DESIGN APPROACHES FOR CLT CONNECTIONS
Keywords:
CLT, Connections design, Eurocode 5, CSA O86, NDS, NZ 3603, Embedment, WithdrawalAbstract
Various design approaches for establishing the resistance of connections in cross-laminated timber (CLT) structures have been developed and adopted in timber design standards worldwide. Although the fundamental principles are similar, the new design provisions for CLT connections have been aligned in some standards with the existing design philosophy and format adopted for sawn timber and glulam using traditional fasteners such as dowels, nails, and wood screws for consistency and simplicity, in the other standards, alternate approaches have been developed. This article presents a snap shot of the various design approaches for connections in CLT adopted in Europe, Canada, the United States, and New Zealand. The intent is for the reader to have a better knowledge of the underpinning assumptions, principles, and the adopted design rules in each of these standards.
References
Abukari HA, Cote M, Rogers C, Salenikovich A (2012)
Withdrawal resistance of structural screws in Canadian
glued laminated timber. Proc. WCTE 2012, July 15-19,
, Auckland, New Zealand.
AWC, National Design Specifications for Wood Construction
(ANSI/AWC NDS-2015), Leesburg (VA): American
Wood Council, 2015.
Austrian Standards Institute (ASI) (2015) Eurocode 5: Design
of timber structures—Part 1-1: General—Common
rules and rules for buildings—National specifications for
the implementation of O¨ NORM EN 1995-1-1, national
comments and national supplements. ONORM B 1995-1-
:2015-06. ASI, Vienna, Austria.
Blaß HJ, Bejtka I, Uibel T (2006) Tragfahigkeit von Verbindungen mit selbstbohrenden Holzschrauben mit Vollgewinde (in German). Number 4 in Karlsruher Berichte zum Ingenieurholzbau. KIT Scientific Publishing, Karlsruhe, Germany.
Blaß HJ, Uibel T (2007) Tragfahigkeit von stiftf ormigen
Verbindungsmitteln in Brettsperrholz (in German).
Number 8 in Karlsruher Berichte zum Ingenieurholzbau.
KIT Scientific Publishing, Karlsruhe, Germany.
Brandner R, Flatscher G, Ringhofer A, Schickhofer G, Thiel
A (2016) Cross laminated timber (CLT): Overview and
development. Eur J Wood Wood Prod 74:331-351.
Canadian Standards Association (CSA) (2014) Engineering
design in wood, CSA O86-14, Update # 1, Toronto, ON,
Canada.
European Committee for Standardization (CEN) (2004a)
Eurocode 5: Design of timber structures—Part 1-1:
General—Common rules and rules for buildings. EN
-1-1:2004-11 þ AC:2006-06 þ A1:2008-06 þ A2:
-05. CEN, Brussels, Belgium.
European Committee for Standardization (CEN) (2004b)
Eurocode 5: Design of timber structures—Part 1-2:
General—Structural fire design. EN 1995-1-2:2004-11 þ
AC:2006-06 þ AC:2009-03. CEN, Brussels, Belgium.
European Committee for Standardization (CEN) (2004c)
Eurocode 5: Design of timber structures—Part 2: Bridges.
EN 1995-2:2004. CEN, Brussels, Belgium.
European Committee for Standardization (CEN) (2016)
Structural timber—Strength classes. EN 338-2016-06.
CEN, Brussels, Belgium.
European Technical Approval ETA-11/0030 (2012) RothoBlaas
self-tapping screws. EOTA.
Franke S, Quenneville P (2011) Bolted and dowelled connections in radiate pine and laminated veneer lumber using
the European yield model. Aust J Struct Eng 12(1):13-28.
German Institute for Standardization (DIN) (2013) National
annex—Nationally determined parameters—Eurocode 5:
Design of timber structures—Part 1-1: General—Common
rules and rules for buildings. DIN EN 1995-1-1/NA:2013-
DIN, Berlin, Germany.
German National Technical Approval Z-9 1-482 (2015)
KLH-Kreuzlagenholz. DIN, Berlin, Germany.
Hubner U (2013) Withdrawal strength of self-tapping screws
in hardwoods. International council for research and innovation in building and construction. Working commission
W18—Timber Structures. Meeting 46 Vancouver, Canada, August 2013.
Johansen KW (1949) Theory of timber connections. Pages
-262 in International Association for Bridge and
Structural Engineering, Vol. 9.
Kennedy S, Salenikovich A, Munoz W, Mohammad M
(2014) Design equations for dowel embedment strength and
withdrawal resistance for threaded fasteners in CLT. Proc.
WCTE 2014, August 10-14, Quebec City, QC, Canada.
Kennedy S, Salenikovich A, Muñoz W, Mohammad M
(2014a) Design equations for dowel embedment strength
and withdrawal resistance for threaded fasteners in CLT.
In: Proceedings of the World Conference on Timber Engineering 2014, August 10-14, 2014, Quebec City,
Canada.
Kennedy S, Salenikovich A, Muñoz W, Mohammad M,
Sattler D (2014b) Design equations for embedment
strength of wood for threaded fasteners in the Canadian
timber design code. In: Proceedings of the World Conference
on Timber Engineering 2014, August 10-14, 2014, Quebec City, Canada.
Kennedy S, Salenikovich A, Muñoz W, Mohammad M
(2014c) Design equation for withdrawal resistance of
threaded fasteners in the Canadian timber design code. In:
Proceedings of the World Conference on Timber Engineering
, August 10-14, 2014, Quebec City, Canada.
Kleinhenz M, Winter S, Dietsch P (2016) Eurocode 5—A
halftime summary of the revision process. Proc. 2016
World Conference on Timber Engineering (WCTE),
August 22-25, 2016, Vienna, Austria.
Mohammad M, Quenneville P, Salenikovich A, Zarnani P,
MunozW(2014) Failure modes in CLT connections. Proc.
World Conference on Timber Engineering (WCTE),
August 10-14, Quebec City, QC, Canada.
NZS3603:1993 (1993) Timber structures standard. Standards
New Zealand, Wellington, New Zealand.
NZS1170.5:2004 (2004) Structural design actions part 5:
Earthquake actions—New Zealand. Standards New Zealand,
Wellington, New Zealand.
Ottenhaus L-M, Li M, Smith T, Quenneville P (2016)
Ductility and overstrength of dowelled LVL and CLT
connections under cyclic loading. Proc. 2016 World
Conference on Timber Engineering, August 22-25, 2016,
Vienna, Austria.
Pirnbacher G, Schickhofer G (2012) Zeitabh¨angige Entwicklung der Traglast und des Kriechverhaltens von axial beanspruchten, selbstbohrenden Holzbauschrauben (in German). Research Report. holz.bau forschungs gmbh, Graz, Austria.
Ringhofer A, Brandner R, Schickhofer G (2015) Withdrawal
resistance of self-tapping screws in unidirectional and
orthogonal layered timber products. Mater Struct 48(5):
-1447.
Ringhofer A (2017) Axially loaded self-tapping screws in
solid timber and laminated timber products. Dissertation.
Graz University of Technology, Graz, Austria.
Toratti T (2016) The standardization chain in Europe:Material Design—Execution. Proc. 2016 World Conference on
Timber Engineering (WCTE), August 22-25, 2016,
Vienna, Austria.
Uibel T, Blaß HJ (2006) Load carrying capacity of joints with
dowel type fasteners in solid wood panels. International
council for research and innovation in building and construction. Working commission W18—Timber structures.
Meeting 39 Florence, Italy, August 2006.
Uibel T, Blaß HJ (2007) Edge joints with dowel type fasteners
in cross-laminated timber. International council for
research and innovation in building and construction.
Working commission W18—Timber structures. Meeting
Bled, Slovenia, August 2007.
Uibel T, Blaß HJ (2013) Joints with dowel type fasteners
in CLT structures. Pages 119-134 in R Harris, A Ringhofer,
and G Schickhofer, eds. Proc. Focus Solid Timber
Solutions—European Conference on Cross Laminated
Timber, Edition 2, May 21-22, 2013, Graz, Austria.
Downloads
Published
Issue
Section
License
The copyright of an article published in Wood and Fiber Science is transferred to the Society of Wood Science and Technology (for U. S. Government employees: to the extent transferable), effective if and when the article is accepted for publication. This transfer grants the Society of Wood Science and Technology permission to republish all or any part of the article in any form, e.g., reprints for sale, microfiche, proceedings, etc. However, the authors reserve the following as set forth in the Copyright Law:
1. All proprietary rights other than copyright, such as patent rights.
2. The right to grant or refuse permission to third parties to republish all or part of the article or translations thereof. In the case of whole articles, such third parties must obtain Society of Wood Science and Technology written permission as well. However, the Society may grant rights with respect to Journal issues as a whole.
3. The right to use all or part of this article in future works of their own, such as lectures, press releases, reviews, text books, or reprint books.
