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7 records – page 1 of 1.

Combination of Steel Plate Shear Walls and Timber Moment Frames for Improved Seismic Performance

https://research.thinkwood.com/en/permalink/catalogue2735
Year of Publication
2020
Topic
Seismic
Material
CLT (Cross-Laminated Timber)
Application
Shear Walls
Frames
Author
Iqbal, Asif
Todorov, Borislav
Billah, Muntasir
Year of Publication
2020
Format
Conference Paper
Material
CLT (Cross-Laminated Timber)
Application
Shear Walls
Frames
Topic
Seismic
Keywords
Timber Moment Frames
Steel Plate Shear Walls
Hybrid
Seismic Performance
Interstory Drifts
Conference
World Conference on Earthquake Engineering
Research Status
Complete
Summary
Recent interests in adopting sustainable materials and developments in construction technology have created a trend of aiming for greater heights with timber buildings. With the increased height these buildings are subjected to higher level of lateral load demand. A common and efficient way to increase capacity is to use shearwalls, which can resist significant part of the load on the structures. Prefabricated mass timber panels such as those made of Cross-Laminated Timber (CLT) can be used to form the shearwalls. But due to relatively low stiffness value of timber it is often difficult to keep the maximum drifts within acceptable limit prescribed by building codes. It becomes necessary to either increase wall sizes to beyond available panel dimensions or use multiple or groups of walls spread over different locations over the floor plan. Both of the options are problematic from the economic and functional point of view. One possible alternative is to adopt a Hybrid system, using Steel Plate Shear Walls (SPSW) with timber moment frames. The SPSW has much higher stiffness and combined with timber frames it can reduce overall building drifts significantly. Frames with prefabricated timber members have considerable lateral load capacity. For structures located in seismic regions the system possesses excellent energy dissipation ability with combination of ductile SPSW and yielding elements within the frames. This paper investigates combination of SPSW with timber frames for seismic applications. Numerical model of the system has been developed to examine the interaction between the frames and shear walls under extreme lateral load conditions. Arrangements of different geometries of frames and shear walls are evaluated to determine their compatibility and efficiency in sharing lateral loads. Recommendations are presented for optimum solutions as well as practical limits of applications.
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A Comparative Analysis of Three Methods Used for Calculating Deflections for Multi-Storey Wood Shearwalls

https://research.thinkwood.com/en/permalink/catalogue1719
Year of Publication
2016
Topic
Mechanical Properties
Material
Light Frame (Lumber+Panels)
Application
Shear Walls
Wood Building Systems
Author
Newfield, Grant
Wang, Jasmine
Year of Publication
2016
Format
Conference Paper
Material
Light Frame (Lumber+Panels)
Application
Shear Walls
Wood Building Systems
Topic
Mechanical Properties
Keywords
Deformation
Drifts
Stiffness
Building Period
Base Shear
Conference
World Conference on Timber Engineering
Research Status
Complete
Notes
August 22-25, 2016, Vienna, Austria p. 4597-4604
Summary
With the introduction of 5 and 6-storey wood structures into the National Building Code of Canada 2015, it is important that guidance be provided to engineers to ensure that a reasonable design approach can be sought in the design of taller wood structures. The purpose of this technical paper is to compare various methods for calculating building deformations for wood-platform framed structures, which range from simply assuming each storey acts independent of the adjacent storey to a purely mechanics-based approach considering all 6 storeys acting as a continuous wall in order to compare the differences in drifts, stiffness, building period, base shear, and force distribution based on relative stiffness. General guidance is provided on which method to use.
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Controlled Rocking Cross-Laminated Timber Walls for Regions of Low-to-Moderate Seismicity

https://research.thinkwood.com/en/permalink/catalogue1726
Year of Publication
2016
Topic
Design and Systems
Seismic
Material
CLT (Cross-Laminated Timber)
Application
Walls
Author
Kovacs, Mike
Wiebe, Lydell
Year of Publication
2016
Format
Conference Paper
Material
CLT (Cross-Laminated Timber)
Application
Walls
Topic
Design and Systems
Seismic
Keywords
North America
Canada
Nonlinear Time History Analysis
Prototype
Controlled Rocking Heavy Timber Walls
Drifts
Energy Dissipation
Conference
World Conference on Timber Engineering
Research Status
Complete
Notes
August 22-25, 2016, Vienna, Austria p. 4671-4680
Summary
Controlled rocking heavy timber walls (CRHTW) were originally developed in New Zealand as a lowdamage seismic force resisting system using Laminated Veneer Lumber (LVL). This paper examines one way of adapting them to regions of low-to-moderate seismicity in North America, using Cross-Laminated Timber (CLT) composed of Canadian timber species. In particular, the adaptation simplifies the CRHTW by omitting supplemental energy dissipation and minimizing the potential for long-term damage to the timber from the post-tensioning. Key assumptions that are used in the design and analysis stages are evaluated with regard to the difference between timber products, and the structural performance of a prototype CRHTW design is confirmed by nonlinear time history analysis. Despite the lack of supplemental energy dissipation, the prototype design performs well with negligible residual drifts and a median peak roof drift of 0.63%. Future research is identified for the continued development of the adapted CRHTW.
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Cyclic Testing of Pre-engineered Beam-Hanger Connections & Reinforcement of Holes in Glulam Beams Using Self-tapping Screws

https://research.thinkwood.com/en/permalink/catalogue2518
Year of Publication
2020
Topic
Connections
Mechanical Properties
Application
Beams

Experimental Investigation of Self-Centering Cross Laminated Timber Walls

https://research.thinkwood.com/en/permalink/catalogue1654
Year of Publication
2016
Topic
Seismic
Mechanical Properties
Material
CLT (Cross-Laminated Timber)
Application
Walls
Author
Ganey, Ryan
Berman, Jeffrey
Yao, Lihong
Dolan, Daniel
Akbas, Tugce
Loftus, Sara
Sause, Richard
Ricles, James
Pei, Shiling
van de Lindt, John
Blomgren, Hans-Erik
Year of Publication
2016
Format
Conference Paper
Material
CLT (Cross-Laminated Timber)
Application
Walls
Topic
Seismic
Mechanical Properties
Keywords
Lateral Load Resisting System
Post-Tensioning
U-Shaped Flexural Plates
Limit States
Self-Centering
Strength
Stiffness
Interstory Drifts
Conference
World Conference on Timber Engineering
Research Status
Complete
Notes
August 22-25, 2016, Vienna, Austria p. 3547-3554
Summary
This paper describes experiments conducted to develop a resilient lateral force resisting wall system that combines cross-laminated timber (CLT) panels with vertical post-tensioning (PT) to provide post-event re-centering. Supplemental mild steel U-shaped flexural plate devices (UFPs) are intended to yield under cyclic loading while the PT and CLT components remain undamaged until large inter-story drifts are experienced by the wall. The experiments were designed to explore various limit states for self-centering CLT (SC-CLT) walls, including their dependence on design variables and their impact on performance, and to investigate strength and stiffness degradation at large interstory drifts. It was found that the SC-CLT walls were able to re-center even after large drift cycles and the crushing of the CLT material was the governing limit sate for most specimens. A hierarchy of desirable limit states was identified consisting of UFP yielding, CLT splitting, PT yielding, and CLT crushing.
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Linear Dynamic Analysis for Wood-Based Shear Walls and Podium Structures: Part 1: Developing Input Parameters for Linear Dynamic Analysis

https://research.thinkwood.com/en/permalink/catalogue740
Year of Publication
2013
Topic
Design and Systems
Mechanical Properties
Material
Light Frame (Lumber+Panels)
Application
Shear Walls
Author
Ni, Chun
Newfield, Grant
Wang, Jasmine
Organization
FPInnovations
Year of Publication
2013
Format
Report
Material
Light Frame (Lumber+Panels)
Application
Shear Walls
Topic
Design and Systems
Mechanical Properties
Keywords
Deflection
Linear Dynamic Analysis
National Building Code of Canada
Stiffness
Floor Drifts
Research Status
Complete
Summary
Utilizing Linear Dynamic Analysis (LDA) for designing steel and concrete structures has been common practice over the last 25 years. Once preliminary member sizes have been determined for either steel or concrete, building a model for LDA is generally easy as the member sizes and appropriate stiffness can be easily input into any analysis program. However, performing an LDA for a conventional wood-frame structure has been, until recently, essentially non-existent in practice. The biggest challenge is that the stiffness properties required to perform an LDA for a wood-based system are not as easily determined as they are for concrete or steel structures. This is mostly due to the complexities associated with determining the initial parameters required to perform the analysis. With the height limit for combustible construction limited to four stories under the National Building Code of Canada, it was uncommon for designers to perform detailed analysis to determine the stiffness of shear walls, distribution of forces, deflections, and inter-storey drifts. It was only in rare situations where one may have opted to check building deflections. With the recent change in allowable building heights for combustible buildings from four to six storeys under an amendment to the 2006 BC Building Code, it has become even more important that designers consider more sophisticated methods for the analysis and design of wood-based shear walls. As height limits increase, engineers should also be more concerned with the assumptions made in determining the relative stiffness of walls, distribution of forces, deflections, and inter-storey drifts to ensure that a building is properly detailed to meet the minimum Code objectives. Although the use of LDA has not been common practice, the more rigorous analysis, as demonstrated in the APEGBC bulletin on 5- and 6-storey wood-frame residential building projects (APEGBC 2011), could be considered the next step which allows one to perform an LDA. This fact sheet provides a method to assist designers who may want to consider an LDA for analyzing wood-frame structures. It is important to note that while LDA may provide useful information as well as streamline the design of wood-frame structures, it most often will not be necessary.
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Mitigating Torsional Irregularity using Cross Laminated Timber-Reinforced Concrete Hybrid System

https://research.thinkwood.com/en/permalink/catalogue1264
Year of Publication
2016
Topic
Design and Systems
Seismic
Material
CLT (Cross-Laminated Timber)
Application
Hybrid Building Systems
Author
Yazdinezhad, Mahdi
Organization
University of British Columbia
Year of Publication
2016
Format
Thesis
Material
CLT (Cross-Laminated Timber)
Application
Hybrid Building Systems
Topic
Design and Systems
Seismic
Keywords
Interstory Drifts
Reinforced Concrete
Linear Dynamic Analysis
Nonlinear Time History Analysis
Timber-Concrete Hybrid
Research Status
Complete
Summary
Seismic torsional responses in buildings is a result of eccentricity in mass and stiffness distribution. Torsional irregularity is one of the major causes of severe damage and collapse of structures during an earthquake. In this study, effect of torsion on the structures is reviewed, the definition of torsional irregularity and the characteristic of the structure that leads to this type of irregularity is elaborated. The evolution of the methods to consider the effect of torsion in the National Building Code of Canada (NBCC) is reviewed and different methods to prevent torsional irregularity in the structures are discussed. Hybridization with Cross-Laminated Timber (CLT) is suggested as a new method to rectify the effect of torsional irregularity for different performance levels. Accordingly, the definition of hybridization and hybrid structure seismic behavior, CLT material specifications and CLT seismic performance is discussed. In order to evaluate the effect of CLT hybridization on buildings with torsional irregularity, a four-storey reinforced concrete (RC) structure with torsional irregularity is considered for Vancouver seismicity condition. SAP2000 software is used to conduct Linear Dynamic Analysis (LDA) and Non-Linear Time History Analysis (NLTHA) using eight different ground motion scaled to Vancouver design spectra. The effect of the CLT wall panel as shear wall on the in plane seismic base shear and inter-storey drift is shown using the linear and non-linear dynamic analysis. The result from the analysis compared to the code static values. The literature of Performance Based Seismic Design (PBSD) is reviewed. PBSD is used to determine the performance level of the original and hybrid building. The inter-storey drifts criteria defined in FEMA 356 guidelines is used for the purpose of NLTHA.
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7 records – page 1 of 1.