Abstract
This paper presents the results of an extensive experimental programme on typical cross-laminated timber (CLT) screwed connections conducted at CNR-IVALSA research institute. In-plane monotonic and cyclic shear and withdrawal tests were performed on screwed wall-to-wall, floor-to-floor and wall-to-floor CLT connections. Mechanical properties such as strength, stiffness, energy dissipation, ductility ratio and impairment of strength were evaluated. The experimental results showed good performance of CLT screwed joints under cyclic loads when ductile behaviour was achieved. Brittle response occurred only in cases where requirements for end and edge distances were not satisfied. The experimental characteristic shear strength and mean slip modulus of the connections were compared with values obtained using analytical design equations. The Eurocode 5 (EC5) formulas overestimated the characteristic strength values in some cases, while the Uibel and Blaß formulas specifically developed for CLT connections provided more accurate and conservative predictions. In cases where brittle failures were attained, the analytical values overestimated the experimental ones. This issue can be avoided when the requirements for minimum edge and end distances stated by EC5 are fulfilled. EC5 empirical formulas for the prediction of the screw connection slip modulus at serviceability limit state corresponded well with the experimental elastic values. The overstrength factor, which is of great importance in capacity-based design, was also evaluated, and a conservative value of 1.6 can be recommended for screwed CLT connections.
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References
Bratulic K, Flatscher G, Brandner R (2014) Monotonic and cyclic behavior of joints with self-tapping screws in CLT structures. In: proceedings of the COST action FP1004 conference on experimental research with timber, Prague (Czech Republic)
Ceccotti A (2008) New technologies for construction of medium-rise buildings in seismic regions: the XLAM case. J Int Assoc Bridge Struct Eng 2:156–165
Ceccotti A, Lauriola M, Pinna M, Sandhaas C (2006) SOFIE project—cyclic tests on cross-laminated wooden panels. In: proceedings of the 9th world conference on timber engineering, Portland, Oregon, USA
Ceccotti A, Sandhaas C, Okabe M, Yasumura M, Minowa C, Kawai N (2013) SOFIE project—3D shaking table test on a seven-storey full-scale cross-laminated building. Earthq Eng Struct Dyn 42(13):2003–2021
CSA O86-09 (2009) Engineering design in wood. Canadian Standard Association, Mississauga, Ontario, Canada
Dujic B, Zarnic R (2005) Report on evaluation of racking strength of KLH system. University of Ljubljana, Faculty of civil and geodetical engineering, Slovenia
EN 12512 (2001) Timber structures—test methods—cyclic testing of joints made with mechanical fasteners. CEN, Brussels, Belgium
EN 14358 (2007) Timber structures—calculation of characteristic 5-percentile values and acceptance criteria for a sample. CEN, Brussels, Belgium
EN 1995-1-1 (2004) Eurocode 5: design of timber structures—part 1-1: general rules and rules for buildings. CEN, Brussels, Belgium
EN 1998-1 (2003) Eurocode 8: design of structures for earthquake resistance—part 1: general rules, seismic actions and rules for buildings. CEN, Brussels, Belgium
EN 384 (2005) Structural timber—determination of characteristic values of mechanical properties and density. CEN, Brussels, Belgium
ETA-11/0030 (2011) European technical approval. Self-tapping screws for use in timber structures. European Organisation for Technical Approvals, Brussels, Belgium
Follesa M, Brunetti M, Cornacchini R, Grasso S (2010) Mechanical in-plane joints between cross laminated timber panels. In: proceeding of the 11th world conference on timber engineering, Riva del Garda, Italy
Follesa M, Christovasilis IP, Vassallo D, Fragiacomo M, Ceccotti A (2013) Seismic design of multi-storey CLT buildings according to Eurocode 8. Ingegneria Sismica/Int J Earthq Eng, Special Issue on timber structures, 4 October–December 2013:27–53
Fragiacomo M, Dujic B, Sustersic I (2011) Elastic and ductile design of multi-storey crosslam massive wooden buildings under seismic actions. Eng Struct 33(11):3043–3053
Gavric I (2013) Seismic behaviour of cross-laminated timber buildings, Ph.D. Thesis, University of Trieste, Italy. http://hdl.handle.net/10077/8638
Gavric I, Fragiacomo M, Ceccotti A (2012) Strength and deformation characteristics of typical CLT connections. In: proceeding of the 12th world conference on timber engineering, Auckland, New Zealand
Gavric I, Fragiacomo M, Ceccotti A (2013) Capacity seismic design of CLT wall systems based on connection mechanical properties. In: proceedings of the 46th CIB-W18 meeting, Paper 46-15-2, Vancouver, Canada
Gavric I, Fragiacomo M, Ceccotti A (2014a) Cyclic behavior of cross-laminated timber (CLT) wall systems: experimental tests and analytical prediction models. ASCE J Struct Eng (accepted)
Gavric I, Fragiacomo M, Ceccotti A (2014b) Cyclic behaviour of typical metal connectors for cross-laminated (CLT) structures. Mater Struct. doi:10.1617/s11527-014-0278-7 (published online)
Jorissen A, Fragiacomo M (2011) General notes on ductility in timber structures. Eng Struct 33(11):2987–2997
Joyce T, Smith I, Ballerini M (2011) Mechanical behaviour of in-plane shear connections between CLT wall panels. In: proceedings of 44th CIB-W18 meeting, Paper 44-7-2, Alghero, Italy
Lauriola MP, Sandhaas C (2006) Quasi-static and pseudo-dynamic tests on XLAM walls and buildings. Cost E29 international workshop on earthquake engineering on timber structures, pp 119–133, Coimbra, Portugal
Muñoz W, Mohammad M, Gagnon S (2010) Lateral and withdrawal resistance of typical CLT connections. In: proceedings of the 11th world conference on timber engineering, Riva del Garda, Italy
Rinaldin G, Amadio C, Fragiacomo M (2013) A Component approach for the hysteretic behaviour of connections in cross-laminated wooden structures. Earthq Eng Struct Dyn 42(13):1885–2042
Sandhaas C, Boukes J, Van de Kuilen JWG, Ceccotti A (2009) Analysis of X-lam panel-to-panel connections under monotonic and cyclic loading. In: proceedings of 42nd CIB-W18 meeting, Paper 42-12-2, Dübendorf, Switzerland
Uibel T, Blaß HJ (2006) Load carrying capacity of joints with dowel type fasteners in solid wood panels. In: proceedings of the 43rd CIB-W18 meeting, Paper 39-7-5, Florence, Italy
Uibel T, Blaß HJ (2007) Edge joints with dowel type fasteners in cross laminated timber. In: proceedings of the 44th CIB-W18 meeting, Paper 40-7-2, Bled, Slovenia
Acknowledgments
The experimental programme presented in this paper was funded by the Autonomous Province of Trento (Italy) within the SOFIE research project. The analytical research was funded with the grant: ‘The application in Sardinia of the new Italian technical rules for Construction’ by the Sardinia Region within the “Funds for Research Projects on Selected Topics of Strict Regional Interest”. The authors would like to acknowledge the contribution to this research of IVALSA laboratory staff Mario Pinna, Diego Magnago and Paolo Dellantonio, who provided technical expertise for the experimental testing.
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I. Gavric formerly worked in University of Sassari.
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Gavric, I., Fragiacomo, M. & Ceccotti, A. Cyclic behavior of typical screwed connections for cross-laminated (CLT) structures. Eur. J. Wood Prod. 73, 179–191 (2015). https://doi.org/10.1007/s00107-014-0877-6
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DOI: https://doi.org/10.1007/s00107-014-0877-6