Engineering Commons^™

Strain And Stress Distributions In Composite Deck Slabs: A Numerical Study, Vitaliy V. Degtyarev

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

This paper describes results of a study on strain and stress distributions in compact and slender composite deck slabs using nonlinear three-dimensional finite element models. The slabs were modeled as flexural members made of steel deck units and structural concrete fillings interconnected at the interface with nonlinear springs representing bond between two materials. The models are capable of accounting for partial interaction between the deck and the concrete, discrete concrete cracking in the slab tension zone, and nonlinear behavior of the materials and the interface. They were validated against published test data and have proved to be effective in predicting …

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 …

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.

Investigation On Seismic Performance Of Cold-Formed Steel Portal Frames, Yuanqi Li, Zhijian Xu, Yinglei Li, Yunfei Peng

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

A series of monotonous loading and hysteresis loading tests on cold-formed steel portal frames were conducted in this paper. The averaged ductility factor value of tested frames is 3.15 and the strength and stiffness degradation are not obvious during the test. The failure mode of frame is local buckling at column bases followed by local buckling at the top of columns, which lead to the dropping of frame’s load-carrying capacity. Then, the finite element model is developed and the analysis results match well with the test results. The research in this paper indicates that cold-formed steel portal frame has a …

Effect Of Stressed-Skin Action On The Behaviour Of Cold-Formed Steel Portal Frames, A. M. Wrzesien, James B. P. Lim, R. M. Lawson

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

This paper describes six full-scale laboratory tests conducted on cold-formed steel portal frames buildings in order to investigate the effects of joint flexibility and stressed-skin diaphragm action. The frames used for the laboratory tests were of span of 6 m, height of 3 m and pitch of 10⁰; the frame spacing was 3 m. The laboratory test setup represented buildings of length of 9 m, having two gable frames and two internal frames. Tests were conducted on frames having two joint sizes, both with and without roof cladding. It was shown that as a result of stressed-skin diaphragm action, under …

Effect Of Stressed-Skin Action On Optimal Design Of A Cold-Formed Steel Portal Framing System, Duoc T. Phan, Andrzej M. Wrzesien, James B. P. Lim, Iman Hajirasouliha

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

Cold-formed steel portal frames can be a viable alternative to conventional hot-rolled steel portal frames. They are commonly used for low-rise commercial, light industrial and agricultural buildings. In this paper, the effect of semi-rigid joints and stressed-skin action are taken into account in the optimal design of cold-formed steel portal frames. A frame idealization is presented, the results of which are verified against full-scale. A real-coded niching genetic algorithm (RC-NGA) is then applied to search for the minimum cost for a building of span of 6 m, height-to-eaves of 3 m and length of 9 m, with a frame spacing …

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 …

Structural Strength Of Lapped Cold-Formed Steel Z-Shaped Purlin Connections With Vertical Slotted Holes, J. Liu, L. Xu, S. Fox

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

Lapped joints of cold-formed steel (CFS) Z-shaped purlins are extensively used in metal building roof systems. The research that has been carried out so far for these lapped connections is primarily focused on connections with round holes. However, the lapped connections with vertical slotted holes are extensively used in current construction practice to simplify the erection of continuous Z-shaped roof purlins. There are no design guidelines or recommendations available for CFS Z-purlin lapped connections with vertical slotted holes.

Presented in this paper are the results of an experimental study on the structural strength behaviour of lapped CFS Z-shaped purlin connections …

Direct Strength Method For Ultimate Strength Of Bolted Moment-Connections Between Cold-Formed Steel Channel Members, James B. P. Lim, Gregory J. Hancock, G. Charles Clifton, Cao Hung Pham

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

Experimental tests have previously shown that the strength of bolted moment-connections between cold-formed steel members, where the connections are formed through an array of bolts in the web, is dependent on the length of the bolt-group. This reduced strength has been observed in tests on portal frame joints as well as over-lapped purlin joints. For a short bolt-group length, in the order of the depth of the section, this paper shows that a reasonable lower bound to this reduced strength can be predicted by using the Direct Strength Method (DSM), modified to include the effect of the bimoment at the …

Development Of A Novel Pinned Connection For Cold-Formed Steel Trusses, Chris D. Mathieson, G. Charles Clifton, James B. P. Lim

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

Cold-formed steel trusses are a popular form of construction for light-weight buildings, particularly portal frame structures, for which spans up to 25m are increasingly common. In these long span trusses, providing high strength connections with sufficient elastic stiffness is a current limitation to developing cost-effective solutions. A novel pin-jointed truss connection named the Howick Rivet Connector (HRC) has been tested, firstly in a T-joint arrangement, then in a truss assemblage to determine its reliable strength and stiffness. Results showed that the HRC performs similarly to a bolted connection in terms of failure modes observed and loads reached. Additionally, the process …

Lateral Loading Response Of Cfs Framed Shear Wall With Cement Board Panels, N. Baldassino, M. Accorti, R. Zandonini, F. Scavazza, C. A. Rogers

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 steel-framed 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 …

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 …

Evaluation Of The Seismic Performance Of Light Gauge Steel Walls Braced With Flat Straps, Iuorio Ornella, Macillo Vincenzo, Terracciano Maria Teresa, Pali Tatiana, Fiorino Luigi, Landolfo Raffaele

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

The development of light weight steel structures in seismic area as Italy requires the upgrading of National Codes. To this end, in the last years a theoretical and experimental study was carried out at the University of Naples within the research project RELUIS-DPC 2010-2013. The study focused on "all steel design" solutions and investigated the seismic behaviour of strap braced stud shear walls. Three wall configurations were defined according to both elastic and dissipative design criteria for three different seismic scenarios. The lateral in-plane behavior of these systems were evaluated by 12 tests performed on full-scale CFS strap-braced stud wall …

Fragility Curves For Thin-Walled Cold-Formed Steel Wall Frames Affected By Ground Settlements Due To Land Subsidence, Luis A. Hernández-Castillo, Jose A. Ortiz-Lozano, Martin Hernández-Marín, Jesús Pacheco-Martínez, Mario E. Zermeño-Deleón, Juan J. Soto-Bernal, Jorge Ramos-Ruizflores, Miguel A. Soto-Zamora

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

Land subsidence phenomenon due to ground water withdrawal is a current problem in many places around the world, particularly in the shallows of Mexico. This causes ground differential settlements that affect structures, mainly dwellings and buildings based on reinforced concrete and masonry. Eventually, these structural materials do not exhibit an adequate performance beyond a certain level of angular distortion. This work presents the results about a study regarding the performance of thin-walled cold-formed steel wall frames with different sheathing systems affected by angular distortions simulating ground differential settlements due to land subsidence. The wall frames are composed by vertical (studs) …

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 …

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 …

Towards Quantifying Beneficial System Effects In Cold-Formed Steel Wood-Sheathed Floor Diaphragms, A. Chatterjee, Y. Xiang, C. D. Moen, S. R. Arwade, Benjamin W. Schafer

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

Cold-formed steel wood-sheathed floor diaphragm system behavior is analyzed from a system reliability perspective. Floor systems consisting of oriented strand board (OSB), cold-formed steel (CFS) joists, tracks and screw fasteners are modeled using shell and spring elements in ABAQUS. (Dassault-Systems ())The models consider typical seismic demand loads, with careful treatment of light steel framing diaphragm boundary conditions and OSB sheathing kinematics, i.e., two sheets pulling apart or bearing against each other at an ultimate limit state, consistent with existing experimental results. The finite element results are used to build surrogate mathematical idealizations (series, parallel-brittle and parallel-ductile) for the critical system …

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.

Cold-Formed Lean Duplex Stainless Steel Rectangular Hollow Sections In Combined Compression And Bending, Yuner Huang, Ben Young

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

An experimental investigation of cold-formed lean duplex stainless steel members in combined compression and minor axis bending is performed. The test specimens were cold-rolled from flat strips of lean duplex stainless steel grade EN 1.4162 into two rectangular hollow sections. Different eccentricities were applied to the rectangular hollow sections, so that a beam-column interaction curve for each series of test can be obtained. Initial overall geometric imperfections of the members were measured prior to testing. The ultimate loads and the failure modes of each specimen were obtained. Failure modes include flexural buckling as well as interaction of local and flexural …

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.

22nd International Specialty Conference: Recent Research And Developments In Cold-Formed Steel Structures, Wei-Wen Yu Center For Cold-Formed Steel Structures

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

No abstract provided.

The Effects Of End Conditions On The Load Capacity Of Cold-Formed Steel Column Members Of Lipped Channel Cross-Section With Perforations Subjected To Compression Loading, Martin Macdonald, Muditha P. Kulatunga

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

The effects of end boundary conditions on the compressive load carrying capacity of cold-formed lipped channel sections with perforations are investigated and discussed. Most structural cold-formed steel members are typically manufactured with perforations. These perforations are pre-cut to accommodate electrical, plumbing, and heating services and so on. Due to the size, shape, and position of perforations and end conditions, ultimate strength and elastic stiffness of a structural member can be varied. This paper describes the ultimate strength results obtained from numerical, experimental, and theoretical investigations for two types of end conditions namely, flat-end and fixed-fixed. The numerical results given have …

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 …

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 …