Structural Engineering Commons^™

Acoustic Performance Of Different Cold-Formed Studs In Double-Leaf Walls By Finite Element Analysis And Experiment, V. B. Nguyen, T. Morgan, M. A. English, M. A. Castellucci

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

Cold-formed steel studs are often used in lightweight partition walls to provide structural stability but in the same time they change the acoustic performance of the whole system. The overall design of such lightweight structures for acoustic sound insulation becomes very complicated as the sound passing through stud needs to be quantified. One of the greatest challenges is to characterise the stud’s geometric effects on the sound transmission of the partition walls. This paper presents a Finite Element modelling approach and results into the acoustic performance of cold-formed studs in double-leaf walls which are placed in between a source room …

Fire Resistance Prediction Of Load Bearing Cold-Formed Steel Walls Lined With Gypsum Composite Panels, Wei Chen, Jihong Ye

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

An innovative load-bearing cold-formed steel (CFS) wall lined with gypsum composite panels was developed with the goal of improving the construction efficiency and fire performance of these walls for applications in mid/high-rise buildings. The gypsum composite panel was formed by sandwiching insulation and plasterboard strips between two layers of gypsum plasterboards. Subsequently, the predicted fire resistance of these CFS walls was predicted based on our previously developed and experimentally validated modeling method. The degenerated material properties of the cold-formed steel and thermal physical property of the gypsum plasterboard and aluminum silicate wool were obtained from our pervious experimental investigations and …

Improvements To The Prediction Of Brace Forces In Z-Purlin Roof Systems With Support + Third Point Bracing, Michael W. Seek

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

The Component Stiffness Method is a displacement compatibility method used to analyze C- and Z- section supported roof systems. The method provides a detailed analysis of the flexibility in the roof system and the distribution of forces as they flow out of the system. Parametric studies of the equations for typical roof systems have shown that by ignoring the flexibility of some of the components, the method can be simplified with little impact on the anchorage forces calculated. Changes have also been made to the way in which cross section deformations are incorporated into the method. This paper focuses on …

Influence Of Diagonal Bracing Restraint On Cold-Formed Steel Perforated Columns Under Axial Compression, Chong Ren, Xianzhong Zhao

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

This paper presents a numerical investigation on the influence of diagonal bracing restraint on cold-formed steel perforated columns subjected to axial compression. Finite element method (FEM) is employed to analyse the structural behaviour of perforated columns. The results obtained from the present study highlight the influence of diagonal bracing restraint on post-buckling of columns, and the distortional-flexural mode interaction is also discussed. Furthermore, the accuracy of the present model is validated by comparing the results against the available experimental data.

Pull-Through Failure Tests Of Thin Steel Roof Battens Under Wind Uplift Loads, Mayooran Sivapathasundara, Mahen Mahendran

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

Thin profiled steel roof sheeting and battens are increasingly used in the construction of roofing systems of residential, commercial, industrial and farm buildings in Australia. The critical load combination of external wind suction and internal wind pressures that occur during high wind events such as thunderstorms and tropical cyclones often dislocate the roofing systems partially or even completely due to premature roof connection failures. Past wind damage investigations have shown that roof sheeting failures occurred at their screw connections to battens. In most of these cases, the screw fastener head pulled through the thin roof sheeting whilst the screw fasteners …

Towards Load-Deformation Models For Screw-Fastened Cold-Formed Steel-To-Steel Shear Connections, C. D. Moen, D. A. Padilla-Llano, S. Corner, C. Ding

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

This paper summarizes results from an experimental program considering single-fastened cold-formed steel-to-steel shear connections. Fastener motion (displacement and tilting angle) and bearing deformation occurring on the connecting members at the fastener location were captured using an automated, optical non-contact measurement procedure. The results are used to relate cold-formed steel-to-steel shear connection load-deformation response to tilting and bearing response. A general steel-to-steel single shear fastener load-deformation equation is also proposed and demonstrated.

Numerical Simulation On Dynamic Behavior Of A Cold-Formed Steel Framing Building Test Model, Yuanqi Li, Rongkui Ma, Zuyan Shen

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

A nonlinear dynamic numerical simulation on seismic behavior of a two-story cold-formed steel framing building full-scale shaking table test model was carried out by the way of from components to integral structure. Firstly, refined numerical model of shear wall was established, and restoring force models of screw connections between the framing and sheathings were integrated into the numerical model of shear wall. The refined numerical model of shear wall was verified by tests. Secondly, based on refined numerical model of shear wall and modified exponential “Foschi” skeleton curve, uniform restoring force skeleton curves of two typical shear walls of the …

Fastener-Based Computational Models With Application To Cold-Formed Steel Shear Walls, G. Bian, S. G. Buonopane, Hung Huy Ngo, Benjamin W. Schafer

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

The objective of this paper is to validate a tool that design engineers could employ to develop mechanics-based predictions of the lateral response of wood-sheathed cold-formed steel (CFS) framed shear walls applicable in a wide variety of situations. Wood framed shear walls enjoy a variety of tools, most notably SAPWood and its predecessor CASHEW, that provide a means to predict the complete hysteretic behavior of a shear wall based on the nail fastener schedule and board selection. The existence of these tools helps engineers in unique design situations, encourages innovation in shear wall design particularly for Type I shear walls, …

In-Plane Behavior Of Cold-Formed Steel-Framed Shear Wall Panels Sheathed With Fibre Cement Board, Rojit Shahi, Nelson Lam, Emad Gad, Ismail Saifullah, John Wilson, Ken Watson

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

Shear wall panels are commonly used as lateral load resisting elements to provide stability of the cold-formed steel-framed houses in Australia against wind and earthquake actions. The effectiveness of their lateral resistance behavior is obtained usually by experimental testing although it can also be done by analytical modeling. This paper presents racking test results of steelframed wall panels with different aspect ratios sheathed with fibre cement board subjected to monotonic and cyclic loading protocol. Performance parameters of the wall panels are obtained from the experimentally observed load-deflection curves using various existing methods and evaluation method is proposed. The evaluation method …

Experimental Seismic Behavior Of The Cfs-Nees Building: System-Level Performance Of A Full-Scale Two-Story Light Steel Framed Building, Kara D. Peterman, Rob L. Madsen, Benjamin W. Schafer

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

In the summer of 2013, testing of two full-scale cold-formed steel (CFS) framed buildings under seismic excitations took place at the Structural Engineering and Earthquake Simulation Lab (SEESL) at the University at Buffalo. Utilizing the twin shake tables, the two-story building specimens were subjected to ground motions from the 1994 Northridge earthquake. These experiments were conducted as a part of the CFS-NEES experimental effort in an attempt to advance cold-formed steel earthquake engineering and design. Two buildings were tested: the first, a specimen constructed with only structural components (CFS-framed gravity walls, shear walls, floor and roof diaphragms, with OSB sheathing …

Local Buckling Hysteretic Nonlinear Models For Cold-Formed Steel Axial Members, D. A. Padilla-Llano, C. D. Moen, M. R. Eatherton

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

This paper studies the energy dissipation and damage in thin walled members that experience local buckling and presents an approach to model cold-formed steel (CFS) axial members that experience local buckling deformations. The model is implemented in OpenSees using hysteretic models for CFS axial members calibrated using experimental responses. Results from thin-shell element simulations using ABAQUS show that energy dissipation in thin plates dissipates through inelastic strains and yielding that concentrates in damaged zones that extent approximately the length of a buckled half-wave (L_cr). Generally damage accumulates in one zone but when more than one damaged zone occurred …

Constrained Finite Element Method: Demonstrative Examples On The Global Modes Of Thin-Walled Members, S. Ádány

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

In this paper a novel method is presented for the modal decomposition of thin-walled members. The proposed method follows the logic of the constrained finite strip method (cFSM), however, polynomial longitudinal shape functions are applied together with a longitudinal discretization. Thus, strips are transformed into multiple shell finite elements. The longitudinal shape functions are selected in such a way that modal decomposition similar to cFSM can be realized, therefore, the new method can conveniently be described as constrained finite element method (cFEM), possessing all the modal features of cFSM, but with significantly more flexible applicability. The method is briefly presented …

The 2013 Aisi Cold-Formed Steel Design Manual, Joshua Buckholt, Richard C. Kaehler, Helen Chen

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

The 2013 edition of the AISI Cold-Formed Steel Design Manual has been published. The new edition includes updated and newly developed example problems and design aids covering new material in the 2012 edition of the AISI North American Specification for the Design of Cold-Formed Steel Structural Members (NA Specification). Also published with the Manual are the NA Specification and the Commentary.

Steel Deck Institute Design Manuals For Floor And Roof Deck, Thomas Sputo

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

The Steel Deck Institute (SDI) has developed new design manuals to assist in the use of their consensus floor and roof deck standards. The SDI Floor Deck Design Manual, 1st Edition (FDDM) is based on the requirements of the ANSI/SDI NC-2010 Standard for Non-composite Steel Floor Deck and the ANSI/SDI C-2011 Standard for Composite Steel Floor Deck-Slabs. The SDI Roof Deck Design Manual, 1st Edition (RDDM) is based on the requirements of the ANSI/SDI RD-2010 Standard for Steel Roof Deck. Both manuals contain information on available deck profiles and finishes, and design and installation information. Additionally, both manuals …

Cold-Formed Steel Channel Sections With Web Stiffeners Subjected To Local And Distortional Buckling — Part Ii: Parametric Study And Design Rule, Liping Wang, Ben Young

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

A parametric study of cold-formed steel channel sections with web stiffeners subjected to bending was performed using finite element analysis (FEA). An accurate finite element model was used for the parametric study. The parametric study included 75 beams of plain and lipped channel sections with web stiffeners. The beams were simply supported and subjected to four-point bending. The strengths and failure modes of specimens obtained from experimental and FEA results were compared with design strengths predicted using the direct strength method (DSM) specified in the North American Specification for cold-formed steel structures. The comparison shows that the design strengths predicted …

Aisi Newly Developed Standard Aisi S310-13, North American Standard For The Design Of Profiled Steel Diaphragm Panels, John Mattingly, Helen Chen

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

AISI S310, North American Standard for the Design of Profiled Steel Diaphragm Panels, has been approved by AISI consensus committee and approved by American National Standard Institute (ANSI) as American National Standard (ANS). This standard determines the resistance and stiffness of steel panels with or without concrete-fills, and the resistance and stiffness of connections in a diaphragm. Both analytical and test methods are provided in the standard. In this paper, a brief review of the background information and design provisions is provided.

Finite Element Analysis Of Cold-Formed Dimpled Steel Columns, V. B. Nguyen, M. A. English, M. A. Castellucci

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

Dimpled steel products are produced from the combination of an innovative dimpling process and a traditional forming process such as cold-roll forming or press-braking. The wider use of cold-formed dimpled steel members has promoted considerable interest in the local instability and strength of these members. Of particular interest is their buckling behaviour and ultimate strength capacity. However, the dimpling process produces cold-formed sections with a complex ‘dimpled’ surface topography and the ‘dimpled’ material is nonuniformly work hardened through the entire thickness. Owing to these complex issues, there are no existing methods to calculate the buckling strength of the dimpled products …

Gbtul 2.0 −A New/Improved Version Of The Gbt-Based Code For The Buckling Analysis Of Cold-Formed Steel Members, Rui Bebiano, Dinar Camotim, Rodrigo Gonçalves

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

This paper presents the very recent 2.0 release of software GBTUL – a computer code developed by the authors and made available as freeware at the website of the Department of Civil Engineering of the Technical University of Lisbon (Bebiano et al. 2013). The program performs linear buckling and vibration analyses of thin-walled bars based on Generalized Beam Theory (GBT), a bar theory that accounts for cross-section deformation. Its domain of application is much wider than that of the previous release (1.0ß): indeed, it is now possible to analyze single or multi-span members (i) with various support conditions, including those …

Laser Scanning To Develop Three-Dimensional Fields For The Precise Geometry Of Cold-Formed Steel Members, Xi Zhao, Benjamin W. Schafer

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

Geometric imperfections play an important role in the performance and behavior of cold-formed steel members. The objective of this paper is to detail a newly developed imperfection measurement rig, where the full three-dimensional (3D) imperfect geometry of a cold-formed steel member can be measured and reconstructed. The measurement results in a dense three-dimensional point cloud that may be utilized to provide precise knowledge of the basic member dimensions (width, angle, radius including variation along the length), frequency content in the member (waviness, local dents, etc.), or directly as the exact geometry of the member. Practical applications of the data include …

Tailoring Compression Performance Of Cold-Formed Steel Columns, Talha Ekmekyapar, M. Tolga Göğüş, Mustafa Özakça

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

Since thin-walled structural analysis and design procedures are utilized for cold-formed steel columns, it is first necessary to understand thin plate behavior to employ proper cross sections which will serve under compression actions. As is well known, thin plates without any longitudinally and/or laterally stiffening elements usually are not present in structural applications. These stiffening elements significantly improve local buckling and collapse characteristics of plates, providing optimized solutions in terms of strength and cost. In cold-formed steel industry there exist some tailoring methods for columns to use the cross-section material more effectively. Designing lipped channels instead of plain ones or …

Numerical Studies Of Rivet-Fastened Rectangular Hollow Flange Channel Beams, R. Siahaan, P. Keerthan, M. Mahendran

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

The rivet-fastened rectangular hollow flange channel beam (RHFCB) is a new cold-formed hollow section proposed as an alternative to welded hollow flange beams. It is a monosymmetric channel section made by rivet-fastening two torsionally rigid rectangular hollow flanges to a web plate. This method will allow the designers to develop optimum sections, with affordable rivet connection between their web and flange elements. In addition to this unique geometry, the rivet-fastened RHFCBs also have unique characteristics relating to their stress-strain characteristics, residual stresses, initial geometric imperfections and hollow flanges that are not encountered in conventional hot-rolled and cold-formed steel channel sections. …

Section Moment Capacity Tests Of Rivet-Fastened Rectangular Hollow Flange Channel Beams, R. Siahaan, P. Keerthan, M. Mahendran

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

The rivet-fastened rectangular hollow flange channel beam (RHFCB) is a new cold-formed hollow section proposed as an alternative to welded hollow flange steel beams. It is a mono-symmetric channel section made by rivet fastening two torsionally rigid rectangular hollow flanges to a web plate. This method will allow the designers to develop optimum sections, with affordable rivet connection between the web and flange elements. The new rivet-fastened RHFCB has unique characteristics that are not encountered in conventional hot-rolled and cold-formed steel channel sections. Therefore an experimental study consisting of 15 section moment capacity tests was conducted with different rivet spacings …

Developments In The Finite Strip Buckling Analysis Of Plates And Channel Sections Under Localised Loading, Gregory J. Hancock, Cao Hung Pham

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

Thin-walled sections under localised loading may lead to web crippling of the sections. This paper develops the Semi-Analytical Finite Strip Method (SAFSM) for thin-walled sections subject to localised loading to investigate web crippling phenomena. The method is benchmarked against analytical solutions, Finite Element Method (FEM) solutions, as well as Spline Finite Strip Method (SFSM) solutions.

The Behaviour Of Cold-Formed C-Sections With Square Holes In Shear, Cao Hung Pham, Yu Han Chin, Peter Boutros, Gregory J. Hancock

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

Cold-formed structural C-section members may be subjected to axial force, bending and shear or combinations of either two or all of these actions. Design methods for these sections are normally specified in the Australian/New Zealand Standard for Cold-Formed Steel Structures (AS/NZS 4600:2005) or the North American Specification for Cold-Formed Steel Structural Members (2012). Both Effective Width Methods (EWM) and the newly developed Direct Strength Method (DSM) can be used for the design. For shear, the NAS S100 2012 Edition has recently included DSM design rules just for the plain sections only. To date, no rules are presented in this specification …

Experimental Study Of Longitudinally Stiffened Web Channels Subjected Predominantly To Shear, Luciano A. Bruneau, Cao Hung Pham, Gregory J. Hancock

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

The Direct Strength Method (DSM) of design of cold-formed sections has recently been extended in the North American Specification for Cold-Formed Steel Structural Members-NAS S100:2012 to include shear. The two new features of the DSM rules for shear researched are the effect of full-section shear buckling as opposed to web-only shear buckling and Tension Field Action (TFA). The prequalified sections in the rules include sections with flat webs and webs with small intermediate longitudinal stiffeners. In order to extend the range to larger intermediate stiffeners as occurs in practice, a series of fourteen shear tests have been performed at the …

Numerical Studies Of Collapse Behaviour Of Multi-Span Beams With Cold Formed Sigma Sections, F. L. Wang, J. Yang, J. Lim

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

Multi-span cold-formed steel beams are widely used for roof purlin and cladding rails due to their high strength to weight ratio and ease of installation on site. There are a wide variety of cross-sectional shapes e.g. C, Z, top hat and sigma sections. A sigma section possesses several advantages such as high cross-sectional resistances and large torsional rigidities compared with standard Z or C sections.

Traditional design methods for cold-formed multi-span steel beams have been based on elastic theory, such as the Effective Width Method (EWM) and the Direct Strength Method (DSM). Both methods ignore the effect of redistribution of …

Experimental Investigation On Ultimate Capacity Of Eccentrically-Compressed Cold-Formed Beam-Columns With Lipped Channel Sections, Yuanqi Li, Yinglei Li, Yanyong Song

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

This paper is mainly concerned with the in-plane behavior of eccentrically-compressed cold-formed steel beam-columns with lipped channel sections. The tested members are classified into three series by loading types including: axial compression and major axis bending (X), axial compression and minor axis bending (lips in tension, Y1), and axial compression and minor axis bending (lips in compression, Y2). A numerical model is developed and verified by the experimental results. Then the elastic local buckling loads are discussed based on test results, numerical analysis, and design methods. The comparison between test strength and nominal strength obtained by AISI specification indicates that …

Shape Optimisation Of Cold-Formed Steel Profiles With Manufacturing Constraints - Part I: Algorithm, Bin Wang, Benoit P. Gilbert, Adrien M. Molinier, Hong Guan, Lip H. Teh

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

This paper presents a Genetic Algorithm optimisation method with manufacturing constraints for shape optimisation of cold-formed steel (CFS) profiles. Previous studies on unconstrained shape optimization of CFS crosssections, where the sole aim was to optimise the weight-to-capacity ratio of the profiles, yielded cross-sections that cannot be manufactured. Current coldforming processes, such as roll-forming and brake-pressing, have limited ability to form continuously curved surfaces without discrete bends. This paper defines simple manufacturing rules and introduces them into the evolutionary algorithm. Augmented Lagrangian constraint-handling technique, with equality and inequality constrained violations, is used to avoid ill-conditioned problems. The ability and accuracy of …

Shape Optimisation Of Cold-Formed Steel Profiles With Manufacturing Constraints - Part Ii: Applications, Bin Wang, Benoit P. Gilbert, Adrien M. Molinier, Hong Guan, Lip H. Teh

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

This paper uses the Genetic Algorithm (GA)-based optimisation method for cold-formed steel (CFS) profiles with manufacturing constraints, developed in the companion paper, to shape-optimise simply-supported and singly-symmetric open-section columns. Having a uniform wall thickness of 0.047 inch (1.2 mm), the columns are subjected to a compressive axial load of 16,860 lbf (75kN) and optimised for yielding and global buckling. Column lengths ranging from 3.28 ft (1,000 mm) to 9.84 ft (3,000 mm) are investigated. The algorithm is run with and without considering the manufacturing constraints. Differences between the two types of cross-sections, i.e. manufacturable and non-manufacturable, are evaluated. The influence …

Understanding The Global Buckling Behavior Of Thin-Walled Members With Slotted Web, B. Geleji, M. Szedlák, D. Visy, S. Ádány

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

In this paper flexural buckling of thin-walled members with holes are discussed. Members with few but large openings, as well as with slotted webs are studied. Large number of finite element analyses has been performed, by using a carefully constrained shell finite element model in order to exclude the distortion of the cross-section, which makes it possible to analyze flexural buckling separately from other modes. Based on the results general conclusions are drawn regarding the global behavior of members with holes. Moreover, analytical models are developed for column members with slotted webs, with neglecting or with considering the effect of …