Short answer
When designing with cross-laminated timber, account for the synergistic effect of rolling shear and tension perpendicular to grain stresses to ensure structural integrity.
- Field
- Final Production
- Source
- cIRcle (University of British Columbia) (2015)
- Method
- Experimental and Analytical Modelling
- Evidence
- Strong effect
The failure of cross-laminated timber (CLT) under load is not solely due to rolling shear stress, but rather a combination of rolling shear and tension perpendicular to the grain. This final production research insight is drawn from a 2015 study published in cIRcle (University of British Columbia). Using Experimental and analytical modelling, researchers explored how this design variable affects real-world outcomes. The key design takeaway: When designing with cross-laminated timber, account for the synergistic effect of rolling shear and tension perpendicular to grain stresses to ensure structural integrity.
Rolling Shear Failure in Cross-Laminated Timber is a Combined Stress Phenomenon
The failure of cross-laminated timber (CLT) under load is not solely due to rolling shear stress, but rather a combination of rolling shear and tension perpendicular to the grain.
cIRcle (University of British Columbia) · 2015
Key Findings
- 01Tension perpendicular to grain stress, in conjunction with rolling shear stress, contributes to cross-layer failure in CLT.
- 02Experimental results validated the analytical models, showing failure modes consistent with combined stress effects.
Application
Design takeaway
When designing with cross-laminated timber, account for the synergistic effect of rolling shear and tension perpendicular to grain stresses to ensure structural integrity.
How to apply
In structural design calculations for CLT, incorporate models that account for both rolling shear and perpendicular-to-grain tensile stresses. Evaluate manufacturing parameters like clamping pressure for their impact on material performance.
Project actions
- 01When testing materials, consider using high-speed cameras to capture rapid failure events.
- 02Combine analytical modelling with physical testing to validate findings and understand complex failure mechanisms.
Method & Evidence
Variables
Strengths & Limitations
Strengths
- +Combines analytical modelling with experimental validation.
- +Utilizes high-speed imaging to capture failure events.
Limitations
The specific type and thickness of CLT used in the study might not apply to all CLT products. The environmental conditions during testing were not extensively varied.
Reliability & validity
The use of analytical models alongside experimental testing enhances the validity of the findings. Reliability would depend on the consistency of the CLT material and the precision of the testing equipment.
Think critically
How might variations in wood species, adhesive type, or panel layup affect the dominance of rolling shear versus tension perpendicular to grain in CLT failure?
Design Principles
"Structural components should be designed to withstand the combined stresses predicted by their intended use, rather than relying on single-mode failure analysis."
Understanding the combined stress failure mechanism is crucial for accurate structural design and material selection in mass timber construction. This insight allows for more robust engineering of CLT panels, preventing premature failure and ensuring the long-term performance and safety of buildings.
What This Means for Your Design
When wood panels are glued together to make strong building materials (like CLT), they can break in a way that's a mix of sliding and pulling apart. Designers need to think about both ways of breaking to make sure buildings are safe.
How to use in your project
- 1.Use this research to justify the investigation of combined stress failure modes in your own material testing or design analysis.
Add to My Project
Quick Cite
Paragraph starter
This research demonstrates that the failure mechanism of cross-laminated timber (CLT) is a complex interaction, specifically identifying that rolling shear failure is often accompanied by tension perpendicular to grain stress. This combined stress phenomenon is critical for understanding the material's performance limits and ensuring structural safety in design applications.
Source
cIRcle (University of British Columbia)
Failure mechanism of rolling shear failure in cross-laminated timber
journal · 2015
View sourceQuestions About This Research
- What does the research say about rolling shear failure in cross-laminated timber is a combined stress phenomenon?
- When designing with cross-laminated timber, account for the synergistic effect of rolling shear and tension perpendicular to grain stresses to ensure structural integrity. Evidence: cIRcle (University of British Columbia) (2015).
- Why does "Rolling Shear Failure in Cross-Laminated Timber is a Combined Stress Phenomenon" matter for design?
- Understanding the combined stress failure mechanism is crucial for accurate structural design and material selection in mass timber construction. This insight allows for more robust engineering of CLT panels, preventing premature failure and ensuring the long-term performance and safety of buildings.
- How can designers apply this research?
- When designing with cross-laminated timber, account for the synergistic effect of rolling shear and tension perpendicular to grain stresses to ensure structural integrity.
- What were the main findings?
- Tension perpendicular to grain stress, in conjunction with rolling shear stress, contributes to cross-layer failure in CLT.. Experimental results validated the analytical models, showing failure modes consistent with combined stress effects.
- What research method was used?
- Experimental and Analytical Modelling.
- How strong is the evidence?
- Evidence strength is rated Strong effect, based on a 2015 journal from cIRcle (University of British Columbia).
- What should I do differently in my next project?
- In structural design calculations for CLT, incorporate models that account for both rolling shear and perpendicular-to-grain tensile stresses. Evaluate manufacturing parameters like clamping pressure for their impact on material performance.
- What are the limitations?
- The study focused on specific CLT panel configurations and testing conditions, which may not be representative of all applications.