Ultra-Thin Topping Upgrades for Improved Serviceability Performance

Article Preview

Abstract:

Timber floors can be refurbished by connecting a concrete topping to the timber joists; stiffening the floor and reducing serviceability problems, including vibration. Research to date has focused on upgrade solutions with relatively thick toppings (40mm or greater). This paper presents a novel, ultra-thin topping solution where the topping is placed at a thickness of 20mm or less. Advantages of the solution include: reducing the mass added to the existing structure and minimising the change in floor to ceiling height whilst delivering a significant increase in floor stiffness. This paper reports the findings from the serviceability testing of an upgraded, full scale timber floor. Measurements prior to and after the upgrade are compared, including: elastic testing under static loads, vibration testing and short-term bending tests. The paper also compares the results with simple analytical approaches and design limits prescribed in Eurocode 5 Part 1-1.

You might also be interested in these eBooks

Info:

Periodical:

Pages:

673-681

Citation:

Online since:

September 2013

Export:

Price:

Permissions CCC:

Permissions PLS:

Сopyright:

© 2013 Trans Tech Publications Ltd. All Rights Reserved

Share:

Citation:

[1] A. Ceccotti, Composite concrete-timber structures, Progress in Structural Engineering and Materials, 4 (2002) 264-275.

DOI: 10.1002/pse.126

Google Scholar

[2] M. Fragiacomo, Experimental behaviour of a full-scale timber-concrete composite floor with mechanical connectors: accepted to Materials and Structures (2012).

DOI: 10.1617/s11527-012-9869-3

Google Scholar

[3] M. Fragiacomo, C. Amadio, L. Macorini, Short and long-term performance of the Tecnaria, stud connector for timber-concrete composite beams, Materials and Structures, 40 (2006) 1013-1026.

DOI: 10.1617/s11527-006-9200-2

Google Scholar

[4] C. Mertens, Y. Martin, F. Dobbels, Investigation of the vibration behaviour of timber-concrete composite floors as part of a performance evaluation for the belgian building industry, Building Acoustics, 14 (2007) 25-36.

DOI: 10.1260/135101007780661383

Google Scholar

[5] L.J. Hu, Y.H. Chui, I. Smith, Serviceability of wood floor systems with concrete topping, in: Proceedings of the 5th World Conference on Timber Engineering, 2 (1998) 750-751, Montreaux, Switzerland.

Google Scholar

[6] Comité Européen de Normalisation (CEN), ENV 1995. Eurocode 5 - Design of timber structures – part 1-1: General - common rules and rules for buildings. prEN 1995: 1-1, CEN, Brussels, (2004).

DOI: 10.3403/03174906

Google Scholar

[7] A. Frangi, M. Fontana, Elasto-plastic model for timber-concrete composite beams with ductile connection, Structural Engineering International, 13 (2003) 47-57.

DOI: 10.2749/101686603777964856

Google Scholar

[8] A. Ceccotti, Timber-concrete composite structures, in: H.J. Blass, P. Aune, B.S. Choo, R. Görlacher, R.D. Griffiths, B.O. Hilson, P. Racher, G. Steck (Eds. ), Timber Engineering, STEP 2, Centrum Hout, The Netherlands, 1995, pp. E13/1-E13/12.

Google Scholar

[9] R. Gutkowski, K. Brown, A. Shigidi, J. Natterer, Laboratory tests of composite wood-concrete beams, Construction and Building Materials, 22 (2008) 1059-1066.

DOI: 10.1016/j.conbuildmat.2007.03.013

Google Scholar

[10] R.F.S. Hearmon, The fundamental frequency of vibration of rectangular wood and plywood plates, Proceedings of the Physical Society, 58 (1946) 78-92.

DOI: 10.1088/0959-5309/58/1/307

Google Scholar

[11] J. Skinner, R. Harris, K. Paine, P. Walker, Considerations for the inclusion of expressions in eurocode 5 to assess the vibrational performance of timber-concrete composites - research note, in: CIB-W18 - Timber Structures, (2011) Alghero, Italy.

Google Scholar

[12] S. Ohlsson, Springiness and Human-Induced Floor Vibrations: a Design Guide, Swedish Council for Building Research, Stockholm, (1988).

Google Scholar

[13] J. Skinner, R. Harris, K. Paine, P. Walker, J. Bregulla, The characterisation of connectors for the upgrade of timber floors with thin structural toppings, in: Proceedings of the 12th World Conference on Timber Engineering, (2012).

Google Scholar

[14] CEN, EN 26891, Timber structures - Joints made with mechanical fasteners: General principles for the determination of strength and deformation characteristics, CEN, Brussels, (1991).

DOI: 10.3403/00248652u

Google Scholar

[15] CEN, NA to EN 1995-1-1: 2004, UK national annex to eurocode 5: Design of timber structures - part 1-1: General - common rules and rules for buildings, (2006).

DOI: 10.3403/30391838

Google Scholar

[16] Y.H. Chui, Vibrational performance of timber floors and the related human discomfort criteria, Institute of Wood Science, 10 (1986) 183-188.

Google Scholar

[17] M. Fragiacomo, E. Lukaszewska, Development of prefabricated timber-concrete composite floor systems, Proceedings of the Institution of Civil Engineers: Structures and Buildings, 164 (2011) 117-129.

DOI: 10.1680/stbu.10.00010

Google Scholar

[18] E. Lukaszewska, H. Johnsson, M. Fragiacomo, Performance of connections for prefabricated timber - concrete composite floors, Materials and Structures, 41 (2008) 1533-1550.

DOI: 10.1617/s11527-007-9346-6

Google Scholar

[19] A. Stearn, Timber-concrete composites constructed with thin concrete toppings - tested in flexure, MEng dissertation, University of Bath, (2006).

Google Scholar