Enhanced Seismic Systems for Mass-Timber Structures

Mass-timber provides numerous benefits in reducing structural material impact on the environment by limiting building embodied carbon. Mass timber from sustainably harvested farms is a renewable material and considered a sink from wood carbon sequestration, and the reduced weight of mass timber framed buildings results in less lateral system and foundation materials.Timber’s limited ductility and traditional connections limit applications in high-seismic regions, but a series of novel connections can reliably provide ductility by using friction to dissipate energy, protecting timber elements as they remain essentially elastic. The bolted connections are designed to be easily replaceable after an earthquake and can re-center the building under any residual drift. In these systems, the seemingly incompatible concepts of resilient and sustainable design can be achieved concurrently, using a renewable material for the base material and connections which specifically target faster recovery times.The Pin-Fuse® Joint and Link-Fuse™ Joint systems, used in moment resisting timber frames and cross- laminated timber shear walls systems, rely on slipping of pre-tensioned bolts across friction surfaces to simulate material yielding. This paper will review the theory behind the systems, application of the devices in timber structures, and compare enhanced seismic design to conventional design timber buildings.

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Hysteresis loops for timber structures

Bulletin of the New Zealand Society for Earthquake Engineering ◽

10.5459/bnzsee.19.2.143-152 ◽

1986 ◽

Vol 19 (2) ◽

pp. 143-152 ◽

Cited By ~ 9

Author(s):

D. J. Dowrick

Keyword(s):

Hysteresis Loops ◽

Shear Walls ◽

Computer Models ◽

Timber Structures ◽

Side Plate ◽

Hysteretic Behaviour ◽

Moment Resisting ◽

Pull Tests

This paper reviews experimentally determined hysteresis loops for timber structures, including moment-resisting joints with (i) steel and (ii) plywood side plates, (iii) shear walls clad with various materials, and (iv) push-pull tests on various connection details. The paper compares bending and push-pull hysteresis loops for nailed steel side-plate joints. An attempt is made to classify the above hysteretic behaviour for analytical purposes, and the available computer models are reviewed for applicability to these hysteresis shapes.

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Lateral resistance of mass timber shear wall connected by withdrawal-type connectors

Journal of Wood Science ◽

10.1186/s10086-021-01967-7 ◽

2021 ◽

Vol 67 (1) ◽

Author(s):

Sung-Jun Pang ◽

Kyung-Sun Ahn ◽

Seog Goo Kang ◽

Jung-Kwon Oh

Keyword(s):

Experimental Data ◽

Seismic Design ◽

Shear Walls ◽

Shear Wall ◽

Vertical Load ◽

Lateral Resistance ◽

Kinematic Models ◽

Mass Timber ◽

Timber Shear Walls ◽

Timber Shear Wall

AbstractIn this study, the lateral resistances of mass timber shear walls were investigated for seismic design. The lateral resistances were predicted by kinematic models with mechanical properties of connectors, and compared with experimental data. Four out of 7 shear wall specimens consisted of a single Ply-lam panel and withdrawal-type connectors. Three out of 7 shear wall specimens consisted of two panels made by dividing a single panel in half. The divided panels were connected by 2 or 4 connectors like a single panel before being divided. The applied vertical load was 0, 24, or 120 kN, and the number of connectors for connecting the Ply-lam wall-to-floor was 2 or 4. As a result, the tested data were 6.3 to 52.7% higher than the predicted value by kinematic models, and it means that the lateral resistance can be designed by the behavior of the connector, and the prediction will be safe. The effects of wall-to-wall connectors, wall-to-floor connectors and vertical loads on the shear wall were analyzed with the experimental data.

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Experimental Investigation of Steel Plate Shear Walls under Shear-Compression Interaction

Shock and Vibration ◽

10.1155/2019/8202780 ◽

2019 ◽

Vol 2019 ◽

pp. 1-11

Author(s):

Yang Lv ◽

Ling Li ◽

Di Wu ◽

Bo Zhong ◽

Yu Chen ◽

...

Keyword(s):

Stress Distribution ◽

Steel Plate ◽

Axial Stress ◽

Shear Walls ◽

Shear Capacity ◽

Steel Plate Shear Walls ◽

Steel Plate Shear Wall ◽

Gravity Load ◽

Moment Resisting ◽

Axial Stress Distribution

Four scaled one-storey single-bay steel plate shear wall (SPSW) specimens with unstiffened panels were tested to determine their behaviour under cyclic loadings. The shear walls had moment-resisting beam-to-column connections. Four different vertical loads, i.e., 300 kN, 600 kN, 900 kN, and 1200 kN, representing the gravity load of the upper storeys were applied at the top of the boundary columns through a force distribution beam. A horizontal cyclic load was then applied at the top of the specimens. The specimen behaviour, envelope curves, axial stress distribution of the infill steel plate, and shear capacity were analyzed. The axial stress distribution and envelope curves were compared with the values predicted using an analytical model available in the literature.

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Residual Drift Estimation for Moment Resisting Frames with Steel Degradation Properties

ce/papers ◽

10.1002/cepa.1504 ◽

2021 ◽

Vol 4 (2-4) ◽

pp. 1917-1923

Author(s):

Borjan Petreski ◽

Igor Gjorgjiev

Keyword(s):

Residual Drift ◽

Moment Resisting Frames ◽

Drift Estimation ◽

Moment Resisting ◽

Degradation Properties

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Durability and protection of mass timber structures: A review

Journal of Building Engineering ◽

10.1016/j.jobe.2021.103731 ◽

2021 ◽

pp. 103731

Author(s):

Samuel Ayanleye ◽

Kenneth Udele ◽

Vahid Nasir ◽

Xuefeng Zhang ◽

Holger Militz

Keyword(s):

Timber Structures ◽

Mass Timber

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Structural Systems for Mass Timber Buildings

IABSE Congress, New York, New York 2019: The Evolving Metropolis ◽

10.2749/newyork.2019.1156 ◽

2019 ◽

Cited By ~ 1

Author(s):

Tim Gleason ◽

Gordana Herning ◽

John Klein

Keyword(s):

Affordable Housing ◽

Lateral Force ◽

Timber Structures ◽

Braced Frames ◽

Conventional Concrete ◽

Composite Systems ◽

Lateral Resistance ◽

Mass Timber ◽

Story Building ◽

Gravity System

This paper investigates the design of lateral force resisting systems (LFRS) for multi-story mass timber structures in Boston, MA. Structural and environmental tradeoffs of replacing conventional concrete cores or steel braced frames with glue-laminated timber (GLT) braced frames are evaluated through numerical analyses of 8-, 12-, and 18-story building prototypes. Finding an optimal timber gravity system configuration is followed by examining lateral resistance of the prototypes. The resulting designs demonstrate a practical approach to assist designers in selecting a lateral system during the early stages of conceptual design. This research was conducted in parallel with a related study for implementation of mass timber in affordable housing in Boston, enabling a comparison between composite systems and all-timber structures.

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The Use of Moment-Resisting Frames and Braced Frames for Lateral Stability of Multy-Storey Precast Concrete Structures

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.259.173 ◽

2017 ◽

Vol 259 ◽

pp. 173-177

Author(s):

Arthur L. Rocha ◽

Marcelo de A. Ferreira ◽

Wilian dos S. Morais ◽

Bruna Catoia

Keyword(s):

High Performance ◽

Precast Concrete ◽

Tall Buildings ◽

Shear Walls ◽

Order Effects ◽

Lateral Stability ◽

Infill Walls ◽

Precast Buildings ◽

Moment Resisting ◽

Lateral Displacements

Precast structures for multi-storey buildings can be designed with economy, safety and high performance. However, depending on the height of the building and the intensity of the lateral loads, the lateral stability system must be carefully chosen in order to maximize the global structural performance. In Brazil, the most common method for lateral stability is achieved by moment resisting precast-frames, wherein the moment-rotation response of the beam-column connections are responsible to provide the frame action, which will govern the distribution of internal forces and the sway distribution along the building height. On the other hand, in Europe, bracing systems comprised by shear walls or infill walls are mostly used, wherein beam-column connections are designed as hinged. The aim of this paper is to present a comparison between these methods for lateral stability, applying nine structural simulations with moment resisting precast-frames, shear walls and infill walls solutions, divided in three groups - 3 building with 5 storeys (21 meters high), 3 buildings with 10 storeys (41 meters high) and 3 building with 20 storeys (81 meters high). All first storeys are 5 meters high, while all the others are 4 meters high. The results from all structural analyses are compared. As conclusion, while moment-resisting beam-column connections are more feasible for applying in low-rise precast buildings, the use of shear walls and infill walls are more efficient for tall buildings due to decrease of lateral displacements, having a reduction of second order effects but also increasing the reactions at the foundations of bracing elements.

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Analysis of hygroscopic self-shaping wood at large scale for curved mass timber structures

Science Advances ◽

10.1126/sciadv.aax1311 ◽

2019 ◽

Vol 5 (9) ◽

pp. eaax1311 ◽

Cited By ~ 7

Author(s):

Philippe Grönquist ◽

Dylan Wood ◽

Mohammad M. Hassani ◽

Falk K. Wittel ◽

Achim Menges ◽

...

Keyword(s):

Large Scale ◽

Manufacturing Industry ◽

Deformation Mechanisms ◽

Timber Structures ◽

Geometric Complexity ◽

Wood Structures ◽

Material Parameters ◽

Industrial Manufacturing ◽

Shape Prediction ◽

Mass Timber

The growing timber manufacturing industry faces challenges due to increasing geometric complexity of architectural designs. Complex and structurally efficient curved geometries are nowadays easily designed but still involve intensive manufacturing and excessive machining. We propose an efficient form-giving mechanism for large-scale curved mass timber by using bilayered wood structures capable of self-shaping by moisture content changes. The challenge lies in the requirement of profound material knowledge for analysis and prediction of the deformation in function of setup and boundary conditions. Using time- and moisture-dependent mechanical simulations, we demonstrate the contributions of different wood-specific deformation mechanisms on the self-shaping of large-scale elements. Our results outline how to address problems such as shape prediction, sharp moisture gradients, and natural variability in material parameters in light of an efficient industrial manufacturing.

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Experimental Study on Seismic Behaviors of Structural Insulated Panel Shear Walls under Cyclic Loading

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.413.529 ◽

2011 ◽

Vol 413 ◽

pp. 529-534

Author(s):

Hui Feng Yang ◽

Wei Qing Liu ◽

Wei Dong Lu ◽

Shu Ai Yan

Keyword(s):

Bearing Capacity ◽

Failure Modes ◽

Shear Walls ◽

Elastic Stiffness ◽

Width Ratio ◽

Timber Structures ◽

Test Results ◽

Load Bearing Capacity ◽

Panel Shear ◽

Seismic Behaviors

In this paper, a total of five structural insulated panel shear walls (SIPSW), in which with plywood facing and polystyrene foam board core, were tested under low cyclic horizontal loading. For the test specimens, different wall depth-width ratio and the opening sizes have been considered. The failure modes, failure mechanics, bearing capacity, lateral stiffness and ductility are discussed in detail. The test results showed that the hysteretic curve of SIPSW shows a reversed S-shape. Also the depth-to-width ratio and the opening dimensions of the shear walls have significant effects on load bearing capacity, ductility and elastic stiffness. What’s more, the performance of the SIPSW specimens was controlled by the fastener slip behavior of the SIP-to-spline connection, especially along the bottom spline. Finally, it is indicated that SIPSW have a good satisfaction upon seismic performance when used to timber structures.

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