Hardwood CLT Program in Southern and Central Ontario
https://tspace.library.utoronto.ca/handle/1807/104... [Markets] [Thesis/Dissertation] 2021
Xincheng Li
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 lumb...

Hardwood CLT Program in Southern and Central Ontario
https://tspace.library.utoronto.ca/bitstream/1807/... [Markets] [Thesis/Dissertation] 2021
Xincheng Li
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 lumb...

Experimental and numerical analysis of residual load-carrying capacity of cross-laminated timber walls after fire
https://www.sciencedirect.com/science/article/abs/... [Fire Performance] [Journal Article] 2021
Yu Bai, Jin Zhang, Hao Shen
Cross-laminated timber (CLT) panels are widely used as structural members applied in a range of modern timber buildings. Changes in the load-carrying capacity of CLT walls after exposure to fire need to be discussed and summarized, but few studies have considered this due to a lack of available measurements and the prohibitive cost of performing the relevant experiments. To investigate the residual load-carrying capacity of CLT walls after fire, the multiple tests including axial compression tes...

Experimental testing of high capacity screwed connections in Douglas-fir CLT
https://www.nzffa.org.nz/farm-forestry-model/resou... [Connectors] [Report] 2021
Thomas Wright, Minghao Li
This report presents experimental results of high capacity hold-down connections in Douglas-fir Cross Laminated Timber (CLT) using self-tapping screws installed with mixed angles (inclined and 90° angle to the timber surface)....

Effects of knot area ratio on the bending properties of cross-laminated timber made from Korean pine
https://link.springer.com/article/10.1007/s00226-0... [Raw Materials] [Journal Article] 2021
Sung-Jun Pang, Kug-Bo Shim, Keon-Ho Kim
The effect of knot clusters on the bending properties of Korean pine (Pinus koraiensis) cross-laminated timber (CLT) was analyzed to increase the utilization of low-quality lumber. The laminae used to manufacture the CLT were classified into five groups, four major layer groups, and one minor layer group, by mechanical grade and knot area ratio (KAR) of the lamina. Out-of-plane bending tests were conducted on CLT made from each layer group. The modulus of elasticity (MOE) of the manufactured CLT...

Experimental Cyclic Test of Reduced Damage Detailed Drywall Partition Walls Integrated with a Timber Rocking Wall
https://www.tandfonline.com/doi/abs/10.1080/136324... [Seismic Performance] [Journal Article] 2021
Hamed Hasani, Keri L. Ryan
Bidirectional quasi-static cyclic loading was applied to a subassembly of drywall partition walls integrated with cross-laminated timber rocking walls. Details aimed to reduce seismic damage to the partition walls were investigated, such as slip connections of partition walls to the diaphragm and gap detailing for the wall intersections. Telescoping detailing eliminated damage to the framing at the wall ends compared to traditional slip-track detailing. The distributed gap wall delayed the damag...

Influence of the rocking behavior of shearwalls on the fundamental period of CLT structures
https://onlinelibrary.wiley.com/doi/full/10.1002/e... [Seismic Performance] [Journal Article] 2021
Daniele Casagrande, Stefano Pacchioli, Andrea Polastri, Luca Pozza
The comparison of results obtained from on-site modal tests and numerical analyses presented in recent studies showed that Cross Laminated Timber (CLT) buildings may exhibit a significant shift of fundamental period from the condition when rocking does not occur to the condition which the shearwall rocking is activated for. The objective of the current study is to establish a relationship between the fundamental period of CLT structures and the lateral drift of their global dynamic response. The...

Three-Dimensional Numerical Calculation Model for Static Behavior Simulation of Cross-Laminated Timber Plates under Thermal Environment
https://www.hindawi.com/journals/mpe/2021/1538928... [Moisture/Durability] [Journal Article] 2021
Wenliang Hu, Wei Hou, Zhao Zhu, Xuhui Huang
Cross-laminated timber (CLT) is well known as an interesting technical and economical product for modern wood structures. The use of CLT for modern construction industry has become increasingly popular in particular for residential timber buildings. Analyzing the CLT behavior in high thermal environment has attracted scholars’ attention. Thermal environment greatly influences the CLT properties and load bearing capacity of CLT, and the investigation can form the basis for predicting the structur...

Renovation of timber floors with structural glass: Structural and environmental performance
https://www.sciencedirect.com/science/article/abs/... [Alternative/Hybrid Configurations] [Journal Article] 2021
Žiga Unuk, Iva Lukić, Vesna Žegarac Leskovar, MiroslavPremrov
A common occurrence in building renovation is the modification in the usage category that can lead to higher imposed loads, and consequently the need for structural improvements to the existing structure or to a structural element, such as timber floors. Strengthening practices oftentimes affect the originality of the building or a structural element under consideration. However, the preservation of the originality of timber floors having historical, architectural and cultural interest can be of...

Doweled cross laminated timber: Experimental and analytical study
https://www.sciencedirect.com/science/article/abs/... [Alternative/Hybrid Configurations] [Journal Article] 2021
Marcos Cesar de Moraes Pereira, Luc ArthurPascal Sohier, Thierry Descamps, Carlito Calil Junior
In developed countries, the construction sector has moved towards industrialization and sustainability of construction and structural materials, thus solid wood construction has gained recognition. New products such as CLT panels are used for construction of multi-storey building, and other products that use the same principle of cross lamination have gained ground, as for instance the dowel cross laminated timber panel, called DCLT. This study aims to evaluate the structural behaviour of DCLT p...

Lateral Load Testing of a Full-Scale Cross-Laminated Timber Diaphragm
https://ascelibrary.org/doi/full/10.1061/%28ASCE%2... [Seismic Performance] [Journal Article] 2021
Anirudh Kode, M. Omar Amini, John W. van de Lindt, Philip Line,
Despite being introduced in Europe nearly 20  years ago, cross-laminated timber (CLT) is still not widely used in North America, and it has only recently garnered attention as a new construction material in the US. One primary reason for this is because of a lack design procedures for CLT as a lateral force resisting system for seismically active regions of the US. A CLT subassembly that has not been fully investigated is a horizontal diaphragm for floors, roofs, or bridge decks. The purpose of ...

Out-Of-Plane Constitutive Model to Capture the Tsunami-Load Response of Cross Laminated Timber Buildings
https://www.utoledo.edu/engineering/faculty/serhan... [Other] [Conference Paper] 2020
R. A. Salgado, S. Guner
Cross Laminated Timber (CLT) is a new and robust construction material that has gained increasing popularity as an alternative to create the resilient cities of the future. The response of CLT buildings under earthquake conditions has been widely investigated and shown to be favorable. To create disaster-resilient communities, new building systems must be able to withstand not only earthquakes but also subsequent tsunami events. Despite the good seismic performance of CLT buildings, their perf...

Developing a BIM and Simulation-Based Hazard Assessment and Visualization Framework for CLT Construction Design
https://ascelibrary.org/doi/full/10.1061/%28ASCE%2... [Connectors] [Journal Article] 2021
Samer BuHamdan, Tsvetomila Duncheva, Aladdin Alwisy
One emerging trend in sustainable medium-density construction is the use of mass timber products such as cross laminated timber (CLT), which is a novel approach that involves numerous connectors. Researchers have not previously investigated the potential health impacts of different connectors. This paper proposes a framework to correlate the specification of CLT connectors to the potential risk of exposure to hand arm vibration syndrome (HAVS). We also propose an innovative adaptation of the Loc...

Mechanical performances of finger jointed cross laminated timber (CLT)
https://link.springer.com/article/10.1007/s00107-0... [Raw Materials] [Journal Article] 2021
Kohei Komatsu, Makoto Nakatani, Toru Nakahara, Kenji Komatsu, Yasunobu Noda
Based on the idea of first producing small-size CLT panels and afterward connecting them using finger joints to make larger CLT panels, finger-jointed CLT test specimens were fabricated by setting experimental parameters such as the kind of finger joint (large or normal), the combination of finger joint strength (strong–strong, or weak–weak) and the number of layers, and ply (3L3P, 5L5P, and 5L7P). Destructive tests subjected to out-of-plane as well as in-plane bending and shear, and axial compr...

Preliminary evaluation of a density-based lumber grading method for hem-fir CLT manufacturing
https://link.springer.com/article/10.1007/s00107-0... [Other] [Journal Article] 2021
Hao Li, Libin Wang, Brad Jianhe Wang, Peixing Wei, Wentao Yu, Zhongqiang Fan, Guanben Du
In the manufacturing process of cross-laminated timber (CLT), lumber selection and grading are essential steps for the quality control of CLT. In this work, a density-based lumber grading method was preliminarily evaluated for hem-fir CLT manufacturing. Based on the univariate regression model of hem-fir lumber modulus of elasticity (MOE) and its density, a density-based grading model was developed. To identify the effectiveness of the model, 470 pieces of thin hem-fir lumber, were segregated in...

Charring of Timber–Determination of The Residual Virgin Cross Section and Charring Rates
https://www.researchgate.net/publication/348389904... [Fire Performance] [Conference Paper] 2020
Schmid, J., Klippel, M., Viertel, M., Presl, R., Fahrni, R., Totaro, A., & Frangi, A.
For the assessment of the fire resistance of timber members, the virgin wood has to be documented for a proper evaluation of any fire test result. However, actual fire resistance standards disregard the need to document the virgin cross-section. Numerous ad-hoc methods appeared around the world in labs and research facilities comprising a variety of methods from single ruler measurements to the determination of the virgin cross-section with temperature measurements. Especially for plane members ...

Dynamic Carbon Life Cycle and Energy Analysis for Cross-Laminated Timber in the Southeastern US
https://iopscience.iop.org/article/10.1088/1748-93... [Environmental Performance] [Journal Article] 2020
Kai Lan, Stephen S Kelley, Prakash Nepal, Yuan Yao
Life cycle assessment (LCA) has been used to understand the carbon and energy implications of manufacturing and using cross-laminated timber (CLT), an emerging and sustainable alternative to concrete and steel. However, previous LCAs of CLT are static analyses without considering the complex interactions between the CLT manufacturing and forest systems, which are dynamic and largely affected by the variations in forest management, CLT manufacturing, and end-of-life options. This study fills this...

Pull-out Behaviour of Axially Loaded Screwed-in Threaded Rods Embedded in CLT Elements: Experimental Study
https://www.researchgate.net/publication/351118587... [Connectors] [Journal Article] 2021
Huifeng Yang, Junfeng Ji, Haotian Tao, Benkai Shi
Experimental investigation on the pull-out behaviour, including the withdrawal capacity, slip stiffness and inter-facial shear stress, of axially loaded screwed-in threaded rod embedded in cross laminated timber (CLT) was conducted. Specimens with varying embedment length and different number of threaded rods were tested in this study. To prevent premature splitting failure of timber, some specimens were reinforced in the direction perpendicular to the timber grain with self-tapping screws. Test...

Predicting Nail Withdrawal Resistance and Bearing Strength of Cross-laminated Timbers from Mixed Species
https://ojs.cnr.ncsu.edu/index.php/BioRes/article/... [Connectors] [Journal Article] 2021
Keonho Kim
The increasing demand for sustainable architecture has led to a growing interest in wood structures. Hence, ensuring their structural stability and strength performance is an imperative. This study investigated the nail bearing strength and withdrawal resistance of mixed cross-laminated timber (CLT) using Japanese larch and yellow poplar layers. The mixed CLT was composed of three larch laminas (major) and two yellow poplar laminas (minor). The bearing strength of the mixed CLT decreased as the ...

An Experimental and Analytical Study on Cross-Laminated Bamboo Rocking Walls with Friction Dampers
https://www.techscience.com/jrm/v9n10/42554... [Raw Materials] [Journal Article] 2021
Qingfang Lv, Tongchen Han, Ye Liu, Yi Ding, Yujie Lu
Cross-laminated bamboo (CLB) have a high strength to weight ratio and stable bidirectional mechanical properties. Inspired by the investigation on cross-laminated timber (CLT) rocking walls, CLB rocking walls with conventional friction dampers (CFDs) are studied in this paper. To investigate the mechanical properties of the CLB rocking wall, seven tests are conducted under a cyclic loading scheme, and different test parameters, including the existence of the CFDs, the moment ratio, and the loadi...