Control of Building Sway and Force Flows Using Ultralightweight Slabs
Publication: Journal of Performance of Constructed Facilities
Volume 28, Issue 6
Abstract
Design analyses are presented to demonstrate the technical advantages of substituting ultralightweight slab materials like cross-laminated-timber (CLT) for reinforced concrete (RC) floors and roofs of low-rise and high-rise hybrid building superstructures. Such substitution reduces the gravitational masses of slab by at least two-thirds without reducing functionality as bending or diaphragm slabs. Specific illustrations of design impacts of using CLT are given for hybrid building superstructures where steel or RC frameworks are the primary means of resisting effects of gravity forces associated with occupied built spaces. Results shown apply to two-story buildings in which effects of lateral forces associated with wind or seismic loads are resisted entirely by a steel moment framework, and six- and twenty four–story buildings in which RC shear walls within building cores primarily resist effects of such lateral loads. Consideration is also given to how fire engineering design decisions can impact structural performances of high-rise buildings incorporating combustible slab materials like CLT. The possible fire design solutions considered being complete encapsulation of CLT slabs using noncombustible claddings, and inclusion of RC fire floors vertically separating the superstructure into fire compartments having dimensions typically permitted for combustible construction. In the broad sense, analyses presented here suggest that it is feasible to reduce total gravitational and modal masses of superstructure by at least one-third, with concomitant reductions in superstructure and foundation construction costs. In practice engineers can have many types of lightweight slab construction techniques to choose from, apart from using CLT. Approximate percentage reductions in sway and superstructure force flows quoted herein will scale in proportion to the square-root of the ratio of the masses of RC floor slabs to masses of any substitute floor construction.
Get full access to this article
View all available purchase options and get full access to this article.
Acknowledgments
Funding for this research was provided by the New Brunswick Innovation Foundation under their Research Technician Initiative; the Natural Sciences and Engineering Research Council of Canada under their Discovery Grants Program; and Natural Resources Canada as part of project “UBC07—Development of Value-Added Massive Plate Building Systems” under their Value-to-Wood research program.
References
American Concrete Institute (ACI). (2008). “Building code requirements for structural concrete and commentary.” 318-08, Farmington Hills, MI.
American Institute of Steel Construction (AISC). (2006). Steel construction manual, 13th Ed., Chicago, IL.
American National Standards Institute (ANSI). (2012). “Standard for performance-rated cross-laminated timber.” ANSI/APA PRG 320-2012, New York.
ASCE. (2005). “Minimum design loads for building and structures.” 7-05, Reston, VA.
Asiz, A., and Smith, I. (2009a). “Structural connections for massive timber elements in hybrid structures.” Proc., 33rd IABSE Symp., Bangkok, Thailand, International Association for Bridge and Structural Engineering, Zurich, Switzerland, 7.
Asiz, A., and Smith, I. (2009b). “Demand placed on steel frameworks of tall buildings having massive wood horizontal slabs.” Struct. Eng. Int., 19(4), 395–403.
Buchanan, A. H. (2000). “Fire performance of timber construction.” Progr. Struct. Eng. Mater., 2(3), 278–289.
Canadian Wood Council (CWC). (2010). Wood design manual, Ottawa, ON, Canada.
Ceccotti, A. (2013). “Personal communication, Director of the Italian National Research Council Trees and Timber Institute (CNR-IVALSA).” Trento, Italy.
Computers and Structures (CSI). (2007). Nonlinear structural analysis program SAP2000—Version 11, Berkeley, CA, 450.
Erdle, A., Weckendorf, J., Asiz, A., and Smith, I. (2013).“Effectiveness of distributed mass damper systems for lightweight superstructures.” J. Perform. Constr. Facil., A4014005.
Gagnon, S., and Pirvu, C. (2011). CLT handbook, Special Publication SP-528E, FPInnovations, QC, Canada.
Institute for Research in Construction (IRC). (2010). National Building Code, National Research Council, Ottawa, ON, Canada.
International Code Council (ICC). (2012). International Building Code, Washington, DC.
Ju, S. H., and Lin, M. C. (1999). “Comparison of building analysis assuming rigid or flexible floors.” J. Struct. Eng., 25–31.
Moore, M. A. (2000). “Scotia place—12 story apartment building. A case study of high rise-construction using wood and steel.” Proc., 2000 World Conf. on Timber Engineering, Whistler, BC, Canada, 8.
Smith, I. (2003). “Vibration of timber floors—Serviceability aspects.” Timber engineering, Wiley, Chichester, England, 241–266.
Smith, I., and Frangi, A. (2008). “Overview of design issues for tall timber buildings.” Struct. Eng. Int., 18(2), 141–147.
Smith, I., and Frangi, A. (2014). “Structural use of timber in tall multi-storey buildings, structural engineering document 13.” International Association for Bridge and Structural Engineering, Zurich, Switzerland.
Smith, R. E. (2010). Prefab architecture: A guide to modular design and construction, Wiley, Hoboken, NJ.
Taranath, S. B. (1988). Structural analysis and design of tall buildings, McGraw-Hill, New York.
Weckendorf, J., and Smith, I. (2012). “Dynamic characteristics of shallow floors with cross-laminated-timber spines.” 12th World Conf. Timber Engineering, Auckland, New Zealand.
Wilson, E. (2004). “Static and dynamic analysis of structures.” Computer and structures, 4th Ed., CSI Berkeley, Berkeley, CA, 390.
Information & Authors
Information
Published In
Journal of Performance of Constructed Facilities
Volume 28 • Issue 6 • December 2014
Copyright
© 2014 American Society of Civil Engineers.
History
Received: Jul 11, 2013
Accepted: Jan 9, 2014
Published online: Jan 11, 2014
Published in print: Dec 1, 2014
Discussion open until: Jan 20, 2015
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.