowledge and lessons learned from those with experience.
This Guide focuses on design and construction considerations for floor and roof systems pertaining to current Canadian construction practice and standards. While NLT is being used for vertical elements for walls, stair shafts, and elevator shafts, this Guide provides the greatest depth of direction for common horizontal applications. The information included here is supplemental to wood design and construction best practices and is specific to the application of NLT. Built examples are included to illustrate real application and visual reference as much as possible.
Nail-laminated timber-concrete composite (TCC) is a system composed of a nail-laminated timber (NLT) panel connected to a concrete slab through shear connections. When used as flexural elements such as floors, the concrete and NLT are located in the compression and tension zones, respectively...
Cross-laminated timber (CLT) is an emerging engineered wood product in North America. Past research effort to establish the behaviour of CLT under extreme loading conditions has focussed CLT slabs with idealized simply-supported boundary conditions. Connections between the wall and the floor systems above and below are critical to fully describing the overall behaviour of CLT structures when subjected to blast loads. The current study investigates the effects of “realistic” boundary conditions on the behaviour of cross-laminated timber walls when subjected to simulated out-of-plane blast loads. The methodology followed in the current research consists of experimental and analytical components. The experimental component was conducted in the Blast Research Laboratory at the University of Ottawa, where shock waves were applied to the specimens. Configurations with seismic detailing were considered, in order to evaluate whether existing structures that have adequate capacities to resist high seismic loads would also be capable of resisting a blast load with reasonable damage. In addition, typical connections used in construction to resist gravity and lateral loads, as well as connections designed specifically to resist a given blast load were investigated. The results indicate that the detailing of the connections appears to significantly affect the behaviour of the CLT slab. Typical detailing for platform construction where long screws connect the floor slab to the wall in end grain performed poorly and experienced brittle failure through splitting in the perpendicular to grain direction in the CLT. Bearing type connections generally behaved well and yielding in the fasteners and/or angles brackets meant that a significant portion of the energy was dissipated there reducing the energy imparted on the CLT slab significantly. Hence less displacement and thereby damage was observed in the slab. The study also concluded that using simplified tools such as single-degree-of-freedom (SDOF) models together with current available material models for CLT is not sufficient to adequately describe the behaviour and estimate the damage. More testing and development of models with higher fidelity are required in order to develop robust tools for the design of CLT element subjected to blast loading.
