Skip header and navigation

5 records – page 1 of 1.

Behaviour of Glued-Laminated (Glulam) Beams and Columns Subjected to Simulated Blast Loads

https://research.thinkwood.com/en/permalink/catalogue1549
Year of Publication
2016
Topic
Mechanical Properties
Material
Glulam (Glue-Laminated Timber)
Application
Beams
Columns
Author
Lacroix, Daniel
Doudak, Ghasan
Year of Publication
2016
Country of Publication
Austria
Format
Conference Paper
Material
Glulam (Glue-Laminated Timber)
Application
Beams
Columns
Topic
Mechanical Properties
Keywords
Blast Loads
Static Loads
Dynamic Loads
Dynamic Tests
Language
English
Conference
World Conference on Timber Engineering
Research Status
Complete
Notes
August 22-25, 2016, Vienna, Austria p. 1199-1206
Summary
This paper presents preliminary results from an experimental program investigating the dynamic behaviour of glulam beams and columns subjected to simulated blast loads. A total of eight glulam beams and columns were tested destructively under static and dynamic loads. Based on the dynamic tests conducted on the beams, an increase in strength under dynamic loading, relative to that measured under the static loading, was observed. A material predictive model that accounts for high strain-rate effects is developed. The experimental displacement-time histories were reasonably well predicted through a single-degree-of-freedom approach which used the proposed resistance model as input.
Online Access
Free
Resource Link
Less detail

Blast-Resistant Testing for Loaded Mass Timber Structures

https://research.thinkwood.com/en/permalink/catalogue843
Topic
Mechanical Properties
Material
CLT (Cross-Laminated Timber)
Application
Walls
Organization
Forest Products Laboratory
Country of Publication
United States
Format
Report
Material
CLT (Cross-Laminated Timber)
Application
Walls
Topic
Mechanical Properties
Keywords
Exterior Walls
Blast Loads
Protection
Research Status
In Progress
Summary
Opening new markets for the use of CLT that can capitalize on the strength and speed of construction allowed by the technology creates the best opportunity for wood product market growth. One such market is the Department of Defense (DoD), representing an estimated 148 million board feet of additional lumber production. Wood products have been significantly under-represented in the DoD construction market because of their perceived performance in blast conditions. The objectives of this project are to develop a design methodology and to demonstrate performance for exterior bearing CLT walls used in buildings subject to force protection requirements. This methodology should be published by U.S. Army Corp of Engineers – Protective Design Center to be used by engineers for designing CLT elements to withstand blast loads as determined by code requirements and specific project conditions.
Resource Link
Less detail

Development of a Cost-Effective CLT Panel Capable of Resisting DOS/DOD Design Basis Threats

https://research.thinkwood.com/en/permalink/catalogue2582
Topic
Mechanical Properties
Material
CLT (Cross-Laminated Timber)
Application
Ceilings
Floors
Walls
Organization
Karagozian & Case
Country of Publication
United States
Material
CLT (Cross-Laminated Timber)
Application
Ceilings
Floors
Walls
Topic
Mechanical Properties
Keywords
Ballistic Resistance
Blast Loads
Cost Effective
Research Status
In Progress
Notes
Project contact is Mark Weaver at Karagozian & Case
Summary
Buildings for the U.S. Department of State (DOS) and U.S. Department of Defense (DOD) often have to meet blast as well as forced entry / ballistic resistance (FE/BR) design requirements to mitigate the hazardous effects associated with terrorism. Historically, DOS and DOD buildings exposed to these threats have been constructed using concrete and steel. However, the emergence of cross-laminated timber (CLT) presents an opportunity to provide a sustainable building material alternative to owners and architects developing such structures. Several wood characteristics (i.e., propensity to rupture in a brittle fashion upon being overstressed, relatively low penetration resistance) serve to limit CLT’s effectiveness in resisting blast and FE/BR threats. The proposed effort seeks to address these limitations by investigating the possibility of incorporating commercial off-the-shelf (COTS) building materials into CLT panel designs in order to meet DOS/DOD blast and FE/BR design requirements. Particular emphasis will be placed on ensuring the developed panel designs are cost competitive to facilitate their inclusion in actual buildings. The project team includes an American CLT manufacturer to quickly assess the cost impacts of incorporating COTS materials into CLT panel layups. Additionally, representatives from the DOS, DOD, and an architecture firm routinely involved with the design of DOS buildings will be consulted to ensure programmatic, aesthetic, and detailing issues are considered during candidate panel design development. 
Less detail

Effect of Realistic Boundary Conditions on the Behaviour of Cross-Laminated Timber Elements Subjected to Simulated Blast Loads

https://research.thinkwood.com/en/permalink/catalogue2361
Year of Publication
2017
Topic
Seismic
Material
CLT (Cross-Laminated Timber)
Application
Floors
Walls
Author
Cote, Dominic
Publisher
University of Ottawa
Year of Publication
2017
Country of Publication
Canada
Format
Thesis
Material
CLT (Cross-Laminated Timber)
Application
Floors
Walls
Topic
Seismic
Keywords
Connections
Seismic Load
Blast Loads
Fasteners
Language
English
Research Status
Complete
Summary
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.
Online Access
Free
Resource Link
Less detail

Flexural Response of Glued Laminated (Glulam) Beams Subjected to Blast Loads

https://research.thinkwood.com/en/permalink/catalogue492
Year of Publication
2014
Topic
Mechanical Properties
Material
Glulam (Glue-Laminated Timber)
Application
Beams
Author
Lacroix, Daniel
Viau, Christian
Doudak, Ghasan
Year of Publication
2014
Country of Publication
Canada
Format
Conference Paper
Material
Glulam (Glue-Laminated Timber)
Application
Beams
Topic
Mechanical Properties
Keywords
Strain
Flexural Behaviour
Blast Loads
Language
English
Conference
World Conference on Timber Engineering
Research Status
Complete
Notes
August 10-14, 2014, Quebec City, Canada
Summary
An extensive body of research is currently available on the behaviour of concrete and steel structures when subjected to blast threats, however, little to no details on how to address the design or retrofitting of wood structures are available. In this paper, preliminary results, both experimental and analytical, are presented on the flexural behaviour of glulam beams under high strain rates. A total of three 80 mm x 228 mm x 2,500 mm glulam beams with a clear span of 2,235 mm were subjected to simulated blast loads using a shock tube. The preliminary experimental results showed that a brash tension failure mode was observed on the tension laminate. It was also shown that a simplified SDOF model, using linear elastic resistance curves, was capable of predicting the failure displacement and level of damage with reasonable accuracy.
Online Access
Free
Resource Link
Less detail