Energy, seismic, and architectural renovation of RC framed buildings with prefabricated timber panels
https://www.mdpi.com/2071-1050/12/12/4845... [Alternative/Hybrid Configurations] [Journal Article] 2020
Margani, G., Evola, G., Tardo, C. and Marino, E.M.
In seismic European countries most of the residential building stock is highly energy-intensive and earthquake-prone because it was built before the enforcement of the most recent energy and seismic codes. Furthermore, this stock often shows a low architectural quality due to poor maintenance and/or construction and design deficiencies: for all these reasons, it needs deep renovation, but the use of common energy and seismic upgrading techniques is often unsustainable in terms of costs, work dur...

Ductility and overstrength of nailed CLT hold-down connections
https://www.sciencedirect.com/science/article/pii/... [Connectors] [Journal Article] 2020
Dong, W., Li, M., Ottenhaus, L.M. and Lim, H.
The structural performance of nailed hold-down connection systems used for cross-laminated timber (CLT) shear walls under monotonic and cyclic loading was experimentally evaluated. Critical connection performance parameters, including strength, stiffness, ductility, and overstrength, were derived from the testing of 68 hold-down connection specimens. The nailed CLT hold-down connections achieved moderate to high ductility when fracture failures of their metal brackets were avoided. The hold-down...

Theoretical Preconditions for Determination of the Elastic Modulus of CLT-Panels
https://www.scientific.net/MSF.992.998... [Mechanical Performance] [Journal Article] 2020
B.V. Labudin, A.V. Karelskiy, D.M. Lyapin
Cross laminated timber panels (CLT) are promising building structures that are actively used in the construction of buildings around the world. In Russia the construction is rarely used, despite the existing factories for their manufacturing. In regulatory documents there are no specific data on the elastic modulus for these structures. As a method for determining this calculated characteristic, a numerical experiment in the SCAD Office software package is proposed. During the experiment, panels...

Modeling the coupling effect of CLT connections under biaxial loading
https://ascelibrary.org/doi/abs/10.1061/(ASCE)ST.1... [Connectors] [Journal Article] 2020
Jingjing Liu, Frank Lam, Ricardo O. Foschi, Minghao Li
This paper presents the modeling of coupling effect of tension and shear loading on cross-laminated timber (CLT) connections using a finite-element–based algorithm called HYST developed in 2000. The model idealizes the connections as a pseudonail–elastoplastic beam elements (the nail) surrounded by compression-only spring elements (steel sheath and wood embedment). A gap size factor and an unloading stiffness degradation index of the spring elements under cyclic loading were integrated into the ...

Dynamic increase factors for Radiata pine CLT panels subjected to simulated out-of-plane blast loading
https://www.sciencedirect.com/science/article/pii/... [Raw Materials] [Journal Article] 2020
Van Le, T., Ghazlan, A., Ngo, T., Remennikov, A., Kalubadanage, D. and Gan, E.C.J.
The construction industry, which accounts for almost 20% of Australia’s carbon emissions, is responding to climate change by increasing the demand for sustainable and environmentally friendly materials. Cross-laminated timber (CLT) is an innovative eco-friendly engineering material that can satisfy this demand due to its excellent properties, including fire and seismic resilience, natural insulation and lightweight, to name a few. This study presents the results of 8 blast tests, which were cond...

Evaluation of Bond Integrity in Low-Value Blue-Stain Ponderosa Pine CLT
https://www.researchgate.net/publication/343380910... [Raw Materials] [Conference Paper] 2019
Jahedi, S., Muszynski, L., Riggio, M. and Gupta, R.
National forest restoration programs aim to reduce wildfire risks by selectively removing small-diameter trees from the forest. Each year a large number of Ponderosa pine logs are generated in these operations in Southern Oregon and Northern California. These logs have a very limited market value locally. A substantial portion of them contain blue-stain, which reduce the value even further. It is important to find a value-added market for the logs to offset the high costs of these operations. Ba...

Comparative energy analysis from fire resistance tests on combustible versus noncombustible slabs
https://onlinelibrary.wiley.com/doi/full/10.1002/f... [Fire Performance] [Journal Article] 2019
Alastair I. Bartlett, Robert McNamee, Fabienne Robert, Luke A. Bisby
Standard fire resistance tests have been used in the design of structural building elements for more than a century. Originally developed to provide comparative measures of the level of fire safety of noncombustible products and elements, the recent resurgence in engineered timber construction raises important questions regarding the suitability of standard fire resistance tests for combustible structural elements. Three standard fire resistance floor tests (5.9 m × 3.9 m in plan), one on a conc...

Implementing a Framework for Qualitative Assessment of New Technical Solutions: A Case Study on CLT
https://congress.cimne.com/dbmc2020/admin/files/fi... [Case Study/Projects] [Conference Paper] 2020
C. Tengberg, C. Hagentoft
New technical solutions are introduced at a fast pace in the Swedish construction industry, mainly driven by issues concerning costs and productivity. These new technical solutions can comprise new materials, new goods, new designs but also new processes. The record of accomplishment when introducing new technical solutions in the industry is not unproblematic and serial failures of different new technical solution have occurred. In an earlier interview study exploring introduction of new techni...

The Project Management of Investigating Dowel Laminated Timber
https://digitalcommons.calpoly.edu/arcesp/116/... [Alternative/Hybrid Configurations] [Presentation] 2020
Looney, S.D., Garcia, B.U. and Akkari, R.A.
During the Winter Quarter of 2020, three Architectural Engineering students investigated a new type of timber product, dowel laminated timber, for their senior project. Dowel laminated timber (DLT) is a specialty product typically associated with sustainable design and is a form of mass timber. The three students had little knowledge about mass timber outside of a timber design course; their knowledge was primarily in wood framing design. Therefore, the topic was chosen because dowel laminated t...

Alternative Load Path Analyses for Mid-Rise Post and Beam Mass Timber Building
https://ascelibrary.org/doi/abs/10.1061/9780784482... [Design/Architectural aspects] [Journal Article] 2020
Hercend Mpidi Bita, Robert Malczyk, Thomas Tannert
In addition to gravity and lateral loads, there is a broad range of events that may impact a building during its service life. Amongst these, extreme events such as accidents and natural catastrophes can cause significant damage with a risk of propagation through the structure that can lead to disproportionate collapse. Current standards and guidelines that give direct and indirect approaches to ensure structural robustness are limited to concrete, steel, and light-frame wood structures. Mass ti...

Seismic retrofit of existing frame masonry infill walls by means of sliding joints
https://www.wcee.nicee.org/wcee/article/16WCEE/WCE... [Connectors] [other]
M Preti, 1V Bolis,
The seismic strengthening of existing reinforced concrete structures is a strategic subject in many countries. In Italy, in particular, a large stock of buildings was built from 50 to 70 of the nineteen-century without specific earthquake resistance requirements. Most of them have a reinforced concrete moment resisting frame structure infilled with masonry walls. Recent earthquakes showed that the combined in-plane high stiffness and brittleness of the traditional masonry infills, non-engineered...

Structural performance of post-tensioned CLT shear walls with energy dissipators
https://ascelibrary.org/doi/abs/10.1061/(ASCE)ST.1... [Mechanical Performance] [Journal Article] 2020
Zhiyong Chen; Marjan Popovski; Asif Iqbal
The prestressed-laminated timber (Pres-Lam) system is an innovative low-damage wood-hybrid system that utilizes post-tensioned (PT) mass timber components, e.g., laminated veneer lumber (LVL), glued laminated timber (glulam), and cross laminated timber (CLT), along with various types of energy dissipators, e.g., axial energy dissipators (also called fuses) and U-shaped flexural plates (UFPs). Previous tests carried out on this system focused on scaled (one-third or two-thirds) LVL specimens, whe...

Procedure for parameter identification and mechanical properties assessment of CLT connections
https://www.sciencedirect.com/science/article/pii/... [Connectors] [Journal Article] 2020
Jixing Cao, Haibei Xiong, Lin Chen
Connections in cross-laminated timber (CLT) structures are crucial components that can affect the behaviour of the whole structure. A novel framework that integrates the unscented Kalman filter (UKF) as an estimation tool with a hysteretic model is developed to identify the model parameters of a nonlinear system. The UKF estimates the mean and covariance of the model parameters using unscented transformation (UT) by a set of deterministically chosen sample points. The proposed framework is appli...

Material-based models for post-tensioned shear wall system with energy dissipators
https://www.sciencedirect.com/science/article/pii/... [Mechanical Performance] [Journal Article] 2020
Zhiyong Chen, Marjan Popovski
The Prestressed-Laminated timber system, Pres-Lam, developed in New Zealand, is a low damage innovative wood-hybrid system that utilizes post-tensioned (PT) mass timber components along with various types of energy dissipators. In addition to testing, numerical modelling is another important approach used to investigate the structural performance of Pres-Lam system. In this study, a material-based modelling method was proposed to investigate the seismic performance of Pres-Lam cross-laminated ti...

Fungal damages in Norwegian massive timber elements–a case study
https://www.tandfonline.com/doi/full/10.1080/17480... [Moisture/Durability] [Journal Article] 2020
Mari Sand Austigard, j. Mattsson
Massive timber elements are new in Norway, but their use is increasing. More knowledge is needed regarding the moisture performance of massive timber elements. There is uncertainty regarding the need for vapour barriers or retarders, and construction tents are rarely used despite the elements’ sensitivity to moisture. Twelve massive timber cases from the Mycoteam database, evenly distributed between the construction phase and use phase, have been studied. The types and causes of damage are compa...

A Study on the Block Shear Strength according to the Layer Composition of and Adhesive Type of Ply-Lam CLT
https://www.koreascience.or.kr/article/JAKO2020337... [Mechanical Performance] [Journal Article] 2020
Choi, G.W., Yang, S.M., Lee, H.J., Kim, J.H., Choi, K.H. and Kang, S.G.
In this study, a block shear strength test was conducted to compare and analyze the strength and failure mode on the glued laminated timber, CLT, and Ply-lam CLT, which are mainly used for the construction of wood construction as engineering wood. Through this, the Ply-lam CLT manufacturing conditions for optimum production, such as the type of lamina, plywood, adhesive, and layer composition, were investigated. The results are as follow. Through block shear strength test, it showed high strengt...

Open office acoustics in mass timber construction
https://www.ingentaconnect.com/content/ince/incecp... [Vibration/Acoustic Performance] [Journal Article] 2020
Smith, Valerie; Salter, Ethan
Mass timber construction offers many advantages to the building community. Mass timber construction is lighter weight than typical concrete structures, reduces carbon impact on the environment and offers an aesthetically pleasing ceiling finish. However, this construction can present several acoustical challenges for open office environments, including reduced sound isolation between floors, reduced ceiling absorption within the space, and a greater amount of potentially-feelable vibration when ...

Comparisons on withdrawal resistance of resin and phosphate coated annular ring nails in CLT specimens
https://www.sciencedirect.com/science/article/abs/... [Connectors] [Journal Article] 2020
Aygul Ceylan, Z. Canan Girgin
As a fastener type, the galvanized annular ring nails are common in timber engineering. Nowadays, partially resin or fully phosphate coated annular nails are used as well. In this study, the withdrawal resistance of those nails, whose holding capacities have not been involved in the current literature, is investigated comparing with other nail types (galvanized annular and helical nails) and wood screw via experimental test results on cross-laminated timber (CLT) specimens. Each single fastener ...

Robotic Connections for CLT Panels
http://papers.cumincad.org/cgi-bin/works/paper/caa... [Connectors] [Journal Article] 2020
Joyce, Gabriella and Pelosi, Antony
In a climate where standard methods of construction are being challenged, developments in engineered timbers are allowing mass timber construction to be explored as a sustainable alternative to current building methods that can change the future of the built environment. Cross-laminated timber (CLT) is at the forefront of this evolution and, with the advancement in computational design and digital fabrication tools, there lies an opportunity to redefine standard construction. This project creat...

Sustainable Sonic Environments-The Robotic Fabrication of Mass Timber Acoustic Surfaces
http://papers.cumincad.org/cgi-bin/works/Show?caad... [Other] [Conference Paper] 2020
Peters, Brady, Hoban, Nicholas and Kramer, Krystal
This research proposes that mass timber panels can not only enable a new type of architecture that is sustainable, but that also sounds better. As mass timber construction often exposes the wood structure, and these panels are carefully constructed in factory settings, these panels have the potential to be built so that the acoustically absorptive, reflective, or sound scattering acoustic properties of surfaces can be integrated into the constructive logic and architectural aesthetic of the buil...