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18 records – page 1 of 2.

100-Year Performance of Timber-Concrete Composite Bridges in the United States

https://research.thinkwood.com/en/permalink/catalogue2561
Year of Publication
2020
Topic
Serviceability
Application
Bridges and Spans
Author
Wacker, James
Dias, Alfredo
Hosteng, Travis
Year of Publication
2020
Country of Publication
United States
Format
Journal Article
Application
Bridges and Spans
Topic
Serviceability
Keywords
Concrete
Composite
Superstructure
Performance
Inspection
Language
English
Research Status
Complete
Series
Journal of Bridge Engineering
Summary
The use of timber–concrete composite (TCC) bridges in the United States dates back to approximately 1924 when the first bridge was constructed. Since then a large number of bridges have been built, of which more than 1,400 remain in service. The oldest bridges still in service are now more than 84 years old and predominately consist of two different TCC systems. The first system is a slab-type system that includes a longitudinal nail-laminated deck composite with a concrete deck top layer. The second system is a stringer system that includes either sawn timber or glulam stringers supporting a concrete deck top layer. The records indicate that most of the TCC highway bridges were constructed during the period of 1930–1960. The study presented in this paper discusses the experience and per-formance of these bridge systems in the US. The analysis is based on a review of the relevant literature and databases complemented with field inspections conducted within various research projects. Along with this review, a historical overview of the codes and guidelines available for the design of TCC bridges in the US is also included. The analysis undertaken showed that TCC bridges are an effective and durable design alternative for highway bridges once they have shown a high performance level, in some situations after more than 80 years in service with a low maintenance level.
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An Exploratory Study of Composite Cross-Laminated Timber (CCLT) Made from Bamboo and Hemlock-fir Mix

https://research.thinkwood.com/en/permalink/catalogue2411
Year of Publication
2019
Topic
Design and Systems
Material
CLT (Cross-Laminated Timber)
PSL (Parallel Strand Lumber)
Application
Wood Building Systems

Assessing the Complexity of Timber Gridshells in Architecture through Shape, Structure, and Material Classification

https://research.thinkwood.com/en/permalink/catalogue1876
Year of Publication
2019
Topic
Design and Systems
Application
Shell Structures

Connection Details Between Composite Beam and Cross-Laminated Timber Slab

https://research.thinkwood.com/en/permalink/catalogue2720
Year of Publication
2020
Topic
Connections
Material
CLT (Cross-Laminated Timber)
Application
Floors
Author
Zhukov, Pavel
Publisher
Hämeenlinna University Center
Year of Publication
2020
Format
Thesis
Material
CLT (Cross-Laminated Timber)
Application
Floors
Topic
Connections
Keywords
Composite Beam
Timber Slab
Connection Details
Connectors
Language
English
Research Status
Complete
Summary
The aim of the Bachelor’s thesis was to describe and evaluate the most common connection details between steel-concrete composite (SCC) beam DELTABEAM® and Cross-Laminated Timber (CLT) slab in two variations: with and without concrete topping. The purpose of the thesis was to provide a basis for future studies that are to expand the CLT range of appliance in Finland. The thesis was based on a theoretical description of the four different connectors that utilize the same working principles as the connections used for joining concrete floor slabs and the beam using the German standard details. The calculations were done according to the Eurocode 1995 and German timber design code DIN1052. The result of the thesis was the connection details library. The result of the study allows to conclude that by using described connection details, the CLT slabs and DELTABEAM® form a reliable flooring system.
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Free
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Developing a Large Span Timber-based Composite Floor System for Highrise Office Buildings Phase I

https://research.thinkwood.com/en/permalink/catalogue2803
Year of Publication
2021
Topic
Design and Systems
Material
CLT (Cross-Laminated Timber)
LVL (Laminated Veneer Lumber)
LSL (Laminated Strand Lumber)
Glulam (Glue-Laminated Timber)
Application
Floors
Author
Zhang, Chao
Lee, George
Lam, Frank
Organization
University of British Columbia
Year of Publication
2021
Country of Publication
Canada
Format
Report
Material
CLT (Cross-Laminated Timber)
LVL (Laminated Veneer Lumber)
LSL (Laminated Strand Lumber)
Glulam (Glue-Laminated Timber)
Application
Floors
Topic
Design and Systems
Keywords
Box Girder
Timber Composite Floor
Span
High-Rise
Tall Wood Buildings
Stiffness
Composite Action
Language
English
Research Status
Complete
Summary
This project proposes a timber-based composite floor that can span 12 m and be used in the construction of 40+ story office buildings. This floor system integrates timber panels and timber beams to form a continuous box girder structure. The timber panels function as the flanges and the timber beams as the web. The beams are spaced and connected to the flange panels so that sufficient bending stiffness of a 12 m span can be achieved via the development of composite action. The current phase of this project studied the performance of the connections between timber elements in the proposed composite member. Six types of connections using different flange material and connection techniques were tested: Cross Laminated Timber (CLT), Laminated Strand Lumber (LSL), Laminated Veneer Lumber (LVL), and Post Laminated Veneer Lumber (PLVL). Glulam was used as the web. The majority of the connections used self-tapping wood screws except one had notches. The load-carrying capacity, stiffness, and ductility of the connections were measured. The stiffness of CLT, LSL, and PLVL connections was in the same range, 19-20 kN/mm per screw. Amongst the three, LSL had the highest peak load and PLVL had the highest proportional limit. The stiffness of the two LVL screw connections was around 13 kN/mm. The notched LVL connection had significantly higher stiffness than the rest, and its peak load was in the same range as LSL, but the failure was brittle. LVL was used to manufacture the full scale timber composite floor element. With a spacing of 400 mm, the overall stiffness reached 33689 N
mm2×109, which was 2.5 times the combined stiffness of two Glulam beams. The predicted overall stiffness based on Gamma method was within 5% of the tested value, and the estimated degree of composite action was 68%. From both the test results and analytical modeling, the number of screws may be further reduced to 50% or less of the current amount, while maintaining a high level of stiffness. Future work includes testing the composite floor under different screw spacings, investigating the effect of concrete topping, and the connections between floor members and other structural elements.
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Dynamic Performance of Timber and Timber-Concrete Composite Flooring Systems

https://research.thinkwood.com/en/permalink/catalogue229
Year of Publication
2013
Topic
Connections
Serviceability
Material
LVL (Laminated Veneer Lumber)
Timber-Concrete Composite
Application
Floors
Author
Rijal, Rajendra
Organization
University of Technology Sydney
Year of Publication
2013
Country of Publication
Australia
Format
Thesis
Material
LVL (Laminated Veneer Lumber)
Timber-Concrete Composite
Application
Floors
Topic
Connections
Serviceability
Keywords
Connections
Costs
Fasteners
Finite Element Model
Long Span
Multi-Storey
Sustainability
Vibrations
Small Scale
Static Load Tests
Damage Index (DI) Method
Loss of Composite Action Index (LCAI)
Language
English
Research Status
Complete
Summary
The work presented in this thesis deals with the investigation of the dynamic performance of timber only and TCC flooring systems, which is one of the sub-objectives of the research focus at UTS. In particular, the presented research assesses the dynamic performance of long-span timber and TCC flooring systems using different experimental und numerical test structures. For the experimental investigations, experimental modal testing and analysis is executed to determine the modal parameters (natural frequencies, damping ratios and mode shapes) of various flooring systems. For the numerical investigations, finite element models are calibrated against experimental results, and are utilised for parametric studies for flooring systems of different sizes. Span tables are generated for both timber and TCC flooring systems that can be used in the design of long-span flooring systems to satisfy the serviceability fundamental frequency requirement of 8 Hz or above. To predict the fundamental frequency of various TCC beams and timber floor modules (beams), five different analytical models are utilised and investigated. To predict the cross-sectional characteristics of TCC systems and to identify the effective flexural stiffness of partially composite beams, the “Gamma method” is utilised. [...] two novel methods are developed in this thesis that determines the degree of composite action of timber composite flooring systems using only measurements from non-destructive dynamic testing. The core of both methods is the use of an existing mode-shape-based damage detection technique, namely, the Damage Index (DI) method to derive the loss of composite action indices (LCAIs) named as LCAI1 and LCAI2. The DI method utilises modal strain energies derived from mode shape measurements of a flooring system before and after failure of shear connectors. The proposed methods are tested and validated on a numerical and experimental timber composite beam structure consisting of two LVL components (flange and web). To create different degrees of composite action, the beam is tested with different numbers of shear connectors to simulate the failure of connection screws. The results acquired from the proposed dynamic-based method are calibrated to make them comparable to traditional static-based composite action results. It is shown that the two proposed methods can successfully be used for timber composite structures to determine the composite action using only mode shapes measurements from dynamic testing.
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External Thermal Insulation Composite Systems in Solid Timber Construction

https://research.thinkwood.com/en/permalink/catalogue1639
Year of Publication
2016
Topic
Serviceability
Moisture
Material
CLT (Cross-Laminated Timber)
Application
Wood Building Systems
Author
Günther, Simon
Ringhofer, Andreas
Schickhofer, Gerhard
Year of Publication
2016
Country of Publication
Austria
Format
Conference Paper
Material
CLT (Cross-Laminated Timber)
Application
Wood Building Systems
Topic
Serviceability
Moisture
Keywords
External Thermal Insulation Composite Systems
Hygrothermal
Long-term
Monitoring
Temperature
Relative Humidity
Moisture Content
Language
English
Conference
World Conference on Timber Engineering
Research Status
Complete
Notes
August 22-25, 2016, Vienna, Austria p. 3169-3178
Summary
External thermal insulation composite systems (ETICS) combined with cross laminated timber (CLT) reveal useful exterior wall constructions, which meet the requirements for sustainability, serviceability and durability of modern buildings efficiently. Associated thermal insulation and moisture protection requirements are essential design criteria to be considered in the planning process. In light of the European legal regulation concerning ETICS, our paper deals with the hygrothermal behavior of an existing exterior wall construction in solid timber construction with ETICS, experimentally determined by means of long-term monitoring situated in the residential project "_massive_living" (Graz, AT). Based on obtained data of temperature and rel. humidity for a period of two years, we not only evaluated building physics aspects concerning the suitability of the structure, but also derived the time depending course of the essential parameter "moisture content" for selected layers of the CLT element. In addition, corresponding data is compared with results gained from a hygrothermal simulation. Further investigation then was carried out determining the hygrical impact on the timber component by changing insulation material. Therefore, the hygrothermal behavior of commonly applied ETICS in combination with CLT as base material was simulated. Finally, resulting bandwidths of moisture content in dependence of the applied ETICS are shown and discussed.
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Free
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Hybrid CLT-Based Modular Construction Systems for Prefabricated Buildings

https://research.thinkwood.com/en/permalink/catalogue1901
Year of Publication
2018
Topic
Design and Systems
Material
CLT (Cross-Laminated Timber)
Steel-Timber Composite
Application
Wood Building Systems
Floors
Walls

Hybrid Steel-Timber Construction Systems for Social Housing Buildings

https://research.thinkwood.com/en/permalink/catalogue1903
Year of Publication
2014
Topic
Design and Systems
Connections
Material
CLT (Cross-Laminated Timber)
Steel-Timber Composite
Application
Wood Building Systems

Investigating the Structural Performance of a Modular Prefabricated Dry-assembly Mass Timber-steel Hybrid Floor Element

https://research.thinkwood.com/en/permalink/catalogue2816
Topic
Connections
Design and Systems
Material
CLT (Cross-Laminated Timber)
Steel-Timber Composite
Application
Floors
Organization
University of British Columbia
Country of Publication
Canada
Material
CLT (Cross-Laminated Timber)
Steel-Timber Composite
Application
Floors
Topic
Connections
Design and Systems
Keywords
Steel Beams
Steel-timber Composite Floors
Research Status
In Progress
Notes
Project contact is Cristiano Loss at the University of British Columbia
Summary
This research is focused on bridging the current knowledge gap on steel-timber composite floors, where CLT panels are connected to steel beams. Most of the current design codes lack provisions and guidelines for the design of steel-timber composite floors.
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18 records – page 1 of 2.