Characteristics of Polyurethane Cross-Laminated Timber Made from a Combination of Pine and Coconut
https://sylvalestari.fp.unila.ac.id/index.php/JHT/... [Raw Materials] [Journal Article] 2023
Muhammad Iqbal Adi Baskara, Yusuf Sudo Hadi, Muhammad Adly Rahandi Lubis, Muhammad Iqbal Maulana, Rita Kartika Sari, Fauzi Febrianto, Wahyu Hidayat
The objective of this study was to assess the properties of cross-laminated timber (CLT) fabricated from the combination of Sumatran pine (P) and coconut trunk (C) bonded with polyurethane adhesive. The basic properties of raw materials and adhesives were characterized. The CLT panels’ length, width, and thickness are 100 cm by 30 cm by 3.6 cm, respectively. Three-layer CLT was made with 4 combinations of face/core/back lamina, i.e., PPP, CCC, PCP, and CPC, which are arranged perpendicular to ea...

A Solution Method for Creating Laminated Wood Panels with Revalorized Wood Boards
https://matheo.uliege.be/handle/2268.2/16974... [Raw Materials] [Thesis/Dissertation] 2023
Tanguy Spécia
The increasing demand for natural resources and the environmental commitments towards sustainable practices have led to a surge of interest in finding efficient solutions for the two-dimensional problem of creating laminated wood panels with revalorized wood boards. To address this challenge, sustainable and circular solutions are imperative. This thesis presents an exact solution to the problem, establishing its NP-hardness and justifying the need for an approximation method. This final solutio...

Fire spread in a large compartment with exposed cross-laminated timber and open ventilation conditions: #FRIC-01 – Exposed ceiling
https://www.sciencedirect.com/science/article/pii/... [Fire Performance] [Journal Article] 2023
Andreas Sæter Bøe, Kathinka Leikanger Friquin, Daniel Brandon, Anne Steen-Hansen, Ivar S. Ertesvåg
Exposing cross-laminated timber (CLT) structures in buildings is increasingly popular in modern buildings. However, large timber surfaces, window facades, and different geometries can change the fire dynamics in a compartment. The effect of those parameters, therefore, needs to be studied. Two large-scale CLT compartment fire experiments (95 m2) have consequently been performed. The experiments were designed to represent a modern office building with an open-plan space and large window openings....

Cross-Laminated Timber-Concrete Composite Floor Systems for Tall Building Design
https://ir.library.oregonstate.edu/concern/graduat... [Connectors] [Thesis/Dissertation] 2022
I. Morrell
With growing interest in mass timber, especially mass timber panels (MTP), there has been a need to better understand their structural properties. One of the most versatile uses for MTP are as floor systems. Under new code provisions, these floors can be utilized in new and taller building types, but will require a noncombustible topping, generally concrete.The first portion involved characterizing the withdrawal response of different Self-Tapping Screws (STS) at varying angles to grain in MTPs ...

Engineered Wood Products for Construction
https://www.intechopen.com/chapters/80719... [Commercial/Company Information] [Book/Book Section] 2022
Hüseyin Emre Ilgın, Markku Karjalainen, Olli-Paavo Koponen, Anu Soikkeli
Construction work is very resource-intensive, and construction projects contain many parameters, in which the choice of building material is one of the critical decisions with numerous criteria, e.g., cost, durability, and environmental impact. Moreover, this complex process includes different parties such as contractors, architects, engineers, where contractors are the most influential decision-makers in material selection. Increasing the use of renewable materials such as wood, which is a tech...

Lateral load capacity of WikiHouse composite walls from CNC cut timber panels
https://engrxiv.org/preprint/view/2266... [Mechanical Performance] [Report] 2022
G. Granello, T. Reynolds, R. Taleb, C. Prest
Computer-numerical-control (CNC) fabrication of interlocking-plate timber structures is a novel construction method that allows to build structural elements without mechanical fasteners: the load transfer mainly relies on direct contact and friction between the composing panels. In this work, the lateral load capacity of shear walls formed from interlocking CNC cut plywood elements is investigated by means of experimental testing and analytical modelling....

Life Cycle Analysis of Mass Timber and Reinforced Concrete Three-Story Structures
https://ir.library.oregonstate.edu/downloads/4b29b... [Environmental Performance] [Thesis/Dissertation] 2023
David Brown
With growing awareness of the negative impacts of the built environment, solutions for dramatic environmental, economic, and social improvements are sparking in all sectors, especially within the construction industry. The work of this thesis aims to quantify and compare social, economic, and environmental impacts of a three-story mass timber structure and a three-story reinforced concrete structure in the Pacific Northwest....

Evaluation of the Structural Performance of Shear Walls Built by Multi-layer Composite Laminated Panels
https://www.proceedings.com/069179-0332.html... [Connectors] [Thesis/Dissertation] 2023
Lin Zheng
Recently, the implementation of cross-laminated timber (CLT) in building systems has rapidly developed in many countries including Canada. Despite this, further improvement in the product performance of CLT is desirable. Composite Laminated Panels (CLP) have been developed due to the need to overcome one of the key weaknesses of traditional CLT, namely the rolling shear failure. CLP is made by combining traditional lumber with structural composite lumber (SCL). This thesis focuses on the structu...

Expanding the market of biomaterials
https://www.proquest.com/docview/2815137591?pq-ori... [Mechanical Performance] [Thesis/Dissertation] 2023
F. Quin Jr.
The objectives of this research will 1) evaluate the behavior of two single bolt connections in the post-to-rail joint in a hardwood stairway system; 2) the potential of post-treating pre-fabricated cross-laminated timber (CLT) panels with two different copper based preservative treatments; and 3) estimated design values for a commercially sourced bolt laminated bamboo industrial mat. To accomplish these objectives, this dissertation is divided into five sections: 1) Introduction, 2) Structural ...

Carbon Leadership Forum Material Baselines for North America
https://carbonleadershipforum.org/clf-material-bas... [Environmental Performance] [Report] 2023
Brook Waldman, Allison Hyatt, Stephanie Carlisle, Jordan Palmeri, Kathrina Simonen
The CLF Baseline values represent an estimate of industry-average GHG emissions for construction materials manufactured in North America. An overwhelming majority of the CLF Baselines published in this report are based on a North American industry-wide EPD if one was available at the time of publication. As such, it is appropriate to use this number as a rough estimate of a product type’s embodied carbon before a specific product has been selected or as a reference value against which product-le...

Development of predicting equations for slip modulus and shear capacity of CLT–concrete composite with screw connections
https://www.sciencedirect.com/science/article/abs/... [Connectors] [Journal Article] 2023
Gi Young Jeong, Van Sy Pham, Dang Khai Tran
This study investigated the effects of density, screw inclination angle, and screw arrangement on the slip modulus and shear capacity of a screw connection for a cross-laminated timber (CLT) concrete composite (CCC). A total of 35 push-out tests were conducted to investigate slip modulus and shear resistance of the CCC using a self-tapping screw. The test results identified double and single plastic hinges in the screw as the main failure mechanisms in the CLT–concrete screw connection. ...

Effect of Fibre Orientation on the Bond Properties of Softwood and Hardwood Interfaces
https://dro.deakin.edu.au/articles/journal_contrib... [Raw Materials] [Journal Article] 2023
Xin Li, Mahmud Ashraf, Bidur Kafle, Mahbube Subhani
Increasing concerns regarding carbon emissions and climate change are prompting a shift toward the use of sustainable materials in the construction industry. Engineered timber products are gaining attention in the construction industry due to advancements in lamination techniques and adhesives as well as the renewable characteristics of wood. Bond properties play a significant role in engineered timber products. In Australia, Radiata Pine (RP, softwood) and Shining Gum (SG, hardwood) share a lar...

Comparative study of greenhouse gas emission calculations and the environmental impact in the life cycle assessment of buildings in China, Finland, and the United States
https://www.sciencedirect.com/science/article/abs/... [Environmental Performance] [Journal Article] 2023
L. Shi, X. Qi, Z. Yang, L. Tao, Y. Li, J. Qiu, X. Jiang
Based on the life cycle assessment (LCA) theory, a comparative empirical analysis was conducted among residential and public building sets in China, Finland, and the United States considering the life-cycle GHG emissions, which demonstrated notable differences in the Product stage (A1–A3), Maintenance and material replacement stage (B1–B5), and Energy use stage (B6) between each building set. Different building retrofit scenarios were then established to study the emission reduction methods. The...

World Wood Day Online Symposium & The Fifth IUFRO Forest Products Culture Colloquium
http://www.worldwoodday.org/2023/regions_event/39... [General Information] [Conference Paper] 2023
Yan Xiao
Understanding wood as cultural heritage requires wood science and technology research into the material properties of these wood species (including non-wood counterparts), usually concerning their anatomical, physical and chemical characteristics in comparison with sound counterpart materials. Research also focuses on best material conservation/protection practices to enhance their service life (biological durability, abiotic durability). Furthermore, exploring the relationship between wood cult...

Feasibility of Underutilized West African Species in Cross-Laminated Timber Application
https://www.researchgate.net/publication/368789726... [Raw Materials] [Others] 2023
B.J. Ibitolu
In this study, the feasibility of the feasibility of underutilized West Africa Species for Cross Laminated Timber (CLT) Application were evaluated. Standards governing CLT in predominant places of use were elucidated with focus on CLT material property criteria. A review on some West African species with focus on their strength classification according to EN338. Two (2) underutilized specie Rhizophora racemosa (Igba) and Syzgium guineense (Adere) grown in Nigeria were accessed for minimum struct...

Numerical Investigation of the Axial Stress Distribution of Self-Tapping Screws in Mass Timber Products during Wetting or Drying
https://www.mdpi.com/2075-5309/13/3/623... [Moisture/Durability] [Journal Article] 2023
M.T. Khan, C. Ni, J. Wang, Y.H. Chui
Self-tapping screws (STS) are used in wood-to-wood and wood-to-steel connections in timber structures. Premature failure of STS during the construction phase has been reported by structural engineers and contractors in relation to a few North American mass-timber projects. This STS failure type is suspected of having been precipitated by additional axial stress exerted on STS from swelling of the wood resulting from prolonged wetting. This study investigates the axial stress distribution of STS ...

Finite Element Analysis of Glulam Beams with Transverse and Longitudinal Notches
https://www.proceedings.com/069179-0356.html... [Connectors] [Conference Paper] 2023
S. Malek, A. Goodarzi, R. Parra, P. Khoshkbari
Laminated wood composites, such as glued-laminated timber (Glulam) and cross-laminated Timber (CLT), are increasingly being used in the design of mass timber buildings. In solid timber (sawn lumber) and engineered wood products (EWPs), transverse notches are generally used at connections or at supports to reduce the height of beams. Small longitudinal notches may also be cut along beams and columns for aesthetic purposes. It is known that abrupt cross-section changes create stress concentrations...

Cyclic model of post-tensioned low damage timber walls with dissipative devices
https://www.sciencedirect.com/science/article/pii/... [Seismic Performance] [Journal Article] 2023
V. Tomei, M. Zucconi, B. Ferracuti
Post-tensioned rocking dissipative timber wall systems born from the idea to obtain structural solutions able to guarantee, after a seismic event, a rapid re-use of the buildings without permanent damage, as well as to guarantee the safeguarding of human life. In this framework, the rocking of timber walls is entrusted to post-tensioned bars, placed in ad hoc cavities of the panel, while the dissipative contribution is provided by steel dampers, which are sacrificial elements subjected to damage...

Experimental and numerical analysis of specimen configurations for Cross Laminated timber on rolling shear stiffness and strength response
https://www.sciencedirect.com/science/article/abs/... [Mechanical Performance] [Journal Article] 2023
João Vítor Felippe Silva, Marcos Cesar de Moraes Pereira, Maria Fernanda Felippe Silva, Julio Cesar Molina
This work aimed to perform the numerical and experimental analysis of three test setups (bending, vertical shear, and inclined shear) of CLT used to determine the rolling shear stiffness and strength. CLT specimens were manufactured with four different Brazilian wood species and two-component polyurethane adhesive. The stress distributions in the CLT test setups were simulated by Finite Element Method using ANSYS software. Rolling shear stiffness and strength was directly proportional to wood d...

Review of the charring rates of different timber species
https://onlinelibrary.wiley.com/doi/10.1002/fam.31... [Fire Performance] [Journal Article] 2023
Julie Liu, Erica C. Fischer
During a fire, the load-carrying cross section of timber members will reduce due to charring. This article summarizes experimental investigations into the charring rate of different timber species under standard fire conditions, identifies material properties that contribute to the variations of char rates across the different species, and evaluates the applicability of prescribed charring rates to solid timber, cross-laminated timber (CLT), and glulam exposed to standard fires....