Skip header and navigation

15 records – page 1 of 2.

Damage Assessment of Connections used in Cross-Laminated Timber Subject to Cyclic Loads

https://research.thinkwood.com/en/permalink/catalogue225
Year of Publication
2014
Topic
Connections
Seismic
Material
CLT (Cross-Laminated Timber)
Application
Shear Walls
Author
Schneider, Johannes
Karacabeyli, Erol
Popovski, Marjan
Stiemer, Siegfried
Tesfamariam, Solomon
Publisher
American Society of Civil Engineers
Year of Publication
2014
Format
Journal Article
Material
CLT (Cross-Laminated Timber)
Application
Shear Walls
Topic
Connections
Seismic
Keywords
Fasteners
Damage Index (DI) Method
Brackets
Load Displacement
Hysteretic
Research Status
Complete
Series
Journal of Performance of Constructed Facilities
Notes
https://doi.org/10.1061/(ASCE)CF.1943-5509.0000528
Summary
Cross-laminated timber (CLT) products are gaining popularity in the North American market and are being used in midrise wood buildings, in particular, in shearwall applications. Shearwalls provide resistance to lateral loads such as wind and earthquake loads, and therefore it is important to gain a better understanding of the behavior of CLT shearwall systems during earthquake events. This paper is focused on the seismic performance of connections between CLT shearwall panels and the foundation. CLT panels are very stiff and energy dissipation is accomplished by the connections. A literature review on previous research work related to damage prediction and assessment for wood frame structures was performed. Furthermore, a test program was conducted to investigate the performance of CLT connections subjected to simulated earthquake loads. Two different brackets in combination with five types of fasteners were tested under monotonic and cyclic loading protocols. In total, 98 connection tests were conducted and the monotonic load-displacement curves and hysteretic loops were obtained. In this paper, an energy-based cumulative damage assessment model was calibrated with the CLT connection test data. Finally, a correlation between the damage index and physical damage is provided.
Online Access
Free
Resource Link
Less detail

Damage Assessment of Cross Laminated Timber Connections Subjected to Simulated Earthquake Loads

https://research.thinkwood.com/en/permalink/catalogue70
Year of Publication
2012
Topic
Connections
Seismic
Material
CLT (Cross-Laminated Timber)
Application
Shear Walls
Author
Schneider, Johannes
Stiemer, Siegfried
Tesfamariam, Solomon
Karacabeyli, Erol
Popovski, Marjan
Year of Publication
2012
Format
Conference Paper
Material
CLT (Cross-Laminated Timber)
Application
Shear Walls
Topic
Connections
Seismic
Keywords
Damage
Panels
North American Market
Conference
World Conference on Timber Engineering
Research Status
Complete
Notes
July 15-19, 2012, Auckland, New Zealand
Summary
Wood-frame is the most common construction type for residential buildings in North America. However, there is a limit to the height of the building using a traditional wood-frame structure. Cross-laminated timber (CLT) provides possible solutions to mid-...
Online Access
Free
Resource Link
Less detail

Development of Steel-Wood Hybrid Systems for Buildings Under Dynamic Loads

https://research.thinkwood.com/en/permalink/catalogue845
Year of Publication
2012
Topic
Seismic
Design and Systems
Serviceability
Application
Hybrid Building Systems
Author
Stiemer, Siegfried
Tesfamariam, Solomon
Karacabeyli, Erol
Popovski, Marjan
Year of Publication
2012
Format
Conference Paper
Application
Hybrid Building Systems
Topic
Seismic
Design and Systems
Serviceability
Keywords
Dynamic Loads
Timber-Steel Hybrid
Strength
Conference
International Specialty Conference on Behaviour of Steel Structures in Seismic Areas
Research Status
Complete
Notes
January 9-11, 2012, Santiago, Chile
Summary
A steel-wood hybrid system furnishes not only aesthetically pleasing and sustainable hybrid structures but is superior in seismic applications due to the light weight, high resistance, and adjustable ductility. Such hybrid structural systems are not covered by any material and structural design standards that hinder the general implementation. For light structures, a builder’s guide to hybrid wood and steel connection details already exists in North America. Despite the obvious advantages, however, today’s applications of steel-wood hybrid structures have been limited. Rare hybrid buildings with a concentrically braced frame used for lateral load resistance with a glulam timber floor slab have been built as prototypes. The use of glulam floor slab led to a substantially reduced self-weight, compared with the reinforced concrete slab option. The lighter structure behaves superior in seismic events and has made wind loads the governing design case. The next generation steel-wood hybrid structures should optimally utilize each material. This paper describes a research program of the next generation wood-steel hybrid structures should optimally utilize each material. In detail the following development issues will be addressed: innovative hybrid steel-wood building systems, technical tools to predict structural responses of hybrid systems, design principles underpinning the definition of key code provisions related to strength and serviceability performance of hybrid buildings. It will be highlighted that potential structural problems at the design stage result from material incompatibilities. The constitutive properties of each material, hybrid-material, and joint properties reported in the literature will be used, or supplemented by findings from experimental work.
Online Access
Free
Resource Link
Less detail

Direct Displacement Based Design of A Novel Hybrid Structure: Steel Moment-Resisting Frames with Cross Laminated Timber Infill Walls

https://research.thinkwood.com/en/permalink/catalogue15
Year of Publication
2015
Topic
Design and Systems
Seismic
Material
CLT (Cross-Laminated Timber)
Application
Walls
Author
Bezabeh, Matiyas
Tesfamariam, Solomon
Stiemer, Siegfried
Popovski, Marjan
Karacabeyli, Erol
Publisher
Earthquake Engineering Research Institute
Year of Publication
2015
Format
Journal Article
Material
CLT (Cross-Laminated Timber)
Application
Walls
Topic
Design and Systems
Seismic
Keywords
Timber-Steel Hybrid
Panels
Nonlinear Time History Analysis
Research Status
Complete
Series
Earthquake Spectra
Summary
This study proposes an iterative direct displacement based design method for a novel steel-timber hybrid structure. The hybrid structure incorporates Cross Laminated Timber (CLT) shear panels as an infill in steel moment resisting frames. The proposed design method is applied to design 3-, 6-, and 9-story hybrid buildings with three bays and CLT infilled middle bay. Nonlinear time history analysis, using twenty earthquake ground motion records, is carried out to validate the performance of the design method. The results indicate that the proposed method effectively controls the displacements due to seismic excitation of the hybrid structure.
Online Access
Free
Resource Link
Less detail

Force Based Design Guideline for Timber-Steel Hybrid Structures: Steel Moment Resisting Frames with CLT Infill Walls

https://research.thinkwood.com/en/permalink/catalogue83
Year of Publication
2015
Topic
Design and Systems
Seismic
Material
CLT (Cross-Laminated Timber)
Application
Wood Building Systems
Author
Tesfamariam, Solomon
Stiemer, Siegfried
Bezabeh, Matiyas
Goertz, Caleb
Popovski, Marjan
Goda, Katsuichiro
Organization
University of British Columbia
Year of Publication
2015
Format
Report
Material
CLT (Cross-Laminated Timber)
Application
Wood Building Systems
Topic
Design and Systems
Seismic
Keywords
Overstrength
Ductility
National Building Code of Canada
Timber-Steel Hybrid
Office Buildings
Residential Buildings
Research Status
Complete
Summary
Provincial code changes have been made to allow construction of light wood-frame buildings up to 6 storeys in order to satisfy the urban housing demand in western Canadian cities. It started in 2009 when the BC Building Code was amended to increase the height limit for wood-frame structures from four to six. Recently, provinces of Quebec, Ontario and Alberta followed suit. While wood-frame construction is limited to six storeys, some innovative wood-hybrid systems can go to greater heights. In this report, a feasibility study of timber-based hybrid buildings is described as carried out by The University of British Columbia (UBC) in collaboration with FPInnovations. This project, funded through BC Forestry Innovation Investment's (FII) Wood First Program, had an objective to develop design guidelines for a new steel-timber hybrid structural system that can be used as part of the next generation "steel-timber hybrid structures" that is limited in scope to 20 storey office or residential buildings. ...
Online Access
Free
Resource Link
Less detail

On the Lateral Stability of Multi-Story Mass-Timber Buildings Subjected to Tornado-Like Wind Field

https://research.thinkwood.com/en/permalink/catalogue1972
Year of Publication
2018
Topic
Wind
Design and Systems
Material
CLT (Cross-Laminated Timber)
Application
Wood Building Systems
Author
Bezabeh, Matiyas
Gairola, Anant
Bitsuamlak, Girma
Tesfamariam, Solomon
Popovski, Marjan
Year of Publication
2018
Format
Conference Paper
Material
CLT (Cross-Laminated Timber)
Application
Wood Building Systems
Topic
Wind
Design and Systems
Keywords
Mass Timber
Lateral Load Resisting Systems
Tornadoes
Dynamic
Wind Loading
Lateral Instability
Enhanced Fujita
Boundary Layer Flow
Conference
World Conference on Timber Engineering
Research Status
Complete
Summary
In this paper, we examined the effects of extreme tornadic wind loads on mass-timber buildings. In general, mass-timber buildings utilize pre-engineered wood panels to form their main gravity and lateral load resisting systems. The lightweight nature of timber makes these types of emerging buildings lighter and more flexible than buildings made from concrete, masonry or steel. In general, global lateral instability of buildings can occur when the overturning forces due to wind loads exceed the dead load of the structures. In the present study, wind loads were obtained from laboratory simulations of tornado-like wind field and atmospheric boundary layer flow at Western University, Canada. Tornado wind loads from the laboratory tests were scaled to five Enhanced Fujita wind speeds representing various levels of damage. Dynamic structural analyses were carried out to assess floor level demands. It is shown that extreme tornado wind loads may pose significant damage to mass-timber buildings designed for 1-in-50 wind speed using a load factor of 1.4. Based on the obtained results, design strategies are suggested for mass-timber buildings in tornado-prone areas.
Online Access
Free
Resource Link
Less detail

Performance-Based Design of Tall Timber Buildings Under Earthquake and Wind Multi-Hazard Loads: Past, Present, and Future

https://research.thinkwood.com/en/permalink/catalogue2970
Year of Publication
2022
Topic
Design and Systems
Seismic
Application
Wood Building Systems
Author
Tesfamariam, Solomon
Organization
University of British Columbia
Editor
Kopp, Gregory
Publisher
Frontiers
Year of Publication
2022
Format
Journal Article
Application
Wood Building Systems
Topic
Design and Systems
Seismic
Keywords
Multi-hazard Design
Tall-timber building
Damping
Multi-fidelity Models
Energy Dissipation Devices
Optimization
Research Status
Complete
Series
Frontiers in Built Environment
Summary
The rapid growth of the urban population and associated environmental concerns are challenging city planners and developers to consider sustainable and cost-efficient building systems. Timber-based buildings, such as sustainable systems, are increasingly used. The timber buildings, however, being lighter and flexible, can be vulnerable to earthquakes and wind loads. This paper gives a state-of-the-art review on performance-based design (PBD) considerations and future direction for timber and timber-based hybrid buildings. The PBD review covered both earthquake and wind loads and multi-hazard design considerations. The review also provided 1) current practice and future direction in consideration of hazard, response, and loss assessment within the multi-hazard PBD, 2) damping and energy dissipation devices, 3) optimization under uncertainty, and 4) future of surrogate and multi-fidelity modeling in PBD.
Online Access
Free
Resource Link
Less detail

Performance of Semirigid Timber Frame with Lagscrewbolt Connections: Experimental, Analytical, and Numerical Model Results

https://research.thinkwood.com/en/permalink/catalogue201
Year of Publication
2015
Topic
Connections
Mechanical Properties
Material
Glulam (Glue-Laminated Timber)
Application
Beams
Author
Mori, Takuro
Nakatani, Makoto
Tesfamariam, Solomon
Publisher
Springer Berlin Heidelberg
Year of Publication
2015
Format
Journal Article
Material
Glulam (Glue-Laminated Timber)
Application
Beams
Topic
Connections
Mechanical Properties
Keywords
Lag Screws
Beam-to-Column
Moment Resistance
Stiffness
Finite Element Model
Analytical Model
Numerical Model
Research Status
Complete
Series
International Journal of Advanced Structural Engineering
Summary
This paper presents analytical and numerical models for semirigid timber frame with Lagscrewbolt (LSB) connections. A series of static and reverse cyclic experimental tests were carried out for different beam sizes (400, 500, and 600 mm depth) and column–base connections with different numbers of LSBs (4, 5, 8). For the beam–column connections, with increase in beam depth, moment resistance and stiffness values increased, and ductility factor reduced. For the column–base connection, with increase in the number of LSBs, the strength, stiffness, and ductility values increased. A material model available in OpenSees, Pinching4 hysteretic model, was calibrated for all connection test results. Finally, analytical model of the portal frame was developed and compared with the experimental test results. Overall, there was good agreement with the experimental test results, and the Pinching4 hysteretic model can readily be used for full-scale structural model.
Online Access
Free
Resource Link
Less detail

Risk-Based Wind Design of Tall Mass-Timber Buildings

https://research.thinkwood.com/en/permalink/catalogue1970
Year of Publication
2018
Topic
Wind
Material
CLT (Cross-Laminated Timber)
Glulam (Glue-Laminated Timber)
Application
Wood Building Systems
Author
Bezabeh, Matiyas
Tesfamariam, Solomon
Bitsuamlak, Girma
Year of Publication
2018
Format
Conference Paper
Material
CLT (Cross-Laminated Timber)
Glulam (Glue-Laminated Timber)
Application
Wood Building Systems
Topic
Wind
Keywords
Tall Wood
Tall Timber
Wind Loading
Fragility Curves
Dynamic Tests
Conference
The Canadian Society for Civil Engineers Annual Conference
Research Status
Complete
Summary
The rapid growth of urban population and the associated environmental concerns are partly influencing city planners and construction stakeholders to consider “Sustainable Urbanization” alternatives. In this regard, recent urban design strategies are entertaining the use of “tall timber buildings.” Generally, tall mass-timber buildings (MTBs) utilize pre-engineered wood panels to form their main gravity and lateral load resisting systems, which makes them lighter and more flexible than buildings made from concrete, masonry or steel. As a result, frequent exposure to excessive wind-induced vibrations can cause occupant discomfort and possible inhabitability of the buildings. This paper attempts to apply a risk-based procedure to design a 102-meter tall MTB by adapting and extending the Alan G. Davenport Wind Loading Chain as a probabilistic performance-based wind engineering framework. The structural systems of the study building are composed of Cross Laminated Timber (CLT) shear walls, CLT floors, glulam columns, and reinforced-concrete link beams. Initially, aerodynamic wind tunnel tests were carried out at the Boundary Layer Wind Tunnel Laboratory of Western University on the 1:200 scale MTB model to obtain transient wind loads. Subsequently, using the wind tunnel data, the study MTB was structurally designed. In the riskbased performance assessment, uncertainties were incorporated at each step of the Wind Loading Chain, i.e., local wind, exposure, aerodynamics, dynamic effects, and criteria. These uncertainties were explicitly modeled as random variables. Dynamic structural analyses were carried out in the frequency domain to include the amplification due to the resonance component of the excitation. Structural reliability analysis through Monte Carlo sampling was used to propagate the uncertainties through the Wind Loading Chain to quantify the risk of inhabitability and excessive deflection. The results of reliability analysis were used to develop fragility curves for wind vulnerability estimations. Based on the results, the effects of various uncertainties are discussed, and risk-based design decisions are forwarded.
Online Access
Free
Resource Link
Less detail

Seismic Base Shear Modification Factors for Timber-Steel Hybrid Structure: Collapse Risk Assessment Approach

https://research.thinkwood.com/en/permalink/catalogue1241
Year of Publication
2017
Topic
Seismic
Mechanical Properties
Material
CLT (Cross-Laminated Timber)
Application
Hybrid Building Systems
Author
Bezabeh, Matiyas
Tesfamariam, Solomon
Popovski, Marjan
Goda, Katsuichiro
Stiemer, Siegfried
Publisher
American Society of Civil Engineers
Year of Publication
2017
Format
Journal Article
Material
CLT (Cross-Laminated Timber)
Application
Hybrid Building Systems
Topic
Seismic
Mechanical Properties
Keywords
Canada
Timber-Steel Hybrid
Overstrength
Force Modification Factors
Collapse Risk Assessment Approach
Adjusted Collapse Margin Ratios
Research Status
Complete
Series
Journal of Structural Engineering
Summary
In this paper, to supplement the Canadian building code for a timber-steel hybrid structure, over-strength, and ductility-related force modification factors are developed and validated using a collapse risk assessment approach. The hybrid structure incorporates cross-laminated timber (CLT) infill walls within steel moment resisting frames. Following the FEMA P695 procedure, archetype buildings of 3-story, 6-story, and 9-story height with middle bay infilled with CLT were developed. Subsequently, a nonlinear static pushover analysis was performed to quantify the actual over-strength factors of the hybrid archetype buildings. To check the FEMA P695 acceptable collapse probabilities and adjusted collapse margin ratios (ACMRs), incremental dynamic analysis was carried out using 60 ground motion records that were selected to regional seismic hazard characteristics in southwestern British Columbia, Canada. Considering the total system uncertainty, comparison of the calculated ACMRs with the FEMA P695 requirement indicates the acceptability of the proposed over-strength and ductility factors
Online Access
Free
Resource Link
Less detail

15 records – page 1 of 2.