Related titles Transport Properties of Concrete (ISBN 978-1-78242-306-5) Advanced Composites in Bridge Construction and Repair (ISBN 978-0-85709-694-4) Rehabilitation of Metallic Infrastructure Using FRP Composites (ISBN 978-0-85709-653-1) Eco-Efficient Construction and Building Materials (ISBN 978-0-85709-767-5) Woodhead Publishing Series in Civil and Structural Engineering: Number 65 Recent Trends in Cold-Formed Steel Construction Edited by Cheng Yu AMSTERDAM • BOSTON • CAMBRIDGE • HEIDELBERG LONDON • NEW YORK • OXFORD • PARIS • SAN DIEGO SAN FRANCISCO • SINGAPORE • SYDNEY • TOKYO Woodhead Publishing is an imprint of Elsevier Woodhead Publishing is an imprint of Elsevier The Officers’ Mess Business Centre, Royston Road, Duxford, CB22 4QH, UK 50 Hampshire Street, 5th Floor, Cambridge, MA 02139, USA The Boulevard, Langford Lane, Kidlington, OX5 1GB, UK Copyright © 2016 Elsevier Ltd All rights reserved No part of this publication may be reproduced or transmitted in any form or by any 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Charlotte Cockle Production Project Manager: Omer Mukthar Designer: Maria Inês Cruz Typeset by TNQ Books and Journals List of contributors J.C Batista Abreu Bucknell University, Lewisburg, Pennsylvania, United States D Camotim Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal H Chen American Iron and Steel Institute, Washington, DC, United States P.B Dinis Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal G.J Hancock University of Sydney, Sydney, NSW, Australia J Leng Postdoctoral Fellow, Mechanical Engineering Department, McGill University, Montreal, Canada Z Li SUNY Polytechnic Institute, Utica, NY, United States J.B.P Lim W Lu The University of Auckland, Auckland, New Zealand Aalto University, Espoo, Finland A.D Martins Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal D.J Mynors University of Sussex, Brighton, United Kingdom D.A Nethercot C.H Pham University of Sydney, Sydney, NSW, Australia N.A Rahman C.J Wang Imperial College London, London, United Kingdom The Steel Network, Inc., Durham, North Carolina, United States University of Sussex, Brighton, United Kingdom L.W Williams Steel Framing Industry Association Falls Church, VA, United States A.M Wrzesien University of Strathclyde, Glasgow, United Kingdom L Xu University of Waterloo, Waterloo, ON, Canada C Yu University of North Texas, Denton, TX, United States W Zhang Tongji University, Shanghai, China Woodhead Publishing Series in Civil and Structural Engineering 10 11 12 13 14 15 16 17 18 Finite element techniques in structural mechanics C T F Ross Finite element programs in structural engineering and continuum mechanics C T F Ross Macro-engineering F P Davidson, E G Frankl and C L Meador Macro-engineering and the earth U W Kitzinger and E G Frankel Strengthening of reinforced concrete structures Edited by L C Hollaway and M Leeming Analysis of engineering structures B Bedenik and C B Besant Mechanics of solids C T F Ross Plasticity for engineers C R Calladine Elastic beams and frames J D Renton Introduction to structures W R Spillers Applied elasticity J D Renton Durability of engineering structures J Bijen Advanced polymer composites for structural applications in construction Edited by L C Hollaway Corrosion in reinforced concrete structures Edited by H B€ ohni The deformation and processing of structural materials Edited by Z X Guo Inspection and monitoring techniques for bridges and civil structures Edited by G Fu Advanced civil infrastructure materials Edited by H Wu Analysis and design of plated structures Volume 1: Stability Edited by E Shanmugam and C M Wang xii Woodhead Publishing Series in Civil and Structural Engineering 19 Analysis and design of plated structures Volume 2: Dynamics Edited by E Shanmugam and C M Wang Multiscale materials modelling Edited by Z X Guo Durability of concrete and cement composites Edited by C L Page and M M Page Durability of composites for civil structural applications Edited by V M Karbhari Design and optimization of metal structures J Farkas and K Jarmai Developments in the formulation and reinforcement of concrete Edited by S Mindess Strengthening and rehabilitation of civil infrastructures using fibre-reinforced polymer (FRP) composites Edited by L C Hollaway and J C Teng Condition assessment of aged structures Edited by J K Paik and R M Melchers Sustainability of construction materials J Khatib Structural dynamics of earthquake engineering S Rajasekaran Geopolymers: Structures, processing, properties and industrial applications Edited by J L Provis and J S J van Deventer Structural health monitoring of civil infrastructure systems Edited by V M Karbhari and F Ansari Architectural glass to resist seismic and extreme climatic events Edited by R A Behr Failure, distress and repair of concrete structures Edited by N Delatte Blast protection of civil infrastructures and vehicles using composites Edited by N Uddin Non-destructive evaluation of reinforced concrete structures Volume 1: Deterioration processes Edited by C Maierhofer, H.-W Reinhardt and G Dobmann Non-destructive evaluation of reinforced concrete structures Volume 2: Nondestructive testing methods Edited by C Maierhofer, H.-W Reinhardt and G Dobmann Service life estimation and extension of civil engineering structures Edited by V M Karbhari and L S Lee Building decorative materials Edited by Y Li and S Ren Building materials in civil engineering Edited by H Zhang Polymer modified bitumen Edited by T McNally Understanding the rheology of concrete Edited by N Roussel Toxicity of building materials Edited by F Pacheco-Torgal, S Jalali and A Fucic 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 Woodhead Publishing Series in Civil and Structural Engineering 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 xiii Eco-efficient concrete Edited by F Pacheco-Torgal, S Jalali, J Labrincha and V M John Nanotechnology in eco-efficient construction Edited by F Pacheco-Torgal, M V Diamanti, A Nazari and C Goran-Granqvist Handbook of seismic risk analysis and management of civil infrastructure systems Edited by F Tesfamariam and K Goda Developments in fiber-reinforced polymer (FRP) composites for civil engineering Edited by N Uddin Advanced fibre-reinforced polymer (FRP) composites for structural applications Edited by J Bai Handbook of recycled concrete and demolition waste Edited by F Pacheco-Torgal, V W Y Tam, J A Labrincha, Y Ding and J de Brito Understanding the tensile properties of concrete Edited by J Weerheijm Eco-efficient construction and building materials: Life cycle assessment (LCA), eco-labelling and case studies Edited by F Pacheco-Torgal, L F Cabeza, J Labrincha and A de Magalh~ aes Advanced composites in bridge construction and repair Edited by Y J Kim Rehabilitation of metallic civil infrastructure using fiber-reinforced polymer (FRP) composites Edited by V Karbhari Rehabilitation of pipelines using fiber-reinforced polymer (FRP) composites Edited by V Karbhari Transport properties of concrete: Measurement and applications P A Claisse Handbook of alkali-activated cements, mortars and concretes F Pacheco-Torgal, J A Labrincha, C Leonelli, A Palomo and P Chindaprasirt Eco-efficient masonry bricks and blocks: Design, properties and durability F Pacheco-Torgal, P B Lourenỗo, J A Labrincha, S Kumar and P Chindaprasirt Advances in asphalt materials: Road and pavement construction Edited by S.-C Huang and H Di Benedetto Acoustic emission (AE) and related non-destructive evaluation (NDE) techniques in the fracture mechanics of concrete: Fundamentals and applications Edited by M Ohtsu Nonconventional and vernacular construction materials: Characterisation, properties and applications Edited by K A Harries and B Sharma Science and technology of concrete admixtures Edited by P.-C Aïtcin and R J Flatt Textile fibre composites in civil engineering Edited by T Triantafillou Corrosion of steel in concrete structures Edited by A Poursaee Innovative developments of advanced multifunctional nanocomposites in civil and structural engineering Edited by K J Loh and S Nagarajaiah Biopolymers and biotech admixtures for eco-efficient construction materials Edited by F Pacheco-Torgal, V Ivanov, N Karak and H Jonkers xiv Woodhead Publishing Series in Civil and Structural Engineering 64 Marine concrete structures: Design, durability and performance Edited by M Alexander Recent trends in cold-formed steel construction Edited by C Yu Start-up creation: The smart eco-efficient built environment F Pacheco-Torgal, E Rasmussen, C G Granqvist, V Ivanov, A Kaklauskas and S Makonin Characteristics and uses of steel slag in building construction I Barisic, I Netinger, A Fucic and S Bansode The utilization of slag in civil infrastructure construction G Wang 65 66 67 68 Preface This book presents a collection of frontier research results and the latest code developments in cold-formed steel (CFS) applications in buildings The content covers a large spectrum of knowledge: from basic design methodology to advanced computational modeling techniques, from structural behavior to the mechanical performance of CFS structures, and much more CFS has a long history of building applications, and in recent decades computerassisted fabrication technologies have helped CFS to become an alternative material for load-bearing structures in low- and mid-rise constructions The wide variety of cross-section shapes, connection details, and assembly configurations make CFS a big challenge for structural design but also a great opportunity for construction industries, as the nature of CFS enables them to pursue endless optimal solutions Innovation keeps driving CFS to be more efficient, more sustainable, and more accessible I hope this book will give readers a comprehensive introduction to the latest technical developments from the CFS research community I am thankful to the chapter authors who have made this book possible We have a world-class team of experts in CFS research Ten years hence the content of this book may no longer be at the cutting edge, but readers can always rely on our authors to present the latest trends in CFS construction Cheng Yu May 15, 2016 Denton, Texas Introduction to recent trends in cold-formed steel construction L.W Williams Steel Framing Industry Association Falls Church, VA, United States Cold-formed steel (CFS) as we know it today is one of the newest structural systems used in residential and nonresidential construction, but in a few short decades has grown into one of the most commonly used materials in developed economies around the world Countries experiencing rapid economic and industrial development, including China (Fig 1.1), India, and throughout the Middle East, South America, and Africa, are increasingly looking to CFS because it allows builders to erect new homes (Fig 1.2) and offices (Fig 1.3) in a fraction of the time compared with traditional construction materials 1.1 The history of cold-formed steel The use of CFS as a construction material dates back into the 1800s, although in shapes and dimensions that are quite unlike the typical framing members we see today Corrugated iron makers started using mild steel in the 1890s, and when cold-rolled and hotdipped galvanized it became an ideal cladding and structural sheathing for a wide range of building types in a variety of conditions and climates around the world The transition to the current shapes and applications for steel in construction followed the revolutionary change that occurred when builders recognized that the heavy timber commonly used for building frames could be replaced by smaller closely (a) (b) Figure 1.1(a,b) Cold-formed steel construction methods in China (shown here) follow the same general principles as in all other countries around the world Recent Trends in Cold-Formed Steel Construction http://dx.doi.org/10.1016/B978-0-08-100160-8.00001-3 Copyright © 2016 Elsevier Ltd All rights reserved 300 Recent Trends in Cold-Formed Steel Construction Figure 13.40 Site test results versus NLFEA shell model after Johnston et al (2015a): (a) finite element model of the building prior to collapse (predicted temperature of 704 C); (b) collapse of the building (recorded temperature of 714 C) Johnston, R.P.D., Lim, J.B.P., Lau, H.H., Xu, Y., Sonebi, M., Armstrong, C.G., Mei, C.C., 2015 FE investigation of cold-formed steel portal frames in fire Proceedings of the ICE e Structures and Buildings [Online] Johnston et al (2015b) also recommended that different fire scenarios be considered by designers to ensure a conservative approach Nonlinear elastoplastic shell models demonstrated a good agreement with physical testing, more so than beam models, and may therefore be used to predict the response of CFS portal frames subject to fire (see Fig 13.40) SCI P313 guidance for hot-rolled steel portal frames should not be used for CFS portal frames in fire boundary conditions The results from experimental and nonlinear finite element analysis (NLFEA) testing at elevated temperatures by Johnston et al (2014), and Johnston et al (2015a,b) concluded the following • The secondary structural elements had a beneficial effect on the behavior of CFS portal frames in fire, in terms of giving a higher failure temperature and preventing undesirable collapse mechanisms in fire Adequate provision should be made where the continuity of secondary members is broken up to facilitate openings Sustainable applications of cold-formed steel structures: portal frames • • • • 301 Base fixity influences the collapse mode and failure temperature However, the fixity would need to be accurately quantified for CFS portal frames due to the pinned or partial rigidity of base connections In lieu of necessary research, it was recommended that the side-rails, columns, and associated connections to columns and fire-rated cladding are suitably protected along their entire length NLFEA shell models were validated against site test results, and therefore can be used to assist designers in predicting the behavior of CFS portal frames in fire A like-for-like 22 m span CFS alternative to the hot-rolled steel portal frame example presented in the SCI P313 design guidance failed with an asymmetric collapse mechanism at a temperature of 595e601 C, depending on the base condition This is comparable to the failure temperature of 890 C specified for the 22 m span hot-rolled frame in the SCI guidance Results demonstrated that without the inclusion of in-plane restraint, the 22 m CFS frame with fully pinned bases failed with an undesirable outward sway collapse mechanism at 595 C Although not representative of a real fire, the ISO (International Organization for Standardization) standard curve is commonly used in practice Therefore, based on the difference in collapse temperature, it is recommended that practicing engineers consider the difference in the time domain for collapse in fire The use of the SCI P313 guidance document for the design of single-story hot-rolled portal frames in fire boundary condition is potentially unconservative for CFS portal frames Design recommendations and a simplified mathematical model are presented in Johnston (2015) 13.6 Conclusions This chapter reviews different arrangements in bolted-moment connections between CFS members As can be seen, almost all the joints comprise channel sections for the members, connected through gusset plates bolted to the webs of the channel sections The general arrangement involves a bolt group in a regular grid with each bolt passing through the webs of the channel sections Variations to this arrangement include connections with bolts through the flanges of the channel sections, or more bolts located away from the center of rotation of the bolt group Using a general joint arrangement comprising a  array of bolts, a method for determining the rotational stiffness of the joints is described, which can then be incorporated into a frame analysis In some cases, semirigid joints of finite connection lengths having a practical joint detail can actually result in a frame with a higher load-carrying capacity than an equivalent rigidly jointed frame Full-scale frame tests have demonstrated the accuracy of the beam idealization for a bare frame of 12 m span Full-scale building tests are also described, conducted to investigate the effect of roof sheeting for small-span buildings It is shown that stressed-skin diaphragm action is important to consider, particularly if the objective is to prevent tearing of cladding at serviceable loads Finally, fire design criteria for such buildings are considered As can be seen, the structural system maintains stability and is stronger than the sum of its individual components A fire-protected lower side-rail is recommended to improve the stability of the system, specifically the stability of the collapsing walls in fire 302 Recent Trends in Cold-Formed Steel Construction References Baigent, A.H., Hancock, G.J., 1978 The Behaviour of Portal Frames Composed of Cold-formed Members University of Sydney, School of Civil Engineering, Sydney Baigent, A.H., Hancock, G.J., 1982 Structural analysis of assemblages of thin-walled members Engineering Structures 4, 207e216 Bryan, E.R., 1993 The design of bolted joints in cold-formed steel sections Thin-walled Structures 16, 239e262 BS 5950-5, 1998 Structural Use of Steelwork in Building Part 5: Code of Practice for Design of Cold Formed Thin Gauge Sections British Standards Institution, London BS EN 1993-1e8, 2005 Eurocode 3-Design of Steel Structures Part 1-8: Design of Joints European Committee for Standardization, Brussels Chung, K.F., Lau, L., 1999 Experimental investigation on bolted moment connections among cold formed steel members Engineering Structures 21, 898e911 Crawford, S.F., Kulak, G.L., 1971 Eccentrically loaded bolted connections Journal of the Structural Division, ASCE 97, 765e783 Dubina, D., Stratan, A., Ciutina, A., Fulop, L., Zsolt, N., 2004 Monotonic and cyclic performance of joints of cold formed steel portal frames Loughborough, UK In: Loughlan, J (Ed.), 4th International Conference on Thin-walled Structures, pp 381e388 Dundu, M., Kemp, A.R., 2006 Plastic and lateral-torsional buckling behaviour of single cold-formed channels connected back-to-back Journal of Structural Engineering 132, 1223e1233 Hancock, G.J., 1985 Portal frames composed of cold-formed channel-sections In: Narayanan, R (Ed.), Chapter 8, Steel Framed Structures Elsevier Applied Science Publishers, London Johnston, R.P.D., Lim, J.B.P., Lau, H.H., Xu, Y., Sonebi, M., Armstrong, C.G., Mei, C.C., 2015a FE investigation of cold-formed steel portal frames in fire Proceedings of the ICE e Structures and Buildings [Online] Available: http://www.icevirtuallibrary.com/content/ article/10.1680/stbu.14.00082 Johnston, R.P.D., Lim, J.B.P., Lau, H.H., Xu, Y., Sonebi, M., Armstrong, C.G., Switzer, C., Mei, C.C., 2014 Cold-formed steel portal frames in fire: full-scale testing and finite element analysis [Online] The Structural Engineer 92 Johnston, R.P.D., Sonebi, M., Lim, J.B.P., Armstrong, C.G., Wrzesien, A.M., Abdelal, G., Hu, Y., 2015b The collapse behaviour of cold-formed steel portal frames at elevated temperatures Journal of Structural Fire Engineering 6, 77e101 Kirk, P., 1986 Design of a cold formed section portal frame building system St Louis, Missouri, USA In: 8th International Specialty Conference on Cold-formed Steel Structures, pp 295e310 Kwon, Y.B., Chung, H.S., Kim, G.D., 2006 Experiments of cold-formed steel connections and portal frames Journal of Structural Engineering 132, 600e607 Lim, J.B.P., Hancock, G.J., Charles Clifton, G., Pham, C.H., Das, R., 2016 DSM for ultimate strength of bolted moment-connections between cold-formed steel channel members Journal of Constructional Steel Research 117, 196e203 Lim, J.B.P., Nethercot, D.A., 2002 F E.-assisted design of the eaves bracket of a cold-formed steel portal frame Steel & Composite Structures 2, 411e428 Lim, J.B.P., Nethercot, D.A., 2003a Serviceability design of a cold-formed steel portal frame having semi-rigid joints Steel & Composite Structures 3, 451e474 Lim, J.B.P., Nethercot, D.A., 2003b Ultimate strength of bolted moment-connections between cold-formed steel members Thin Walled Structures 41, 1019e1039 Sustainable applications of cold-formed steel structures: portal frames 303 Lim, J.B.P., Nethercot, D.A., 2004a Finite element idealization of a cold-formed steel portal frame Journal of Structural Engineering 130, 78e94 Lim, J.B.P., Nethercot, D.A., 2004b Stiffness prediction for bolted moment-connections between cold-formed steel members Journal of Constructional Steel Research 60, 85e107 M€akel€ainen, P., Kankaanp€a€a, J., 1996 Structural design study on a light-gauge steel portal frame with cold-formed sigma sections St Louis, Missouri, USA In: 13th International Specialty Conference on Cold-formed Steel Structures, pp 349e371 Mills, J., LaBoube, R., 2004 Self-drilling screw joints for cold-formed channel portal frames Journal of Structural Engineering 130, 1799e1806 Phan, D.T., Lim, J.B.P., Tanyimboh, T.T., Wrzesien, A.M., Sha, W., Lawson, R.M., 2015 Optimal design of cold-formed steel portal frames for stressed-skin action using genetic algorithm Engineering Structures 93, 36e49 Rhodes, J., Burns, R., 2006 Development of a portal frame system on the basis of component testing In: 18th International Specialty Conference in Cold-formed Steel Structures (Orlando, Florida, USA) SCI P313, 2002 In: Simms, W.I., Newman, G.M (Eds.), Single Storey Steel Framed Buildings in Fire Boundary Conditions The Steel Construction Institute, Ascot, UK Vlasov, V.Z., 1961 Thin-walled Elastic Beams Israel Program for Scientific Translation, Jerusalem Wong, M.F., Chung, K.F., 2002 Structural behaviour of bolted moment connections in coldformed steel beam-column sub-frames Journal of Constructional Steel Research 58, 253e274 Wrzesien, A.M., Lim, J.B.P., Lawson, R.M., 2009 The ultimate strength and stiffness of modern roof systems with hat-shaped purlins Hong Kong, China In: Chan, S.L (Ed.), Sixth International Conference on Advances in Steel Structures, pp 480e487 Wrzesien, A.M., Lim, J.B.P., Xu, Y., Dundu, M., Macleod, I., Lawson, R.M., 2012 Stressed skin effects on cold-formed steel portal frames with semi-rigid joints e experimental study In: The 6th International Conference on Coupled Instabilities in Metal Structures (Glasgow, UK) Wrzesien, A.M., Lim, J.B.P., Xu, Y., Macleod, I.A., Lawson, R.M., 2015 Effect of stressed skin action on the behaviour of cold-formed steel portal frames Engineering Structures 105, 123e136 Yu, W.K., Chung, K.F., Wong, M.F., 2005 Analysis of bolted moment connections in coldformed steel beamecolumn sub-frames Journal of Constructional Steel Research 61, 1332e1352 Zadanfarrokh, F., Bryan, E.R., 1992 Testing and design of bolted connections in cold-formed steel sections St Louis, Missouri, USA In: 11th International Specialty Conference on Cold-formed Steel Structures, pp 625e662 Zaharia, R., Dubina, D., 2006 Stiffness of joints in bolted connected cold-formed steel trusses Journal of Constructional Steel Research 62, 240e249 Zbirohowski-Koscia, K., 1967 Thin-walled Beams e From Theory to Practice Crosby Lockwood, London Index ‘Note: Page numbers followed by “f” indicate figures, “t” indicate tables.’ A ABAQUS models, 235 ABC algorithm See Artificial bee colony algorithm (ABC algorithm) Acceptability criteria classification for floor vibration, 186e192 and design method for CFS floors, 187e192 floor cross-section, 189f ACO algorithm See Ant colony optimization algorithm (ACO algorithm) Acoustic performance of CFS buildings, 173 See also Floor vibration in CFS buildings; Structural optimization of CFS structures acoustic insulation performance requirements, 175e176 building design for acoustic performance, 176e177 design examples, 179e181 floating floor with metal joists and resilient metal bars, 180f sound transmission paths between two rooms, 176f staggered studs, absorptive materials, and resilient metal bars, 180f tests, performance tables, and insulation values, 177e179 Airborne sound insulation, 174 AISI See American Iron and Steel Institute (AISI) AISI S100, 39e45 AISI S220e15 North American cold-formed steel framing standard, 47e48 North American standard for cold-formed steel structural framing, 48 North American standard for seismic design of cold-formed steel structural systems, 49 AISI/Committee on Framing Standards (USA), Algorithms for design optimization of CFS framing structures, 132 ACO algorithm, 140 ANN, 138e140 GA, 132e135, 139f SA, 135e138, 137f American Iron and Steel Institute (AISI), 4e5, 39, 53e54, 130, 183 ASD specification, 130e131 CFS specification, 4e5, 6f “Cold-Formed Steel Design Manual”, 54 compression design of load-bearing clip angle connectors, 64e66 failure mechanism of steel-sheet-sheathed shear walls, 55f shear design of load-bearing clip angle connectors, 62e64 sheet steel shear wall design, 56e62 up-to-date design examples, 54 American National Standards (ANS), 39 American Society for Testing Materials (ASTM), 22, 40, 225 steel specifications for high-strength steel, 225 American Society of Civil Engineers (ASCE), 204 Analytical formulae or models, 110 ANN See Artificial neural network (ANN) ANS See American National Standards (ANS) Ant colony optimization algorithm (ACO algorithm), 131e132, 140 Apex brackets, 285t 306 Applied Technologies Council (ATC), 186e187 Armco-Ferro house, 3, 4f Artificial bee colony algorithm (ABC algorithm), 140 Artificial neural network (ANN), 138e140 ASCE See American Society of Civil Engineers (ASCE) ASTM See American Society for Testing Materials (ASTM) ATC See Applied Technologies Council (ATC) Australian and international markets, shapes in, 221e222 Australian steel standard AS1397, 224e225 Automated design integrating computational elastic buckling analysis, 122e123 Automated roll former, 13e14, 14f B Back-to-back brackets, 271e274 Bar joists, CFS with, 30f Bare frames, 278e279 See also Clad frames; Frame idealization analytical formulae for predicting elongation stiffness, 280t back-to-back channel sections, 285f beam idealization, 281e283 bending moment distribution, 279f bimoment effect, 283e286 bolt group resisting moment, 280f semirigid joints, 281e283 structural design, 279 “Base curve”, 72 BBO See Biogeography-based optimization algorithm (BBO) Beams, 78e81, 79fe80f Beam-to-column joints, 253, 254t idealization, 281e283, 290 Bearing factor, 42e44, 43t Bending, 41 Bending behavior and design, 226 DSM design for flexure, plastic behavior, 226 flexural testing of plain C-sections and SupaCee sections, 227e231 inelastic reserve strength, 227 Bending moments, joint effects on, 290e293 Index Bimoment effect, 283e286 Biogeography-based optimization algorithm (BBO), 144e145 Blast furnace, 12, 12f generators, 211 simulator system, 211 wall tests, 211 wave design parameters, 203e204 effects on buildings, 203 Blast resistance of CFS buildings, 203 analysis and design methods, 213 design of connections, 215e216 dynamic design approach, 214e215 equivalent static loads for roof trusses, 215 static design approach, 213e214 blast wave design parameters, 203e204 blast wave effects on buildings, 203 codes and standards, 204 dynamic modeling and performance criteria, 205e208 test studies, 208 blast simulator wall tests, 211 connection tests, 212 full-scale wall tests, 209e211 “Bobby pin”, 143 Bolted connections, 42e44 Bolts/bottom track, 33, 34f Boundary conditions, 111 Bracing of axially loaded compression members, 41e42 Brackets, 270e271, 281 Buckling analysis, 222e223 Building design for acoustic performance, 176e177 Bundled panels, 15f C C-shape stiffening member, 197 Canadian Construction Materials Center, 187 Canadian Standards Association (CSA), 204 CFS See Cold-formed steel (CFS) cFS See Constrained finite strip (cFS) CFSEI See Cold-Formed Steel Engineers Institute (CFSEI) Index cFSM See constrained FSM (cFSM) Clad frames See also Bare frames; Frame idealization test results, 294e298 tests, 294 Classic beam theory, 110 Classical design procedure, 130 Closed-form solutions, 109e110 Coating designations, 22 Codes and standards, 204 Coil, 12, 13f Cold-formed steel (CFS), 1, 12e24, 39, 53, 69, 109, 130, 155, 183 advantages, 24e26 AISI CFS specification, 4e5, 6f buildings, 203 C-shape joists, 192 coating designations, 22 column strength to thermal gradient, 167e168 at uniform elevated temperature, 165e167 and commercial market, 7e9 construction methods, 1fe2f, 29e33 corrosion resistance, 20e22 designator systems, 19e20, 20f EQ coatings, 22e23 EQ studs, 19, 19f framing exterior/load-bearing/structural wall systems, 26e27 floors and roofs, 27e29 hybrid systems, 29 interior partition, 26f interior/nonbearing/nonstructural wall systems, 26 midrise building, 20f shapes, 15e19 history, 1e12 installing continuous insulation, 23f Living Steel global project, 9e12 physical dimensions, 15 portal frames, 266e267 advantages, 267 bare frames, 278e286 bolted joints, 275f clad frames, 294e298 eaves joint, 270f, 272fe274f, 276f fire design, 298e301 307 frame idealization, 286e294 joint eaves and apex joints, 277f joints in literature, 268te269t literature review, 267e278 outline, 278 portal framing system, 266f summary of literature, 278 Swagebeam eaves joint, 271f postwar boom, 5e7 residential market, revisions of AISI cold-formed steel framing standards AISI S220e15, North American coldformed steel framing standard, 47e48 AISI S240e15, North American standard for cold-formed steel structural framing, 48 AISI S400e15, North American standard for seismic design of coldformed steel structural systems, 49 conversion of ASCE to AISI S230 basic wind speeds, 47t technical changes in AISI S214e12, 46 technical changes in S200e12, 45e46 technical changes in supplement to AISI S211e07, 47 technical changes in supplements and to AISI S230e07, 47 revisions of AISI S100, North American specification for design of mapping of AISI S100e07 to new AISI S100e16, 46t maximum size of bolt holes, 42t reorganized AISI S100e16, 45 technical changes and additions in AISI S100e12, 39e45 structures, 241 studs, 173, 177 thermal conductivity, 23e24 “Cold-Formed Steel Design Manual”, 53e54 Cold-Formed Steel Engineers Institute (CFSEI), 54 Cold-reduced high-strength steel standards and specifications ASTM steel specifications for high-strength steel, 225 Australian steel standard AS1397, 224e225 308 Cold-rolled channel, 17f “Cold-rolled steel”, 12 Columns, 76e78, 77f Combined bending-shear strength, 84e85 Compression design of load-bearing clip angle connectors, 64e66 See also Shear design of load-bearing clip angle connectors compression design method, 64e65 design example, 65e66 theoretical k values, 65t Computational modeling, 109, 111e112 Connection brackets, 275 design, 215e216 methods, 33, 55 bolts/bottom track, 34f screws, 33f welds, 33f strength, 25 tests, 212 Consistent performance, 25 Constrained finite strip (cFS), 74e75 constrained FSM (cFSM), 111, 118e119 mechanical criteria of mode definition, 118t modal decomposition, 118 modal identification, 119 Construction details effect on floor vibration, 192e198 See also Vibration performance evaluation bridging and blocking effect, 196e197 ceiling and gluing subfloor effect, 196 discussion and comparison of results between laboratory and in situ tests, 193e195 floor framing conditions effect, 195 floor transverse deflection distribution, 194f joist-end reaction distribution, 194f nonload-bearing partition wall effect, 197e198 screw spacing effect, 197 strongback effect, 197e198 subfloor sheathing material and topping effect, 195e196 Construction methods, 29e33 connection methods, 33 panelization, 31e32 Continuous strength method (CSM), 72 Conventional framing See Rafter framing Index Corner radius-to-thickness ratios, 40, 41f Corrosion resistance, 20e22 Galvanic series, 21f spangle typical of galvanized coating, 21f Critical buckling loads/moments determination, 73e76 Cross-section analysis, 116e117 CSA See Canadian Standards Association (CSA); Cuckoo search algorithm (CSA) CSM See Continuous strength method (CSM) Cuckoo search algorithm (CSA), 144e145 CUFSM program, 113e114, 120e121, 131e132 CUTWP open source software, 119e120 D Damage, 203, 205, 207 expected component, 207t patterns, 212 Deconstruction, 244e245 connections and joints for considerations for creating novel connections, 254e255 future trends, 255e256 Demolition, 244e245 Design charts, 286 Design for deconstruction (DfD), 243e245 Designator systems, 19e20, 20f DfD See Design for deconstruction (DfD) DeG interaction See Distortionaleglobal interaction (DeG interaction) DIF See Dynamic increase factor (DIF) Dimension optimization, 129 Direct strength method (DSM), 40, 69, 70f, 121, 130, 164e165, 221 See also Shear behavior and design advances and future developments in DSM-based CFS design, 89e98 basic idea and origin, 69e71 design for flexure, plastic behavior distortional buckling strength, 226 local buckling strength, 226 first-generation codified DSM design curves, 73e81 historical perspective, 71e72 second-generation codified DSM design curves, 81e89 Index Disassembly, 244e245 Distortional buckling, 69, 87f empirical formulae for distortional buckling stress, 110 interactive failures involving, 90e91 strength, 226 Distortionaleglobal interaction (DeG interaction), 90 DSM See Direct strength method (DSM) DSM-based cold-formed steel design columns and beams under elevated temperatures, 92e94 equal-leg angle columns, 91e92 interactive failures involving distortional buckling, 90e91 members under compression and bending, 96e98 recent advances and future developments in, 89e98 structural systems, 98 web crippling, 94e96, 95f Duality theory, 132e133 Ductility ratio, 207e208 Dynamic design approach, 214e215 Dynamic increase factor (DIF), 206 Dynamic material properties, 206 Dynamic modeling and performance criteria, 205 dynamic material properties, 206 performance criteria, 206e208 resistance function, 205e206 response limits, 206e208 E Earth’s gravity, 192 Eaves joint, 270f Effective composite bending stiffness, 188 Effective number of joists, 190 Effective section approach, 71 Effective strip method, 56e58, 57f Effective width at edge stiffener, 40, 41f Effective width method (EWM), 69, 164 EIFS See Exterior insulation finish system (EIFS) 800S162e54 flange, 20 Elastic buckling analysis, 70, 117 analytical formulae or models, 110 applications in design and development, 121e125 309 automated design integrating computational elastic buckling analysis, 122e123 design example employing numerical elastic buckling solutions, 121e122 modal identification for shell finite element method, 123e125 closed-form solutions, 109e110 numerical solution methods for, 111e119 open source programs and other software packages, 119e121 sources of further information and advice, 125 Elastic modulus, 161 Electric arc furnace See Oxygen furnace Elevated temperatures, columns and beams under, 92e94 Emissions, 25 End one flange (EOF), 94 End two flange (ETF), 94 Energy, 25 EOF See End one flange (EOF) EQ coatings See Equivalent coatings (EQ coatings) Equal-leg angle columns, 91e92 Equivalent coatings (EQ coatings), 22e23 Equivalent static loads for roof trusses, 215 Equivalent studs (EQ studs), 19, 19f ETF See End two flange (ETF) Euler buckling formula, 110 EWM See Effective width method (EWM) Explicit critical loads of global buckling, 110 Exterior insulation finish system (EIFS), 209e210 F Federal Emergency Management Agency (FEMA), 204 FEM See Finite element method (FEM) FEMA See Federal Emergency Management Agency (FEMA) FFA See Firefly algorithm (FFA) Finite element method (FEM), 110e113, 121, 124, 178, 179f, 221e222 limitations, 112e113 modeling sensitivity, 111e112, 112f shell FEM formulation, 111 Finite element modeling of test rig, 234e235 310 Finite strip method (FSM), 110, 113e116 in other forms, 116 semianalytical FSM, 113e115 shell FEM vs FSM mesh, 113f signature curve, 114f Spline finite strip method, 115 Fire design, 298e301 Firefly algorithm (FFA), 144e145 “First generation of DSM design curves”, 71 First-generation codified DSM design curves, 73e81 See also Secondgeneration codified DSM design curves beams, 78e81, 79fe80f columns, 76e78, 77f critical buckling loads/moments determination, 73e76 lipped channel column, 75f prequalification, 73, 74f Flexural members, 42 Flexural testing of plain C-sections and SupaCee sections, 227e231 Flexure, DSM design for, 226 Floor vibration in CFS buildings, 183 See also Acoustic performance of CFS buildings; Structural optimization of CFS structures construction details effect, 192e198 designing CFS floor system, 183 vibration performance evaluation, 184e192 Floor(s), 27e29 construction, 180 stiffness, 198e199 Formosan subterranean termite, 9, 11f Frame idealization beam idealization for frame, 290 full-scale tests, 293e294 full-scale tests, 286e290 joint effects on bending moments, 290e293 Free warping, 81 FSM See Finite strip method (FSM) FSM@cFSM-Lcr, 123 Full-scale tests, 286e290, 293e295, 295f wall tests, 209e211 Fundamental frequency of one-way floor structure, 190e191 Furring channel See Hat channel Index G GA See Gradient-based algorithm (GA) Galvanic series, 21f GBT See Generalized beam theory (GBT) GBT at the University of Lisbon (GBTUL), 120 Generalized beam theory (GBT), 74e75, 110, 116e117 cross-section analysis, 116e117 elastic buckling analysis, 117 in-plane shapes, 117f Geometric nonlinearity, 111 Global buckling, 69, 87f Global stability, 110 Good Housekeeping/Stran-steel house, 3, 4fe5f Gradient-based algorithm (GA), 131e138, 142e143 H Harmonic coupled FSM, 115 Hat channel, 17, 18f Heat transfer numerical models, 155e157 High-strength steels and design standards and specifications, 221 Hollow flange channel beams, 95e96 Hollow-core plank, 28f “Hot band”, 12 Human perceptibility classification to floor vibrations, 184e185 Human walking, 183e184, 186, 198e199 Hybrid systems, 29 I IIC See Impact Insulation Class (IIC) IISI See International Iron and Steel Institute (IISI) Impact Insulation Class (IIC), 176 Impact sound, 174 Inelastic reserve strength, 227 Integrated life-cycle design of sustainable CFS structures, 244f methods for sustainable CFS structures, 243 process, 241e242 service life of CFS building products, 242e243 sustainable requirements and functional descriptions, 242 Internal one flange (IOF), 94 Index Internal two flange (ITF), 94 International Iron and Steel Institute (IISI), 9, 25 International Organization for Standardization (ISO), 185 acceleration limits, 186f IOF See Internal one flange (IOF) ISO See International Organization for Standardization (ISO) ITF See Internal two flange (ITF) J Joining methods in 1D and 2D components prefabrication, 257e259 in assembling CFS modules, 259e261 Joint effects on bending moments, 290e293 “Joists”, 15e16, 17f K KarusheKuhneTucker conditions (KKT conditions), 132e133 L L-header, 17, 18f Laser beam welding technologies (LBW technologies), 257 Lateral load resistance, 24e25 Layering concept, 245e246, 253e254 LBW technologies See Laser beam welding technologies (LBW technologies) LeD interaction See Localedistortional interaction (LeD interaction) LeDeG interaction See Localedistortionaleglobal interaction (LeDeG interaction) Ledger framing, 195 Level of protection (LOP), 206e207 LeG interactive failures See Localeglobal interactive failures (LeG interactive failures) Light frame systems, 24e26 “Light Gage Steel Design Manual”, 53e54 Light Gauge Steel Engineers Association (USA), Lightweight floor, 183, 187, 192, 195 Lightweight staggered steel stud double walls, 174 Limit states design, 44 311 Lipped channel column, 75f, 87f section, 141, 141f Living Steel global project, 9e12 House on hill in Hawaii, 11f House01eTurkey, 10f Styltech, 10f Load and resistance factor design, 44 Load-bearing clip angle connectors compression design of, 64e66 shear design of, 62e64 Local buckling, 69, 87f strength, 226 Localedistortional interaction (LeD interaction), 90 Localedistortionaleglobal interaction (LeDeG interaction), 90 Localeglobal interactive failures (LeG interactive failures), 76e77 Long span, 29f Long-established effective width method, 130 LOP See Level of protection (LOP) Low-frequency floors, 186e187 M Material recycling, 249 Maximum floor deflection, 187e188 Mechanical properties, 158e161 “Mils”, 15 Modal decomposition, 118, 120f Modal identification, 119, 120f for shell finite element method, 123e125 Modeling sensitivity, 111e112, 112f Modification factor, 42e44, 43t Modified ReihereMeister scale, 184e185, 185f Modular construction, 243e245, 256e257 Modular-unit-assembled buildings, 260 Mold-proof, 25e26 Monolithic concrete walls, 174 Multiobjective optimization problems, 129 Multipliers, 185 N Nailable stud, 7e8, 8f National Association of Steel Housing (Australia and New Zealand), National Building Code of Canada, 187 312 NLFEA See Nonlinear finite element analysis (NLFEA) Noncombustible structures, 25 Nonlinear finite element analysis (NLFEA), 300e301 Nonstructural member, 47e48 Novel/modified NLD approach, 90 Numerical models of heat transfer, 155e157 Numerical solution methods for elastic buckling analysis, 111e119 cFSM, 118e119 FEM, 111e113 FSM, 113e116 GBT, 116e117 O Objective function evaluation, 129, 132e133 Open source programs and other software packages, 119e121 CUFSM, 120e121 CUTWP, 119e120 finite element method, 121 GBTUL, 120 “Overall interaction concept”, 72 Oxygen furnace, 12 P Panel absorbers, 175 Panelization, 31e32 panel being lifted into place, 33f panel tables, 32f panels on job site, 32f Panelized components, 31 Parallel buckling phenomena, 109 Partition walls double-leaf, 173, 176, 178e179 single-leaf, 176 two-dimensional FE model, 179f Patch loading, 94 PDC See US Protective Design Center (PDC) Peak pressure, 203 Peak reflected pressure, 203 Perforated members, 85e86, 85f Performance criteria, 206e208 Plain C-sections flexural testing, 227e231 Plastic behavior, DSM design for, 226 Porous materials, 175 Index Postwar boom, 5e7 Lustron home on trailer, 6f Original Lustron home, 7f Preengineered system, 29e31 Prefabricated production, connections and joints for joining methods in 1D and 2D components prefabrication, 257e259 joining methods in assembling CFS modules, 259e261 Prequalification, 73, 74f Prequalified members, 73 Press joining, 258e259 Prevented warping, 81 Product reuse, 249 Pull-out, 44 Punched window, 213 Q Quantitative methods, 249 QuiconÒ connection, 256, 257f R Rafter framing, 27 Rational engineering analysis method, 40 Raw steel, 12 Recommended solution, 123f Recycling, 25 Reduction factor, 41 ReihereMeister scale, 184e185 Resistance function, 205e206 Resource extractions, 241e242 Response limits, 206e208 Retention factors, 161 “Rim joist”, 15e16 RMS acceleration See Root mean squared acceleration (RMS acceleration) Roll forming, 12, 14f Roofs, 27e29 Root mean squared acceleration (RMS acceleration), 185 ROSETTE technology, 257e258 Rrefabrication, 256e257 S SA See Stochastic search algorithm (SA) SCI See Steel Construction Institute (SCI) Screws, 33, 33f Index SD method See Steepest descent method (SD method) SDOF system See Single-degree-offreedom system (SDOF system) Second-generation codified DSM design curves, 81e89 See also Firstgeneration codified DSM design curves combined bending-shear strength, 84e85 DSM distortional design curves for columns with holes, 88f interaction diagrams for beams, 84f member with holes, 85e89 shear strength, 82e83 Secondary bifurcation interaction, 90e91 Self-drilling screws, 273 Self-shape optimization, 131e132 Semianalytical FSM, 113e115 Semirigid joints, 281e283 Sequential quadratic programming (SQP), 130e131, 134e135 SFE See Shell finite element (SFE) SFSM See Spline finite strip method (SFSM) Shape functions, 113 Shape memory alloys (SMAs), 255e256 Shape optimization of CFS members, 140e143 design performance comparisons, 146t design variables of constrained shape optimization, 142f lipped channel section and design variables of unconstrained optimization, 141f optimized cross-sections, 143fe145f Shapes, innovative in Australian and international markets, 221e222 bending behavior and design, 226e231 buckling analysis, 222e223 cold-reduced high-strength steel standards and specifications, 224e225 high-strength steels and design standards and specifications, 221 shear behavior and design, 231e238 signature curves, 222e223 Shear, 44 strength, 82e83 Shear and transverse extension (ST extension), 118 313 Shear behavior and design, 231 comparison with DSM design equations for shear, 235e236 with existing DSM design specification, 236e238 DSM design rules for combined bending and shear, 232 without tension field action, 231e232 with tension field action, 232 FE modeling of test rig, 234e235 stiffened web channel, 234e235 testing of stiffened web channel sections, 233e234 Shear design of load-bearing clip angle connectors, 62e64 See also Compression design of load-bearing clip angle connectors design example, 63e64 shear strength with consideration of clip angle deformation, 63 shear strength without consideration of clip angle deformation, 62 Sheet steel shear wall design, 56e62 design example, 58e62 effective strip method, 56e58, 57f Shell FEM formulation, 111 Shell finite element (SFE), 74e75 Shock wave, 203 SIF See Static increase factor (SIF) Signature curve, 113e114, 114f Signature curves, 222e223 Single-degree-of-freedom system (SDOF system), 205e206, 214 Slenderness, 94e95 Slit coils, 12, 13f Slotted stud, 24f Smart materials, 255e256 SMAs See Shape memory alloys (SMAs) Sound, 173 insulation, 174 field measurements, 175 values, 173 pressure, 173 reduction index, 174 Sound Transmission Class (STC), 176 South African Steel Framing Association, Spline finite strip method (SFSM), 115, 232 314 SQP See Sequential quadratic programming (SQP) SSMA See Steel Stud Manufacturers Association (SSMA) ST extension See Shear and transverse extension (ST extension) Static design approach, 213e214 Static increase factor (SIF), 206 STC See Sound Transmission Class (STC) Steady-state tests, 160 Steel, 23 Steel Construction Institute (SCI), 180e181, 204, 267 Steel Framing Alliance (USA), Steel House Club (Korea), Steel Recycling Institute, 25 Steel Stud Manufacturers Association (SSMA), 113e114 Steel sustainability, 25 Steepest descent method (SD method), 130e131, 133 Step direction, 133 Stick building, 29 Stiffened web channel, 234e235 sections shear testing, 233e234 Stochastic search algorithm (SA), 131e132, 135e138, 137f, 142e143 Strength, 42e44 Strength-to-weight ratio, 25 Structural fire design, 163 Structural optimization of CFS structures, 129e132 See also Acoustic performance of CFS buildings; Floor vibration in CFS buildings algorithms for, 132e140 future research directions, 147e149 self-shape optimization, 131e132 shape optimization of CFS members, 140e143 system-level optimization of CFS framing structures, 144e145 Structural steel, CFS with, 30f Structural systems, 98 “Studs”, 15, 16f, 31f SupaCee sections flexural testing, 227e231 Support rotation, 207e208, 214e215 Sustainability of steel, 25 Sustainable applications of CFS structures Index integrated life-cycle design methods for sustainable CFS structures, 243 process, 241e242, 241f service life of CFS building products, 242e243 sustainable requirements and functional descriptions, 242 Sustainable connections and joints CFS connections and joints, 246 classification for sustainable performance, 246e247 classification of CFS connections, 247e249 for deconstruction considerations for creating novel connections, 254e255 future trends, 255e256 DfD, 243e245 modular construction, 243e245 performance of sustainability connections, 249 joints, 249e254 for prefabricated production, 256e257 joining methods in 1D and 2D components prefabrication, 257e259 joining methods in assembling CFS modules, 259e261 principles for ease of deconstruction, 245e246 System-level optimization of CFS framing structures, 144e145 1211-member lightweight CFS frame 3D view of, 147f optimum design results of, 147t search histories of, 148f T Teaching-learning-based optimization algorithm (TLBO), 144e145 Temperature-dependent CFS constitutive law model, 93e94 Temperature-dependent material properties, 157 Tension, 44 membrane, 205e206, 209e210 Tension field action (TFA), 232 Termite-proof, 25 TFA See Tension field action (TFA) Index Thermal conductivity, 23e24 Thermal performance of CFS structures in fire design examples of thermomechanical performance, 165e168 engineering-based analysis and design, 155 inclusion of thermal effects, 163 numerical models of heat transfer, 155e157 tests, analysis, and results, 163e165 thermomechanical performance of materials, 157 mechanical properties, 158e161 thermal properties, 157 Thermal properties, 157 Thermomechanical performance design examples, 165 strength of CFS column to thermal gradient, 167e168 at uniform elevated temperature, 165e167 Thermomechanical performance of materials, 157 mechanical properties, 158e161 thermal properties, 157 Thin-walled CFS clip angle, 55, 56f Three-dimensional stressed-skin analysis, 298 TLBO See Teaching-learning-based optimization algorithm (TLBO) Torsional loading, 41 Track, 15e16, 16f Transient-state test, 159e160 “True LeD interaction” effects, 90e91 Truss framing, 27e29 Trust region method, 134e135 U U-channel, 17 UFC See Unified Facilities Criteria (UFC) Uncomfortable vibration classification, 184e185 315 Unified Facilities Criteria (UFC), 204 Unlipped channel beams, 95e96 US National Association of Home Builders, 183 US Protective Design Center (PDC), 206e207 V Vertical loading, 294 Vibration performance evaluation, 184e192 See also Construction details effect on floor vibration acceptability criteria classification for floor vibration, 186e192 and design method for CFS floors, 187e192 human perceptibility classification to floor vibrations, 184e185 Virginia Baptist Hospital, 3, 3f W Wall systems exterior/load-bearing/structural, 26e27 midrise building, 20f interior/nonbearing/nonstructural, 26 interior partition, 26f Web crippling, 94e96, 95f strength, 41 Welds, 33, 33f Whitmore section width, 65 Wide-span trusses, 28f Width method, 285e286 “Winter-type” equations, 70 Winter’s expression/curve, 71 World Steel Association See International Iron and Steel Institute (IISI) Y Yield stresses, 70, 93e94 Young’s modulus, 93e94 ... Nonresidential Steel Framing Industry Association cfsteel.org Recent Trends in Cold-Formed Steel Construction Introduction to recent trends in cold-formed steel construction Figure 1.4 Virginia Baptist... structures in 36 states Figure 1.7 AISI CFS specification Figure 1.8(a) Lustron home on a trailer Recent Trends in Cold-Formed Steel Construction Introduction to recent trends in cold-formed steel construction. .. within buildings In 2004 the Steel Framing Alliance reported that 81% of interior walls built in the United States used CFS framing With greater Introduction to recent trends in cold-formed steel