Skip header and navigation

Refine Results By

10 records – page 1 of 1.

Pinching Effect on Seismic Performance of a SDOF Lightframe Timber Structure

https://research.thinkwood.com/en/permalink/catalogue2542
Year of Publication
2021
Topic
Seismic
Material
CLT (Cross-Laminated Timber)
Light Frame (Lumber+Panels)
Application
Shear Walls
Author
Eini, Ariya
Zhou, Lina
Ni, Chun
Year of Publication
2021
Country of Publication
Canada
Format
Conference Paper
Material
CLT (Cross-Laminated Timber)
Light Frame (Lumber+Panels)
Application
Shear Walls
Topic
Seismic
Keywords
Pinching Behavior
Energy Dissipation
Hysteresis Loop
Light-frame wood
IDA Analysis
SDOF System
Language
English
Conference
World Conference on Timber Engineering
Research Status
Complete
Summary
Although energy dissipation is one of the key factors in resisting seismic force, current design codes only take into account the ductility of the backbone properties of hysteresis curves, and the energy dissipation is usually not accounted for. This paper focuses on understanding and assessing the influence of energy dissipation due to different pinching levels on the seismic performance of a light-frame wood shear wall system. Timber structures with identical backbone curves but different pinching levels were analyzed. Incremental dynamic analyses were run on a single-degreeof-freedom system with varying pinching stiffness and residual strength. The seismic evaluation is presented by the spectral accelerations causing failure of the structure and the hysteresis energy dissipation under a suite of 22 ground motions (2 components per motion) over a wide range of fundamental periods of typical timber structures. Results show that the effect of pinching on the seismic performance of timber structures is period-dependent. Short period structures are more sensitive to the pinching of hysteresis loops compared to long period structures. The residual strength of pinching loops has a greater influence on the seismic performance than the stiffness of the pinching loops. Hysteretic energy dissipation derived from standard reversed-cyclic tests can provide a better understanding on the seismic resistance of timber structures. However, the hysteretic energy under a seismic event at near-collapse stage neither agrees with quasistatic cyclic test’s energy dissipation nor is well correlated to the maximum seismic capacity of the structure.
Online Access
Free
Less detail

Analysis of Cost Comparison and Effects of Change Orders During Construction: Study of a Mass Timber and a Concrete Building Project

https://research.thinkwood.com/en/permalink/catalogue2730
Year of Publication
2021
Topic
Cost
Material
CLT (Cross-Laminated Timber)
Author
Ahmed, Shafayet
Arocho, Ingrid
Publisher
ScienceDirect
Year of Publication
2021
Format
Journal Article
Material
CLT (Cross-Laminated Timber)
Topic
Cost
Keywords
Concrete Building
Cost Assessment
Change Orders
Construction
Cost Comparative Analysis
Language
English
Research Status
Complete
Series
Journal of Building Engineering
Summary
In recent years, timber has been considered as an alternative source of building material because of its sustainability and design efficiency. However, the cost competitiveness of timber buildings is still under study due to the lack of available cost information. This paper presents a comprehensive cost comparative analysis of a mass timber building mainly developed with cross-laminated timber (CLT). The actual construction cost of the project is compared with the modeled cost of the same building designed as a concrete option. The result shows that the construction cost of timber building is 6.43% higher than the modeled concrete building. The study further investigated the change orders associated with the project and found that the total cost of change orders contributed 5.62% to the final construction cost of mass timber building. The study is helpful to provide insight into the construction cost of typical mass timber buildings. It also can be used as a guide for the project owners to make decisions regarding their initial investments on a mass timber project.
Online Access
Free
Resource Link
Less detail

Variations of Moisture Content in Manufacturing CLT-Concrete Composite Slab Using Wet Construction Method

https://research.thinkwood.com/en/permalink/catalogue2732
Year of Publication
2021
Topic
Moisture
Material
CLT (Cross-Laminated Timber)
Application
Hybrid Building Systems
Author
Song, Yo-Jin
Baek, Seong-Yeob
Lee, In-Hwan
Hong, Soon-Il
Publisher
North Carolina State University
Year of Publication
2021
Country of Publication
United States
Format
Journal Article
Material
CLT (Cross-Laminated Timber)
Application
Hybrid Building Systems
Topic
Moisture
Keywords
Wet Construction Method
Moisture Content
Teak
Composite
Adhesive
Delamination
Language
English
Research Status
Complete
Series
BioResources
Summary
Construction of eco-friendly high-rise buildings using cross-laminated timber (CLT)-concrete composite (CCC) slabs is increasing. CLT and concrete, which are major component materials of the CCC slab, are significantly affected by moisture. In particular, the moisture content of concrete in the production process affects the quality of both materials. In this study, the effects of the wet construction method on CLT and concrete component materials are examined by monitoring the behavior of the CCC slab during curing time (28 d) and by evaluating the quality of the concrete and CLT after curing. When manufacturing the CCC using the wet construction method, moisture penetration from the concrete into the CLT during the curing time is suppressed by the shear bonding between the concrete and the CLT when an adhesive is used. This minimizes the effect of the moisture on both component materials, consequently yielding uniform compressive strength to the concrete after curing and preventing the deterioration of the CLT’s delamination performance. Therefore, the shear bonding method using an adhesive is expected to minimize the quality deterioration observed in concrete and CLT after curing.
Online Access
Free
Resource Link
Less detail

Structural Performance of a Hybrid Timber Wall System for Emergency Housing Facilities

https://research.thinkwood.com/en/permalink/catalogue2745
Year of Publication
2021
Topic
Design and Systems
Seismic
Material
CLT (Cross-Laminated Timber)
Application
Walls
Hybrid Building Systems
Author
Casagrande, Daniele
Sinito, Ester
Izzi, Matteo
Pasetto, Gaia
Polastri, Andrea
Publisher
ScienceDirect
Year of Publication
2021
Format
Journal Article
Material
CLT (Cross-Laminated Timber)
Application
Walls
Hybrid Building Systems
Topic
Design and Systems
Seismic
Keywords
Prefabrication
Modular
Emergency Housing
Temporary Building
Hybrid Timber Frame
Seismic Behaviour
Language
English
Research Status
Complete
Series
Journal of Building Engineering
Summary
This paper presents an innovative and sustainable timber constructive system that could be used as an alternative to traditional emergency housing facilities. The system proposed in this study is composed of prefabricated modular elements that are characterized by limited weight and simple assembly procedures, which represent strategic advantages when it comes facing a strong environmental disaster (e.g. an earthquake). The complete dismantling of structural elements and foundations is granted thanks to specific details and an innovative connection system called X-Mini, capable of replacing traditional anchoring devices (i.e. hold downs and angle brackets) by resisting both shear and tension loads. This constructive system, denoted as Hybrid Timber Frame (HTF), takes advantage of the strong prefabrication, reduced weight of light-frame timber systems, and of the excellent strength properties of the Cross Laminated Timber (CLT) panels. Specifically, the solid-timber members typically used in the structural elements of light-frame systems are replaced by CLT linear elements. The results of experimental tests and numerical simulations are critically presented and discussed, giving a detailed insight into the performance of the HTF under seismic conditions.
Online Access
Free
Resource Link
Less detail

Hardwood CLT Program in Southern and Central Ontario

https://research.thinkwood.com/en/permalink/catalogue2762
Year of Publication
2021
Topic
Design and Systems
Cost
Material
CLT (Cross-Laminated Timber)
Author
Li, Xincheng
Publisher
University of Toronto
Year of Publication
2021
Country of Publication
Canada
Format
Thesis
Material
CLT (Cross-Laminated Timber)
Topic
Design and Systems
Cost
Keywords
Manufacturing
Hardwood
Language
English
Research Status
Complete
Summary
Cross-laminated timber (CLT) is a large prefabricated solid engineering plank made of multiple layers of planks glued together and it is primarily used in structures such as the floors, walls, and roofs of buildings. ANSI/APA PRG 320 is the world recognized CLT lumber production standard, and the main raw material of CLT has always been softwood rather than hardwood. However, the bending strength, compressive strength, and shear strength of hardwood CLT lumber are stronger than softwood CLT lumber. The large and underutilized hardwood resources in central and southern Ontario provide a huge resource advantage for the hardwood CLT project. This article uses the Cost-Benefit Assessments model to assess the feasibility of investing in hardwood CLT plants in central and southern Ontario. The results show that the payback period of the hardwood CLT factory is 5 years, and the rate of return on investment of 10 years, 15 years, and 20 years are all-around 11%. This study could strengthen investor confidence and it also identifies the direction for the development of hardwood CLT plants in central and southern Ontario.
Online Access
Free
Resource Link
Less detail

Cyclic Response of Insulated Steel Angle Brackets Used for Cross-Laminated Timber Connections

https://research.thinkwood.com/en/permalink/catalogue2765
Year of Publication
2021
Topic
Seismic
Acoustics and Vibration
Connections
Material
CLT (Cross-Laminated Timber)
Application
Walls
Floors
Author
Kržan, Meta
Azinovic, Boris
Publisher
Springer
Year of Publication
2021
Format
Journal Article
Material
CLT (Cross-Laminated Timber)
Application
Walls
Floors
Topic
Seismic
Acoustics and Vibration
Connections
Keywords
Angle Bracket
Sound Insulation
Insulation
Monotonic Test
Cyclic Tests
Wall-to-Floor
Stiffness
Load Bearing Capacity
Shear
Tensile
Language
English
Research Status
Complete
Series
European Journal of Wood and Wood Products
Summary
In cross-laminated timber (CLT) buildings, in order to reduce the disturbing transmission of sound over the flanking parts, special insulation layers are used between the CLT walls and slabs, together with insulated angle-bracket connections. However, the influence of such CLT connections and insulation layers on the seismic resistance of CLT structures has not yet been studied. In this paper, experimental investigation on CLT panels installed on insulation bedding and fastened to the CLT floor using an innovative, insulated, steel angle bracket, are presented. The novelty of the investigated angle-bracket connection is, in addition to the sound insulation, its resistance to both shear as well as uplift forces as it is intended to be used instead of traditional angle brackets and hold-down connections to simplify the construction. Therefore, monotonic and cyclic tests on the CLT wall-to-floor connections were performed in shear and tensile/compressive load direction. Specimens with and without insulation under the angle bracket and between the CLT panels were studied and compared. Tests of insulated specimens have proved that the insulation has a marginal influence on the load-bearing capacity; however, it significantly influences the stiffness characteristics. In general, the experiments have shown that the connection could also be used for seismic resistant CLT structures, although some minor improvements should be made.
Online Access
Free
Resource Link
Less detail

Nested Buildings: An Innovative Strategy for the Integrated Seismic and Energy Retrofit of Existing Masonry Buildings with CLT Panels

https://research.thinkwood.com/en/permalink/catalogue2770
Year of Publication
2021
Topic
Design and Systems
Seismic
Material
CLT (Cross-Laminated Timber)
Application
Hybrid Building Systems
Author
Valluzzi, Maria Rosa
Saler, Elisa
Vignato, Alberto
Salvalaggio, Matteo
Croatto, Giorgio
Dorigatti, Giorgia
Turrini, Umberto
Publisher
MDPI
Year of Publication
2021
Format
Journal Article
Material
CLT (Cross-Laminated Timber)
Application
Hybrid Building Systems
Topic
Design and Systems
Seismic
Keywords
Nested Buildings
Seismic Retrofitting
Energy Efficiency
Integrated Intervention
Built Heritage
Masonry Buildings
Panels
Hybrid Structures
Italy
Language
English
Research Status
Complete
Series
Sustainability
Summary
The Italian building heritage is aged and inadequate to the high-performance levels required nowadays in terms of energy efficiency and seismic response. Innovative techniques are generating a strong interest, especially in terms of multi-level approaches and solution optimizations. Among these, Nested Buildings, an integrated intervention approach which preserves the external existing structure and provides a new structural system inside, aim at improving both energy and structural performances. The research presented hereinafter focuses on the strengthening of unreinforced masonry (URM) buildings with cross-laminated timber (CLT) panels, thanks to their lightweight, high stiffness, and good hygrothermal characteristics. The improvement of the hygrothermal performance was investigated through a 2D-model analyzed in the dynamic regime, which showed a general decreasing in the overall thermal transmittance for the retrofitted configurations. Then, to evaluate the seismic behavior of the coupled system, a parametric linear static analysis was implemented for both in-plane and out-of-plane directions, considering various masonry types and connector spacings. Results showed the efficiency of the intervention to improve the in-plane response of walls, thus validating possible applications to existing URM buildings, where local overturning mechanisms are prevented by either sufficient construction details or specific solutions. View Full-Text
Online Access
Free
Resource Link
Less detail

Effects of Climate Change on the Moisture Performance of Tallwood Building Envelope

https://research.thinkwood.com/en/permalink/catalogue2771
Year of Publication
2021
Topic
Moisture
Material
CLT (Cross-Laminated Timber)
Application
Building Envelope
Walls
Author
Defo, Maurice
Lacasse, Michael
Publisher
MDPI
Year of Publication
2021
Format
Journal Article
Material
CLT (Cross-Laminated Timber)
Application
Building Envelope
Walls
Topic
Moisture
Keywords
Climate Change
Hygrothermal Simulations
Moisture Performance
Durability
Mold Growth Risk
Language
English
Research Status
Complete
Series
Buildings
Summary
The objective of this study was to assess the potential effects of climate change on the moisture performance and durability of massive timber walls on the basis of results derived from hygrothermal simulations. One-dimensional simulations were run using DELPHIN 5.9.4 for 31 consecutive years of the 15 realizations of the modeled historical (1986–2016) and future (2062–2092) climates of five cities located across Canada. For all cities, water penetration in the wall assembly was assumed to be 1% wind-driven rain, and the air changes per hour in the drainage cavity was assumed to be 10. The mold growth index on the outer layer of the cross-laminated timber panel was used to compare the moisture performance for the historical and future periods. The simulation results showed that the risk of mold growth would increase in all the cities considered. However, the relative change varied from city to city. In the cities of Ottawa, Calgary and Winnipeg, the relative change in the mold growth index was higher than in the cities of Vancouver and St. John’s. For Vancouver and St. John’s, and under the assumptions used for these simulations, the risk was already higher under the historical period. This means that the mass timber walls in these two cities could not withstand a water penetration rate of 1% wind-driven rain, as used in the simulations, with a drainage cavity of 19 mm and an air changes per hour value of 10. Additional wall designs will be explored in respect to the moisture performance, and the results of these studies will be reported in a future publication. View Full-Text
Online Access
Free
Resource Link
Less detail

Joint Professional Practice Guidelines: Encapsulated Mass Timber Construction up to 12 Storeys

https://research.thinkwood.com/en/permalink/catalogue2772
Edition
Version 1.0 March 30, 2021
Year of Publication
2021
Topic
Design and Systems
Material
CLT (Cross-Laminated Timber)
DLT (Dowel Laminated Timber)
NLT (Nail-Laminated Timber)
PSL (Parallel Strand Lumber)
LSL (Laminated Strand Lumber)
Glulam (Glue-Laminated Timber)
Application
Wood Building Systems
Organization
Architectural Institute of British Columbia (AIBC)
Engineers and Geoscientists British Columbia
Edition
Version 1.0 March 30, 2021
Year of Publication
2021
Country of Publication
Canada
Format
Book/Guide
Material
CLT (Cross-Laminated Timber)
DLT (Dowel Laminated Timber)
NLT (Nail-Laminated Timber)
PSL (Parallel Strand Lumber)
LSL (Laminated Strand Lumber)
Glulam (Glue-Laminated Timber)
Application
Wood Building Systems
Topic
Design and Systems
Keywords
Acoustics
Structural
Design
Building Enclosure
Architecture
Quality Assurance
Building Code
Encapsulated Mass Timber Construction
Engineering
Fire Protection
Language
English
Research Status
Complete
Summary
These Joint Professional Practice Guidelines – Encapsulated Mass Timber Construction Up to 12 Storeys were jointly prepared by the Architectural Institute of British Columbia (AIBC) and Engineers and Geoscientists British Columbia. The AIBC and Engineers and Geoscientists BC regulate and govern the professions of architecture, engineering, and geoscience under the Architects Act and the Professional Governance Act. The AIBC and Engineers and Geoscientists BC each have a regulatory mandate to protect the public interest, which is met in part by setting and maintaining appropriate academic, experience, and professional practice standards. Engineering Professionals are required per Section 7.3.1 of the Bylaws - Professional Governance Act to have regard for applicable standards, policies, plans, and practices established by the government or by Engineers and Geoscientists BC, including professional practice guidelines. For Engineering Professionals, these professional practice guidelines clarify the expectations for professional practice, conduct, and competence when providing engineering services for EMTC buildings. For Architects, these guidelines provide important information and identify issues to be considered when providing architectural services for EMTC buildings. These guidelines deal with the performance of specific activities in a manner such that Architects and Engineering Professionals can meet their professional obligations under the Architects Act and the Professional Governance Act. These guidelines were developed in response to new classifications of building size and construction relative to occupancy introduced in the 2018 British Columbia Building Code (BCBC), under Division B, Article 3.2.2.48EMTC. Group C, up to 12 storeys, Sprinklered, and Article 3.2.2.57EMTC. Group D, up to 12 storeys, Sprinklered. These new classifications were introduced in Revision 2 of the 2018 BCBC on December 12, 2019 and in Amendment 12715 of the 2019 Vancouver Building By-law (VBBL) on July 1, 2020. Additionally, provisions related to Encapsulated Mass Timber Construction (EMTC) were introduced in Revision 1 of the 2018 British Columbia Fire Code (BCFC) on December 12, 2019. These guidelines were first published in 2021 to provide guidance on architectural and engineering considerations relating to these significant changes to the 2018 BCBC, the 2019 VBBL, and the 2018 BCFC. For Engineering Professionals, these guidelines are intended to clarify the expectations of professional practice, conduct, and competence when Engineering Professionals are engaged on an EMTC building. For Architects, these guidelines inform and support relevant competency standards of practice to be met when Architects are engaged on an EMTC building. As with all building and construction types, the EMTC-specific code provisions prescribe minimum requirements that must be met. The majority of EMTC of 7 to 12 storeys are considered High Buildings, and as such are subject to the BCBC, Subsection 3.2.6. Additional Requirements for High Buildings.
Online Access
Free
Resource Link
Less detail

A framework to Automate the Design of Digitally-Fabricated Timber Plate Structures

https://research.thinkwood.com/en/permalink/catalogue2773
Year of Publication
2021
Topic
Design and Systems
Application
Shell Structures
Author
Rad, Aryan Rezaei
Burton, Henry
Rogeau, Nicolas
Vestartas, Petras
Weinand, Yves
Publisher
Elsevier
Year of Publication
2021
Format
Journal Article
Application
Shell Structures
Topic
Design and Systems
Keywords
Connections
Timber Plates
CAD
CAE
Computer Programming
Macro Modeling Technique
Language
English
Research Status
Complete
Series
Computers & Structures
Summary
The current study uses knowledge from digital architecture, computer science, engineering informatics, and structural engineering to formulate an algorithmic framework for integrated Computer-Aided Design (CAD) and Computer-Aided Engineering (CAE) of Integrally-Attached Timber Plate (IATP) structures. The algorithm is designed to take the CAD 3D geometry of an IATP structure as input and automates the construction and analysis of the corresponding CAE model using a macroscopic element, which is an alternative to continuum Finite Element (FE) models. Each component of the macro model is assigned a unique tag that is linked to the relevant geometric and structural parameters. The CAE model integrity is maintained through the use of the common data model (CDM) concept and object-oriented programming. The relevant algorithms are implemented in Rhinoceros 3D using RhinoCommon, a .NET software development kit. Once the CAE macro model is generated, it is introduced to the OpenSees computational platform for structural analysis. The algorithmic framework is demonstrated using two case structures: a prefabricated timber beam with standard geometry and a free-form timber plate arch. The results are verified with measurements from physical experiments and FE models, where the time needed to convert thousands of CAD assemblies to the corresponding CAE models for response simulation is considerably reduced.
Online Access
Free
Resource Link
Less detail

10 records – page 1 of 1.