Skip header and navigation

11 records – page 1 of 2.

Deflection test and modal analysis of lightweight timber floors

https://research.thinkwood.com/en/permalink/catalogue3051
Year of Publication
2021
Topic
Acoustics and Vibration
Mechanical Properties
Author
Zhao, Xinyue
Huang, Yujie
Fu, Haiyan
Wang, Yunlu
Wang, Zheng
Sayed, Usama
Organization
Nanjing Forestry University
Publisher
Elsevier
Year of Publication
2021
Format
Journal Article
Topic
Acoustics and Vibration
Mechanical Properties
Keywords
Lightweight Timber Structure Building
Floor Structure
Static Load Test
Test Mode
Calculation Mode
Building Comfort
Research Status
Complete
Series
Journal of Bioresources and Bioproducts
Summary
In order to meet the objective requirements of the safety and comfort of the modern lightweight timber floors, and strengthen the research on the coupling performance of the lightweight timber floors vibration characteristics and the building comfort, this article discusses the floor of a two-story prefabricated lightweight timber building demonstration house. In this paper, the floor structure of a two-story light-weight wooden house has been carried out on structural calculation modal and experimental modal, static uniform load and concentrated load deflection value testing. The evaluation of the deflection value of the floor structure, the mode shape, the coupling of the fundamental frequency mode parameters, and the vibration comfort were also studied. The results show that the fundamental frequency simulation value, one-way modal test value and two-way modal test value of the floor structure all meet the requirements of BS-6472 (BS6472-1:2008). That is, the floor structure is not lower than 8 Hz design requirements, and meets the frequency of BS-6472(BS6472-1:2008). The weighted root mean square acceleration is lower than the requirement of 0.45 m/s2; the first three natural frequencies of the floor structure calculated by the finite element simulation are 16.413, 31.847 and 48.921 Hz, and the fundamental frequency mode is the bending vibration in the length and width directions. The second order is the bending mode in the length direction, and the third order is the bending mode in the width direction. The fundamental frequency of the two-way modal test of the floor structure is the first-order bending mode in the X direction; and the second-order natural frequency is the second-order bending vibration shape in the X direction. when the uniform load is mainly the weight of floor own, the simulated maximum deflection value is 1.0658 mm; the simulation is performed according to the standard value of 0.566 kN/m for the uniform load of the floor design, and the simulation is the largest. The maximum deflection value of the simulated floor is 1.47383 mm at its midpoint, which meets the requirements of National Building Code of Canada-2015 (NBCC). The maximum deflection limit of the light wood structure floor system is lower than 3 m and the maximum deflection limit is 2 mm; the six deflection value test lines simulated under a concentrated load of 1 kN all present a parabolic distribution and are symmetrical. The above results has engineering application value for promoting the research on the vibration characteristics of the fabricated lightweight timber floors structure and its optimization design.
Online Access
Free
Resource Link
Less detail

Design Methods of Elements from Cross-Laminated Timber Subjected to Flexure

https://research.thinkwood.com/en/permalink/catalogue189
Year of Publication
2015
Topic
Design and Systems
Mechanical Properties
Material
CLT (Cross-Laminated Timber)
Author
Vilguts, Aivars
Serdjuks, Dmitrijs
Pakrastins, Leonids
Publisher
ScienceDirect
Year of Publication
2015
Format
Journal Article
Material
CLT (Cross-Laminated Timber)
Topic
Design and Systems
Mechanical Properties
Keywords
Finite Element Method (FEM)
Static Loading Test
Stress
Research Status
Complete
Series
Procedia Engineering
Summary
Design methods of cross-laminated timber elements subjected to bending is considered. The methods are based on LVS EN 1995–1–1. The presented methods were checked by the experiment and analytically. Two cross-laminated timber plates with the total thickness of 95 mm were tested under action of static load. The considered cross-laminated timber plates were analysed by FEM method, which is based on the using of computational program ANSYSv14. The comparison of stresses acting in the edge fibres of the plate and the maximum vertical displacements shows that the considered methods can be used for engineering calculations so as the difference between the experimentally and analytically obtained results does not exceed 20%.
Online Access
Free
Resource Link
Less detail

Dynamic and Static Lateral Load Tests on Full-Sized 3-Storey CLT Construction for Seismic Design

https://research.thinkwood.com/en/permalink/catalogue481
Year of Publication
2014
Topic
Seismic
Material
CLT (Cross-Laminated Timber)
Application
Wood Building Systems
Author
Tsuchimoto, Takahiro
Kawai, Naohito
Yasumura, Motoi
Miyake, Tatsuya
Isoda, Hiroshi
Tsuda, Chihiro
Miura, Sota
Murakami, Satoshi
Nakagawa, Takafumi
Year of Publication
2014
Format
Conference Paper
Material
CLT (Cross-Laminated Timber)
Application
Wood Building Systems
Topic
Seismic
Keywords
Shake Table Test
Lateral Load Test
Shear Displacement
Joint Deformation
Conference
World Conference on Timber Engineering
Research Status
Complete
Notes
August 10-14, 2014, Quebec City, Canada
Summary
The Japanese domestic forests have never been maintained enough, and it was a great fear that the multiple functions of the forest such as watershed conservation, the land conservation, and so on has been declined. The construction employing the cross laminates timber (CLT) panels was offered as a method of large scale building in domestic and foreign countries. However, the seismic design method of CLT panel construction has never completed. So, in order to consider the seismic design method, the shaking table tests and static lateral load tests were conducted to the modelized CLT panel construction.
Online Access
Free
Resource Link
Less detail

Experimental and numerical investigations of two-way LVL–concrete composite plates with various support conditions

https://research.thinkwood.com/en/permalink/catalogue3138
Year of Publication
2022
Topic
Mechanical Properties
Material
LVL (Laminated Veneer Lumber)
Timber-Concrete Composite
Application
Floors
Author
Jaaranen, Joonas
Fink, Gerhard
Organization
Aalto University
Publisher
Elsevier
Year of Publication
2022
Format
Journal Article
Material
LVL (Laminated Veneer Lumber)
Timber-Concrete Composite
Application
Floors
Topic
Mechanical Properties
Keywords
Two-way Plate
Experimental Modal Analysis
Static Load Test
Finite Element Modelling
Research Status
Complete
Series
Engineering Structures
Summary
Design of modern timber floors is often governed by the vibration serviceability requirements. One way to improve vibration serviceability is through the design of two-way floor systems. In this paper, the behaviour of two-way LVL–concrete composite plates and a plate strip is investigated experimentally, with an emphasis on the performance of proposed dovetail joint for connecting the adjacent LVL panels. The investigations consist of the experimental modal analysis and static load deformation tests, performed under multiple support conditions. The results show a significant two-way action, indicated by about 45% higher fundamental natural frequency when four edges are supported instead of two. The point load deflection in the centre of the plate was reduced of about 9%. Furthermore, a numerical model for two-way TCC plates was developed and results show a wide agreement with the experimental behaviour, except for discrepancies related to deflections on the plate edge. The results from the experimental and numerical investigations indicate that the dovetail joint can produce a stiff connection, such that the LVL layer could be regarded as continuous in the connected direction.
Online Access
Free
Resource Link
Less detail

The Experimental Study on Seismic Performance of Cross-Laminated-Timber Panel Construction

https://research.thinkwood.com/en/permalink/catalogue972
Year of Publication
2012
Topic
Seismic
Material
CLT (Cross-Laminated Timber)
Author
Suganumi, Naoto
Goto, Hiroshi
Yasumura, Motoi
Hamamoto, Takashi
Miyake, Tatsuya
Minoru, Okabe
Kaiko, Naoto
Nakagawa, Takafumi
Tsuda, Chihiro
Organization
Architectural Institute of Japan
Year of Publication
2012
Format
Journal Article
Material
CLT (Cross-Laminated Timber)
Topic
Seismic
Keywords
Static Loading Test
Shaking Table Test
Research Status
Complete
Summary
The wood engineering community has dedicated a significant amount of effort over the last decades to establish a reliable predictive model for the load-carrying capacity of timber connections under wood failure mechanisms. Test results from various sources (Foschi and Longworth 1975; Johnsson 2003; Quenneville and Mohammad 2000; Stahl et al. 2004; Zarnani and Quenneville 2012a) demonstrate that for multi-fastener connections, failure of wood can be the dominant mode. In existing wood strength prediction models for parallel to grain failure in timber connections using dowel-type fasteners, different methods consider the minimum, maximum or the summation of the tensile and shear capacities of the failed wood block planes. This results in disagreements between the experimental values and the predictions. It is postulated that these methods are not appropriate since the stiffness in the wood blocks adjacent to the tensile and shear planes differs and this leads to uneven load distribution amongst the resisting planes (Johnsson 2004; Zarnani and Quenneville 2012a). The present study focuses on the nailed connections. A closed-form analytical method to determine the load-carrying capacity of wood under parallel-to-grain loading in small dowel-type connections in timber products is thus proposed. The proposed stiffness-based model has already been verified in brittle and mixed failure modes of timber rivet connections (Zarnani and Quenneville 2013b).
Online Access
Free
Resource Link
Less detail

Factors that Affect Bolted Joints in Japanese Larch Glulam

https://research.thinkwood.com/en/permalink/catalogue1560
Year of Publication
2016
Topic
Connections
Mechanical Properties
Material
Glulam (Glue-Laminated Timber)
Author
Zhao, Rongjun
Wang, Zi
Ren, Haiqing
Zhou, Haibin
Xing, Xinting
Zhong, Yong
Year of Publication
2016
Format
Conference Paper
Material
Glulam (Glue-Laminated Timber)
Topic
Connections
Mechanical Properties
Keywords
Japanese Larch
Bolted Joints
Loading Test
China
Conference
World Conference on Timber Engineering
Research Status
Complete
Notes
August 22-25, 2016, Vienna, Austria p. 1458-1463
Summary
Japanese larch (Larix kaempferi) is an important species in China. The extensive use of Japanese larch can alleviate lumber shortage in China. Various grades of Japanese larch (Larix kaempferi) laminas were chosen to study the factors that affect the bolted joint performance. By comparing the loading test results with the required design values,it revealed that: (1) Bolt diameter affected the loading performance, then, bolt class, and the lamina grade was the least influential factor. (2) Japanese larch glulam can achieve the required designed value to be used as structural materials.
Online Access
Free
Resource Link
Less detail

Load Testing and Assessment of a Field Demonstration CLT Bridge

https://research.thinkwood.com/en/permalink/catalogue2570
Topic
Serviceability
Market and Adoption
Material
CLT (Cross-Laminated Timber)
Application
Bridges and Spans
Organization
South Dakota State University
Material
CLT (Cross-Laminated Timber)
Application
Bridges and Spans
Topic
Serviceability
Market and Adoption
Keywords
Field Measurements
Load Testing
Moisture Content
Visual Inspection
Long-term Performance
Research Status
In Progress
Notes
Project contact is Junwon Seo at South Dakota State University
Summary
Cross-Laminated Timber (CLT) has great potential to promote wood products markets in appropriate transportation structures, particularly bridges on low-volume roads such as rural or forest roads. The project’s goals are to perform field load testing and evaluation of a demonstration CLT bridge on the nation’s low-volume roads and evaluate its long-term performance under in-service loads and environmental exposure. The team will pursue these goals through the following research objectives: 1) Design the demonstration CLT bridge system with design details; 2) Fabricate the designed CLT bridge; 3) Install the fabricated CLT bridge on a roadway in Grand Portage National Monument with Western Wood Structures, Wheeler, Cook County in Minnesota and the National Park Service; and 4) Perform load testing to assess performance of the implemented bridge and monitor its moisture content and field performance through visual inspection for its long-term behavior evaluation.
Less detail

Performance and failure modes of mass timber buckling-restrained braces under cyclic loading

https://research.thinkwood.com/en/permalink/catalogue3159
Year of Publication
2022
Topic
Mechanical Properties
Author
Takeuchi, Toru
Terazawa, Yuki
Komuro, Shogo
Kurata, Takashi
Sitler, Ben
Organization
Tokyo Institute of Technology
Nippon Steel Engineering
Publisher
Elsevier
Year of Publication
2022
Format
Journal Article
Topic
Mechanical Properties
Keywords
Buckling-restrained Brace
Mass Timber
Cyclic Loading Test
Bulging
Design Criteria
Research Status
Complete
Series
Engineering Structures
Summary
Buckling-restrained braces with mass timber restrainers (MT-BRBs) have recently been investigated by several researchers. However, timber restrainers exhibit brittle failure modes and have lower stiffness and strength than their composite and steel counterparts. Previous experiments have demonstrated that timber restrainers are particularly susceptible to local bulging and that this is a brittle failure resulting in a near total loss of strength. Nevertheless, local bulging and global stability design methods have not yet been established for BRBs with timber restrainers. This paper presents cyclic loading tests of MT-BRBs featuring different bolted restrainer compositions, core plate clearances, reinforcing plate arrangements, connections and boundary conditions. These tests produced a variety of weak- and strong-axis bulging and global buckling failure modes. Design methods were developed to prevent each failure mode and then used to design full-scale MT-BRBs that were successfully tested and exhibited excellent performance.
Online Access
Free
Resource Link
Less detail

Structural Performance of Nail-Laminated Timber-Concrete Composite Floors

https://research.thinkwood.com/en/permalink/catalogue2146
Year of Publication
2017
Topic
Connections
Material
NLT (Nail-Laminated Timber)
Timber-Concrete Composite
Application
Floors
Author
Hong, Kwan Eui Marcel
Organization
University of British Columbia
Year of Publication
2017
Format
Thesis
Material
NLT (Nail-Laminated Timber)
Timber-Concrete Composite
Application
Floors
Topic
Connections
Keywords
Truss Plates
Self-Tapping Screws
Strength
Stiffness
Shear Connectors
Quasi-Static Loading Test
Bending
Research Status
Complete
Summary
Nail-laminated timber-concrete composite (TCC) is a system composed of a nail-laminated timber (NLT) panel connected to a concrete slab through shear connections. When used as flexural elements such as floors, the concrete and NLT are located in the compression and tension zones, respectively...
Online Access
Free
Resource Link
Less detail

Study on Seismic Performance of Building Structure with Cross Laminated Timber: Part 12: Objective and Loading Procedure and Accuracy of Static Loading Test

https://research.thinkwood.com/en/permalink/catalogue983
Year of Publication
2013
Topic
Seismic
Material
CLT (Cross-Laminated Timber)
Application
Wood Building Systems
Author
Kaiko, Naoto
Hamamoto, Takashi
Gosei, Murakami
Yahaura, Sota
Miyake, Tatsuya
Goto, Hiroshi
Nakagawa, Takafumi
Yasumura, Motoi
Organization
Architectural Institute of Japan
Year of Publication
2013
Format
Journal Article
Material
CLT (Cross-Laminated Timber)
Application
Wood Building Systems
Topic
Seismic
Keywords
Static Loading Test
Failure Behavior
Shear Force
Seismic Performance
Research Status
Complete
Summary
Cross-laminated timber (CLT) is a relatively new heavy timber construction material (also referred to as massive timber) that originated in central Europe and quickly spread to building applications around the world over the past two decades. Using dimension lumber (typically in the range of 1× or 2× sizes) glue laminated with each lamination layer oriented at 90° to the adjacent layer, CLT panels can be manufactured into virtually any size (with one dimension limited by the width of the press), precut and pregrooved into desirable shapes, and then shipped to the construction site for quick installation. Panelized CLT buildings are robust in resisting gravity load (compared to light-frame wood buildings) because CLT walls are effectively like solid wood pieces in load bearing. The design of CLT for gravity is relatively straightforward for residential and light commercial applications where there are plenty of wall lines in the floor plan. However, the behavior of panelized CLT systems under lateral load is not well understood especially when there is high seismic demand. Compared to light-frame wood shear walls, it is relatively difficult for panelized CLT shear walls to achieve similar levels of lateral deflection without paying special attention to design details, i.e., connections. A design lacking ductility or energy dissipating mechanism will result in high acceleration amplifications and excessive global overturning demands for multistory buildings, and even more so for tall wood buildings. Although a number of studies have been conducted on CLT shear walls and building assemblies since the 1990s, the wood design community’s understanding of the seismic behavior of panelized CLT systems is still in the learning phase, hence the impetus for this article and the tall CLT building workshop, which will be introduced herein. For example, there has been a recent trend in engineering to improve resiliency, which seeks to design a building system such that it can be restored to normal functionality sooner after an earthquake than previously possible, i.e., it is a resilient system. While various resilient lateral system concepts have been explored for concrete and steel construction, this concept has not yet been realized for multistory CLT systems. This forum article presents a review of past research developments on CLT as a lateral force-resisting system, the current trend toward design and construction of tall buildings with CLT worldwide, and attempts to summarize the societal needs and challenges in developing resilient CLT construction in regions of high seismicity in the United States.
Online Access
Free
Resource Link
Less detail

11 records – page 1 of 2.