Investigation of rolling shear properties of cross-laminated timber (CLT) and comparison of experimental approaches
https://www.sciencedirect.com/science/article/abs/... [Mechanical Performance] [Journal Article] 2022
Richard Nero, Philip Christopher, Tuan Ngo
The structural behaviour of a cross laminated timber (CLT) system is dictated in-part by the rolling shear properties (both strength fr and modulus Gr) of its laminates. To investigate the rolling shear properties of CLT, short-span four-point bending tests, modified planar shear (MPS) tests with timber sandwich plates, and MPS tests with steel sandwich plates were conducted on Australian grown Eucalyptus nitens and radiata pine, as well as European grown Norway spruce. A strong positive relatio...

Current Status of Hardwood Sawmills to Produce Structural Grade Hardwood Lumber
http://www.journalmtc.com/index.php/mtcj/article/v... [Raw Materials] [Journal Article] 2021
Adhikari, S., Quesada, H., Bond, B., & Hammett, T.
Hardwood lumber could be used in Cross-laminated timber (CLT) manufacturing for structural application if the lumber were produced to meet the minimum raw material requirements. However, hardwood sawmills do not currently produce lumber that satisfies CLT requirements, so it is necessary to determine if they have the ability and capacity to produce such lumber. Thus, the objective of this study was to measure the current capability of sawmills to produce structural grade hardwood lumber and, if ...

Structural Timber Design in Curricula of Canadian Universities: Current Status and Future Needs
https://www.mdpi.com/2227-7102/11/12/765... [Other] [Journal Article] 2021
Daneshvar, H.; Goni, T.; Zhang, S.; Kelterborn, R.; Chui, Y.H.
Due to the efficiency, sustainability, and advances in firefighting technologies, the allowable height for wood buildings was increased from 4 to 6 storeys in 2015 and will be further increased to 12 storeys in the 2020 edition of the National Building Code of Canada, as a result of the advent and application of mass timber products. To match the development in the industry and the increasing need in the market for highly skilled timber engineers, structural timber design curricula at the univer...

Wood and Engineered Wood Products: Stress and Deformation
https://www.intechopen.com/online-first/79485... [Mechanical Performance] [Book/Book Section] 2021
Meng Gong
Wood, as a natural, sustainable, and renewable bio-composite material, has a long history of serving humanity as construction materials. With the advance in technologies, many modern engineered wood products (EWPs) have been invented, produced, and used in construction, such as laminated veneer lumber, oriented strand board, and cross laminated timber. This chapter first introduces the classification, rationales, and pros and cons of EWPs. Secondly, it discusses the stress-related topics, includ...

Dowel-Bearing Strength of Southern Pine Cross-Laminated Timber
https://ascelibrary.org/doi/full/10.1061/%28ASCE%2... [Raw Materials] [Journal Article] 2022
Daniel P. Hindman, M.ASCE; Benjamin Richardson; and Achmaa Vaanjilnorov, A.M.ASCE
The current method for estimating parallel-to-grain dowel bearing strength of cross-laminated timber (CLT) fasteners applied perpendicular to the face in the US adjusts the length of the fastener to account for the effect of cross-layers rather than modifying the dowel bearing strength. This method is counter to more-commonly used methods in Canada and Europe which adjust the dowel bearing strength of the CLT material and using the original length of the dowel. Currently, there are no experiment...

Long-term bending properties of cross-laminated timber made from Japanese larch under constant environment
https://jwoodscience.springeropen.com/articles/10.... [Raw Materials] [Journal Article] 2021
Ryuya Takanashi, Yoshinori Ohashi, Wataru Ishihara, Kazushige Matsumoto
Cross-laminated timber (CLT) has been used extensively in timber construction. CLT panels are typically used in roofs and floors that carry a continuous load, and it is important to examine the long-term loading capacity of CLT. However, studies that focus on the long-term loading capacity of CLT are limited. To this end, we conducted long-term out-of-plane bending tests on seven-layer CLT made from Japanese larch (Larix kaempferi) under constant environmental conditions, investigated creep perf...

Full-Scale Cross-Laminated Timber Diaphragm Evaluation. II: CLT Diaphragm Connection Tests
https://ascelibrary.org/doi/full/10.1061/%28ASCE%2... [Seismic Performance] [Journal Article] 2022
Philip Line, Scott Nyseth, Ned Waltz
The objective of this study was to conduct tests on diaphragm connection configurations that either matched or were similar to those used in the full-scale diaphragm tests described in the Part 1 companion study (Line et al. 2022). The goal was to quantify their lateral load-deformation performance as an isolated assembly to assist in further understanding the measured full-scale diaphragm behavior. Diaphragm connection configurations tested include the custom steel tension strap, panel-to-beam ...

Full-Scale Cross-Laminated Timber Diaphragm Evaluation. I: Design and Full-Scale Diaphragm Testing
https://ascelibrary.org/doi/full/10.1061/%28ASCE%2... [Seismic Performance] [Journal Article] 2022
Philip Line, Scott Nyseth, Ned Waltz
The objective of this study was to monotonically test two 7.32×7.32-m (24×24-ft) cross-laminated timber (CLT) diaphragms designed using the provisions of ANSI/AWC 2021 (AWC. 2021. Special design provisions for wind and seismic. ANSI/AWC SDPWS-2021, Leesburg, VA: AWC). Each diaphragm used twelve 1.22×3.66-m (4×12-ft) CLT panels and plywood splines or glulam beams at panel shear connection locations. Diaphragms were tested in simple-span bending in general accordance with ASTM E455 (ASTM. 2017. St...

Structural fire engineering considerations for cross-laminated timber walls
https://www.sciencedirect.com/science/article/abs/... [Fire Performance] [Journal Article] 2022
Felix Wiesner, Rory Hadden, Susan Deeny, Luke Bisby
The current understanding of the thermo-mechanical response of cross-laminated timber (CLT) walls to fire is insufficiently developed. This paper presents results obtained using a novel experimental methodology on fire-exposed CLT walls under sustained loads. The findings demonstrate that global instability is likely to be the dominant failure mode for CLT walls in fire. Use of a polyurethane adhesive resulted in earlier structural failure than use of a melamine urea formaldehyde adhesive. Three...

Fire dynamics inside a large and open-plan compartment with exposed timber ceiling and columns: CodeRed #01
https://onlinelibrary.wiley.com/doi/full/10.1002/f... [Fire Performance] [Journal Article] 2022
Panagiotis Kotsovinos, Egle Rackauskaite, Eirik Christensen ,Adam Glew, Eoin O'Loughlin, Harry Mitchell, Rikesh Amin, Fabienne Robert, Mohammad Heidari, David Barber, Guillermo Rein, Judith Schulz
There is an increasing global demand to build from timber as it is a sustainable and attractive material. One of the key challenges associated with timber buildings is their performance in a fire, in particular, for medium- and high-rise buildings and when timber is exposed. Research on this topic to date has been performed in compartments smaller than 84 m2 which does not capture the fire dynamics of large compartments. This paper presents the first in a series of experiments carried out inside...

Determining elastic constants of full-size cross laminated timber panel supported on four nodes using a vibration method
https://www.sciencedirect.com/science/article/abs/... [Vibration/Acoustic Performance] [Journal Article] 2022

The objective of this study was to determine the elastic constants and fast identify the modal parameters of the first nine modes of full-size cross laminated timber (CLT) panel under four-node support using a vibration method. Firstly, the theoretical basis of vibration determination for elastic constants (modulus of elasticity in the length and width directions of the panel, Ex, Ey; in-plane shear modulus of the panel, Gxy) of full-size CLT panel under four sides completely free (FFFF) and fou...

Nonlinear SDOF Analytical Model of Mass-Timber Building with Post-Tensioned Rocking Walls
https://www.researchsquare.com/article/rs-1286955/... [Seismic Performance] [Journal Article] 2022
Angelo Aloisio, Marco Martino Rosso, Da Huang, Asif Iqbal, Massimo Fragiacomo, Shiling Pei
The dynamic response of post-tensioned rocking walls in a mass timber building can be reduced to a single-degree-of-freedom (SDOF) model. In this model, the rocking wall panel is simplied as a rigid block, while the base rotation represents the degree of freedom of the entire structure. The paper presents an analytical approach to develop and calibrate this nonlinear model using shake table tests of a full-scale two-story building with CLT rocking walls. The experimental data are used to estimat...

Nonlinear SDOF Analytical Model of Mass-Timber Building with Post-Tensioned Rocking Walls
https://www.researchsquare.com/article/rs-1286955/... [Seismic Performance] [Journal Article] 2022
ANGELO ALOISIO, Marco Martino Rosso, Da Huang, Asif Iqbal, Massimo Fragiacomo, Shiling Pei
This preprint is under consideration at Bulletin of Earthquake Engineering. A preprint is a preliminary version of amanuscript that has not completed peer review at a journal. We have improved readability, clarity, accessibility, and opportunities for engagement. Check out the new designRESEARCH ARTICLENonlinear SDOF Analytical Model of Mass-TimberBuilding with Post-Tensioned Rocking WallsANGELO ALOISIO, Marco Martino Rosso, Da Huang, Asif Iqbal, Massimo Fragiacomo, Shiling PeiDOI:10.21203/rs.3...

Parametric Optimization and Decision Support Model Framework for Life Cycle Cost Analysis and Life Cycle Assessment of Flexible Industrial Building Structures Integrating Production Planning
https://www.mdpi.com/2075-5309/12/2/162... [Environmental Performance] [Journal Article] 2022
Julia Reisinger, Stefan Kugler, Iva Kovacic, Maximilian Knoll
Most industrial buildings have a very short lifespan due to frequently changing production processes. The load-bearing structure severely limits the flexibility of industrial buildings and is a major contributor to their costs, carbon footprint and waste. This paper presents a parametric optimization and decision support (POD) model framework that enables automated structural analysis and simultaneous calculation of life cycle cost (LCC), life cycle assessment (LCA), recycling potential and flex...

Value-Based Conceptual Modeling of Costs and Embodied Carbon for Building Structural Systems: Mass Timber Perspective
https://digital.lib.washington.edu/researchworks/h... [Environmental Performance] [Thesis/Dissertation] 2021
Wiggins, Matthew James
Construction product manufacturing is a major contributor to the global climate change through its carbon emissions, known as embodied carbon (EC). In response, previous studies have found that utilizing a structural system of mass timber and cross laminated timber panels (CLT) can contribute to reduction of EC in the construction industry, when compared to other conventional structural systems. However, a major barrier that prevents the use of mass timber CLT is its higher cost than other avail...

Mechanical performance of glued-in rod glulam beam to column moment connection: An experimental study
https://www.sciencedirect.com/science/article/abs/... [Connectors] [Journal Article] 2022
Satheeskumar Navaratnam, Julian Thamboo, Thusiyanthan Ponnampalam, Srikanth Venkatesan, Kim Beng Chong
Engineered timber elements are gaining wide acceptance in construction with the increased practice of mass timber structures. The design of moment resistance connection is a contentious issue amongst practitioners and researchers. However, studies available on the performance of timber frame moment resisting connections made of various engineered timber sections are quite limited. This paper presents the outcome of a research study on the experimental assessment of the mechanical performance of ...

A new integrated approach on the seismic strengthening of existing RC buildings with external cross-laminated timber panels
https://cris.unibo.it/handle/11585/834371... [Seismic Performance] [Conference Paper] 2021
Lorenzo Badini; Stephan Ott; Patrik Aondio; Stefan Winter
In this study a timber-based integrated solution is presented to solve at once common issues affecting typical reinforced concrete (RC) existing buildings, such as seismic and energy performances, providing an eco-friendly alternative to steel external bracing systems. Cross-laminated timber (CLT) walls are provided perpendicularly to the external façades as strengthening elements while interposed CLT slabs are foreseen at each floor level to host new architectural units together with a new env...

FIRE RESISTANCE OF TIMBER STRUCTURES A report for the National Institute of Standards and Technology
https://www.nist.gov/system/files/documents/el/fir... [Fire Performance] [Report] 2014
Andrew Buchanan, 1Birgit Östman, 1S P Tratek, 1Andrea Sweden, 1Eth Frangi, 1 Zurich, 1 Switzerland,
Timber structures have experienced a renaissance during the recent few decades due to their environmental credentials, and societal goals striving for sustainable development with lower energy demands and less pollution in all sectors including the construction sector that stands for a major part of the overall community economy. However, the combustibility of timber still limits its use as a building material by restrictions in building regulations in most countries, especially for higher and l...

The Need For Common Terminology For Fire Safe Design Of Timber Structures
https://www.research-collection.ethz.ch/handle/20.... [Fire Performance] [Conference Paper] 2021
Schmid, Joachim; Barber, David; Brandon, Daniel; Werther, Norman
Timber buildings are becoming more prevalent globally and engineers and approval authorities look for suitable guidance to assist with construction. Researchers publish valuable papers on the fire safety of timber and its use for the built environment, that are being used by the engineering community at a fast pace. It has become clear to the authors that terminology specifically related to the fire safety of timber buildings is not always consistent between published research, available guidanc...

Diagonal laminated timber—Experimental, analytical, and numerical studies on the torsional stiffness
https://www.sciencedirect.com/science/article/abs/... [Alternative/Hybrid Configurations] [Journal Article] 2022
Matthias Arnold, Philipp Dietsch, Roland Maderebner, Stefan Winter
This paper deals with the development and implementation of diagonal laminated timber (DLT), a composite timber product, consisting of individual layers which are rotated to each other to a certain angle to increase its torsional stiffness. For the investigation we chose a specific DLT characterized by layers arranged at angles of ±45° respectively ±30° (±60°). The adjusted layup increases stiffness properties and provides ideal product properties for plates under biaxial bending. The load-beari...