Structural Engineering Commons^™

Optimum Slot Weld Width For Cold-Formed Steel, Emilee A. Martin, Fredrick R. Rutz

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

Slot welds can be used for connections in cold-formed steel (CFS) structures. However, structural engineers will find AISI S100, “North American Specification for the Design of Cold-Formed Steel Structural Members” (AISI 2016) - which can be used for guidance in calculating structural capacity of many welds types - silent on this specific application.

Research at the University of Colorado Denver has been directed toward determination of the strength of slot welds in sheet steel. A comprehensive series of tests were performed to determine structural capacity and ductility of various slot weld widths using a metal inert gas (MIG) welding process. …

Wei-Wen Yu International Specialty Conference On Cold-Formed Steel Structures 2018: Recent Research And Developments In Cold-Formed Steel Design And Construction, 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.

Low Fatigue Response Of Crest-Fixed Cold-Formed Steel Drape Curved Roof Claddings, Krishanu Roy, James B. P. Lim, Amir Mohammad Yousefi, G. Charles Clifton, Mahen Mahendran

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

Cold-formed steel roof claddings are subjected to significant suction/uplift pressures during high wind events. In New Zealand, the strong prevailing winds makes this a common occurrence. Suction pressures are generated by the turbulence of the wind flow around the building which can vary both spatially and temporally. The weakest link in the roofing system is the connection between roof sheeting and screw fasteners, which if fails, can lead to progressive collapse of the whole roofing assembly. Fluctuating high wind suction pressures can result in either static or fatigue pull-through failure of the roof sheeting at its screw fastener connections. Current …

Stressed Skin Design Of Steel Sheeting Panels – Part 2: Shear Panels With Sheeting Fixed On All 4 Sides, A. M. Wrzesien, James B. P. Lim, I. A. Macleod, R. M. Lawson

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

In this paper, the strength and stiffness of different roof panels were investigated, in order to establish their ability to act as in-plane diaphragms for stressed skin design of cold-formed steel portal frames. A total of 6 roof panels, approximately 3 x 3m, were examined by testing with sheeting profiles fixed on 4 sides. A variety of sheeting profiles in two industry standard thicknesses of 0.5 and 0.7mm were tested, all using top-hat shaped purlins fixed with self-drilling, self-tapping screws. The experimental strength and stiffness of each panel were then compared against existing design methods. The Finite Element Analysis (FEA) …

Computational Modeling Of Joist-To-Ledger Connections In Cold-Formed Steel Diaphragms, Hernan Castaneda, M. Eng, Kara D. Peterson

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

Cold-formed steel framed buildings can involve a range of options for framing systems, including balloon framing, platform framing, and ledger framing. Transfer of lateral forces from the diaphragms to the wall system (and ultimately to the ground) depends on the interactions within the wall-diaphragm connection, which is dependent on choice of framing system. In ledger framing, floor joists are hung from top of wall studs via a rim track (ledger) and clip angle connection. Recent experimental efforts at Johns Hopkins University studied the wall-diaphragm connection with the goal of quantifying its contribution to overall diaphragm response. Results from these experiments …

Effect Of Connection Details On The Cyclic Behavior Of Nestable Screw Sidelaps, S. Torabian, H. Folk, Benjamin W. Schafer

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

The connection strength and stiffness sensitivity of screwed sidelaps in nestable steel decks to screw installation details has been experimentally explored via cyclic testing. The cyclic behavior of sidelaps has been recently incorporated in the high fidelity modeling and seismic evaluation of the steel deck diaphragm in rigid wall - flexible diaphragm buildings, where “unzipping” a sidelap (loss of a significant number of sidelap connections along a deck edge) could significantly reduce the seismic performance of the whole diaphragm. A total of 24 monotonic and cyclic sidelap tests have been performed in the Thin-Walled Structures Laboratory at Johns Hopkins University. …

Fire Resistance Of Cavity Insulated Light Gauge Steel Framed Walls, Anthony Deloge Ariyanayagam, Mahen Mahendran

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

Light-gauge steel framed (LSF) wall systems are made of cold-formed steel studs and tracks and lined with gypsum plasterboards. They are mostly cavity insulated to provide acoustic and thermal performance. Cavity insulation delays the temperature rise across the wall as it restrains the heat transfer. This delays the ambient plasterboard surface temperature rise and thus improves the insulation failure time of LSF walls. However, LSF walls are also used as load bearing walls. Having cavity insulation causes the fire side temperatures to increase rapidly, resulting in a higher temperature gradient across the stud depth. This leads to higher thermal bowing …

Shake Table Testing For Seismic Response Evaluation Of Cold-Formed Steel-Framed Nonstructural Architectural Components, Luigi Fiorino, Bianca Bucciero, Tatiana Pali, Ornella Iuorio, Raffaele Landolfo

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

The seismic response evaluation of cold-formed steel-framed nonstructural architectural components was investigated in an experimental campaign carried out within of the research study agreement between Knauf Gips KG and the Department of Structures for Engineering and Architecture of the University of Naples “Federico II”. The main objective of this research was to investigate the seismic performance of drywall nonstructural systems, i.e. cold-formed steel-framed indoor partition walls, outdoor façade walls and suspended ceilings. The present paper deals with the dynamic shake table tests. The tests were carried out on two different typologies of prototypes (Type 1 and Type 2) for a …

Numerical Simulation Of The Thermal And Mechanical Behavior Of Cold-Formed Steel Composite Floor Under Fire Conditions, Jixian Peng, Wei Chen, Jihong Ye, Zhengliu Wang

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

Cold-formed steel (CFS) building structures are generally acknowledged as green and industrialized buildings, and the fire resistance behavior has become an important issue. Previous studies were mainly to investigate the fire performance of load-bearing CFS walls lined with different panels. Based on the finite element (FE) software package, ABAQUS, this paper presented a numerical simulation on a new CFS channel joist – ALC (autoclaved lightweight concrete) composite floor under fire conditions. Finally, the present numerical simulation of CFS composite floor in fire was compared with previous full-scaled fire experiments of such floors. The results showed that the temperature progression of …

New Web Crippling Design Rules For Cold-Formed Steel Beams, L. Sundararajah, M. Mahendran, P. Keerthan

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

Lipped channel beams (LCBs) and SupaCee sections are commonly used as floor joists and bearers in the construction industry. SupaCee section is one of the cold-formed steel members, which is increasingly used in the building construction sector. It is characterized by unique ribbed web and curved lip elements, and is claimed to be more economical with extra strength than the traditional channel sections. These thin-walled LCBs and SupaCee sections are subjected to specific local and global failures, one of them being web crippling. Several experimental and numerical studies have been conducted in the past to study the web crippling behaviour …

New Proposals For The Direct Strength Method Of Design Of Cold-Formed Steel Beams With Holes In Shear, Song Hong Pham, Cao Hung Pham, Colin A. Rogers, Gregory J. Hancock

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

In the latest North American Specification for the design of cold-formed steel structural members AISI S100-16, an empirical approach is specified to design beams with web holes in shear. Recently, a Direct Strength Method (DSM) of design for shear for perforated beams with the aspect ratio (shear span / web depth) of 1.0 has been proposed. This paper presents a comprehensive review of the proposal and an experimental validation using a test series on beams with the aspect ratio of 2.0 and with various square and circular web opening sizes conducted at the University of Sydney, and other experimental data …

Experimental Investigation Into The Behavior Of Back-To-Back Gapped Built-Up Cold-Formed Steel Channel Sections Under Compression, Krishanu Roy, Tina Chui Huon Ting, Hieng Ho Lau, James B. P. Lim

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

Back-to-back gapped built-up cold-formed steel channel-sections are used as compression members in cold-formed steel structures, such as trusses, space frames and portal frames etc. Because of the complex and non-uniform cross section of the back-to-back gapped built- up cold-formed steel channel columns, it is difficult to calculate the strength of these sections accurately. Current guidance by the direct strength method in the AISI Specification and the Australian/New Zealand Standard doesn’t include the gap between the back-to-back channels, thus not being able to predict the axial capacities of these sections accurately. In the literature, very few results have been reported for …

Cyclic Performance And Behavior Characterization Of Steel Deck Sidelap And Framing Connections, S. Torabian, D. Fratamico

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

A wide variety of steel deck sidelaps and framing connections have been experimentally studied to characterize the cyclic performance required in seismic evaluation of steel deck diaphragms. This study intends to provide cyclic test results of common steel deck connections including screw nestable and top arc seam sidelaps; and powder actuated fasteners, arc spot weld, and arc seam weld framing connections. A total of 24 sidelap and 36 framing connection tests have been performed in the Thin-Walled Structures Laboratory at Johns Hopkins University by NBM Technologies. The connection test results have been used to parameterize a nonlinear hysteretic spring element …

Screw And Pin Fastener Tests For Cold-Formed Steel, Brian S. Wilson, Fredrick R. Rutz, James R. Harris

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

Because of limited available information on strength and ease of installation of specific fasteners for a particular application to a steel deck diaphragm, a preliminary testing program comparing the shear strength of commercially available screws and gas-actuated shot pins was conducted by J. R. Harris and Company at the University of Colorado Denver in 2018. A test was designed to explore the behavior and capacity of various fasteners, securing two and three pieces of sheet steel of various thicknesses together. Specimens were fabricated and load tested, with the sheet steel pieces in tension, so the fasteners were subject to shear. …

Sdi Steel Deck On Cold-Formed Steel Framing Design Manual, Thomas Sputo

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

No abstract provided.

Transverse Shear Stiffness Of Bolted Cold-Formed Steel Storage Rack Upright Frames With Channel Bracing Members, Nima Talebian, Benoit P. Gilbert, Hassan Karampour

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

Accurately evaluating the transverse shear stiffness of cold-formed steel storage rack upright frames is crucial to calculate the frame elastic buckling load, perform earthquake design and serviceability checks. This is especially essential for high-bay racks, which are subjected to large second-order effects, and racks supporting the building enclosure, which are exposed to transverse wind loads. The shear behaviour of these frames is poorly understood and experimental testing is usually required to measure their stiffness. Previous studies have shown that Finite Element Analyses (FEA), solely using beam elements, fail to reproduce experimental test results and may overestimate the transverse shear stiffness …

Investigation On Shear Capacity For Screw Connections Of Cold-Formed Steel Framed Shear Walls With Steel Sheathing, Ruoqiang Feng, Ying Ma

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

Experimental and numerical investigations were carried out to learn the shear capacities for screw connections of cold-formed steel framed shear walls with steel sheets for the base layer combined with gypsum wallboards for the face layer. The design methods of test specimens, the loading equipment and the data processing method were introduced. According the phenomenon of tests for multiple self-drilled screw connections, the loading-deformation curves, shear capacity and failure modes were testified. The influence of end distance of screw, edge distance of screw, diameter of screw, spacing of screw, thickness of steel sheets, thickness of gypsum wallboards, thickness of studs …

Planning The Future Of North American Cold-Formed Steel Design Standards, Benjamin W. Schafer, Jay Larson, Helen Chen

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

Growth in cold-formed steel structures has long been tied to developing and advancing the engineering standards that govern their use in construction. The American Iron and Steel Institute (AISI) has taken a leadership role in this activity in North America since 1946. Conventional standards providing closed-formed solutions to member capacity, such as the recently completed suite of AISI Standards in 2015 and 2016. These standards have reached an impressive level of maturity given the complexity of designing entire (building) structural systems out of steel that is rarely greater than 2mm thick. However, the demands on the structural engineer designing cold-formed …

Experimental Study Of Apex Connection Stiffness And Strength Of Cold-Formed Steel Double Channel Portal Frames, J. Peng, J. Bendit, H. B. Blum

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

Cold-formed steel portal frames are an increasingly popular structure in the housing and industrial sectors, and are commonly used for garages, sheds, and shelters. Longer span cold-formed steel portal frames are relatively new to the market, and as a result limited design guidance and recommendations exist, including the strength and stiffness of the connections. The apex connection stiffness affects the distribution of internal actions and deflections of a portal frame, and therefore, it is necessary to quantify the apex stiffness for use in design models to accurately determine the frame behavior. An experimental program was carried out on a series …

Finite Element Modeling And Validation Of Steel Sheathed Cold-Formed Steel Framed Shear Walls, Amanpreet Singh, Tara C. Hutchinson

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

The objective of this paper is to validate the concept of utilizing a truss-element based finite element model for capturing the in-plane cyclic response of steel sheathed cold-formed steel (CFS) framed shear wall. The model is developed within the OpenSees finite element platform. Steel sheathed CFS shear walls show shear buckling of their sheathing as a tension field develops. This inelastic behavior of the shear walls is replicated by using the Pinching4 material for truss elements acting along the tension field. Importantly, the model employs beam-column elements for framing members, rotational springs for representing frame stiffness and vertical springs for …