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2018

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Articles 1021 - 1050 of 8951

Full-Text Articles in Engineering

Localised Screw Connection Failures In Cold-Formed Steel Roofing Systems, Mayooran Sivapathasundaram, Mahen Mahendran Nov 2018

Localised Screw Connection Failures In Cold-Formed Steel Roofing Systems, Mayooran Sivapathasundaram, Mahen Mahendran

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

Lightweight roofing systems made of thin and high strength steel roof sheeting and battens are commonly used in low-rise buildings. However, they often fail frequently at their screw fastener connections during wind storms due to inadequate connection capacities. Two localised failures, known as pull-through and pull-out failures at the screw fastener connections, have been the root cause for extensive loss of roofing systems under high wind uplift loads. Such premature connection failures often cause partial or even complete loss of steel roofing systems and severe damage to building contents. Therefore many experimental studies have been conducted to investigate the pull-through …


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 Nov 2018

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 1: Shear Resistance And Flexibility Of Screw Lapped Joists, A. M. Wrzesien, James B. P. Lim, I. A. Macleod, R. M. Lawson Nov 2018

Stressed Skin Design Of Steel Sheeting Panels – Part 1: Shear Resistance And Flexibility Of Screw Lapped Joists, 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)

The shear resistance and flexibility of a steel roof diaphragm depend largely on shear resistance and slip flexibility of the single screw lap joint. In this paper, screw connections relevant to modern roof construction are investigated. The tests provided experimental values of shear/tearing resistance and joint flexibility of seam connections, cladding/purlin connections and purlin/rafter connections. The novel aspects of the experimental research include investigation of the behaviour of shear connections in 0.5mm thick sheeting and thick-to-thin connections in S550 high tensile steel. Overall, six series of tests were conducted and each test was repeated five times in order to demonstrate …


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 Nov 2018

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 Nov 2018

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 Nov 2018

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 Nov 2018

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 Nov 2018

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 Nov 2018

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 …


Influence Of Gypsum Panels On The Response Of Cold-Formed Steel Framed Strap-Braced Walls, Sophie Lu, Colin A. Rogers Nov 2018

Influence Of Gypsum Panels On The Response Of Cold-Formed Steel Framed Strap-Braced Walls, Sophie Lu, Colin A. Rogers

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

In cold-formed steel construction the steel frame is supplemented with either diagonal strap braces or structural sheathing panels (typically steel or wood) to provide overall stability to the structural system and to directly transfer lateral wind and seismic loads through to the foundation as per the design provisions found in AISI S240 (2015) and AISI S400 (2015). Gypsum panels are often specified to provide a fire-resistance rating for the CFS frame, as well as to ensure that adequate sound-proofing exists between adjacent rooms or building units. The engineer may choose to rely on this gypsum to provide additional lateral resistance, …


Human-Structure Interaction In Cold-Formed Steel Floor Systems: An Analytical Perspective, Sigong Zhang, Lei Xu Nov 2018

Human-Structure Interaction In Cold-Formed Steel Floor Systems: An Analytical Perspective, Sigong Zhang, Lei Xu

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

Designing cold-formed steel (CFS) floors to prevent annoying vibrations induced by human activities such as walking is still a challenge because human occupants not only generate impact loads but also behave as dynamical systems that interacting with structures. Such interaction, known as human-structure interaction (HSI), can be significant for lightweight floor systems particularly for the case when the mass of human occupants becomes comparable to those of the floors. The aim of this study was therefore to investigate the HSI in vibration of CFS floors subjected to human walking excitations by using the recently proposed damped plate-oscillator model to predict …


New Web Crippling Design Rules For Cold-Formed Steel Beams, L. Sundararajah, M. Mahendran, P. Keerthan Nov 2018

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 …


Design Of Rivet Fastened Rectangular Hollow Flange Channel Beams Subject To Local Buckling, L. Sundararajah, M. Mahendran, P. Keerthan Nov 2018

Design Of Rivet Fastened Rectangular Hollow Flange Channel Beams Subject To Local Buckling, L. Sundararajah, M. Mahendran, P. Keerthan

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

The innovative, rivet fastened Rectangular Hollow Flange Channel Beam (RHFCB) is a new type of cold-formed steel section, proposed as an extension to the widely researched hollow flange beams. The hollow flange beams have garnered much interest in the past due to the sections having capacities more typically associated with hot-rolled steel sections. Various researches have been carried out to investigate the behavior of continuously welded hollow flange beams but little is known on the behavior of RHFCBs. The structural behaviour of the RHFCB is unique compared to other conventional cold-formed steel sections and its moment capacity reduces with rivet …


Web Crippling Of Cold-Formed High Strength Steel Square And Rectangular Hollow Sections Under Two-Flange Loading Conditions, Hai-Ting Li, Benjamin Young Nov 2018

Web Crippling Of Cold-Formed High Strength Steel Square And Rectangular Hollow Sections Under Two-Flange Loading Conditions, Hai-Ting Li, Benjamin Young

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

The web crippling behavior of cold-formed high strength steel (HSS) square and rectangular hollow sections under End-Two-Flange and Interior-Two-Flange loading conditions is studied. The cold-formed HSS tubular sections had nominal 0.2% proof stresses of 700 and 900 MPa. Finite element (FE) models were developed and validated against test results, showing the capability of replicating the experimental web crippling strengths, failure modes and load-deformation histories. Upon validation of the FE models, an extensive parametric study comprised 112 FE analyses was performed. The web crippling strengths obtained from the experimental and numerical investigations were compared with the nominal strengths calculated from the …


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 Nov 2018

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 …


Study On Distortional Buckling Of Cold-Formed Stainless Steel Beams, Shuang Niu, Zhidong Zhang, Feng Fan Nov 2018

Study On Distortional Buckling Of Cold-Formed Stainless Steel Beams, Shuang Niu, Zhidong Zhang, Feng Fan

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

In the current research, distortional buckling of cold-formed stainless steel open-section beams was investigated. Four-point bending tests of eight C-section stainless steel beams, made of S30401 alloy, were carried out with global and local buckling precluded by careful design of specimen and test rigs. A detailed finite element model based on ABAQUS was developed and verified against test data. Parametric study was carried out with the verified model, covering four types of sections (C, Z, SupaCee, and SupaZed), three stainless steel alloys (S30401, S44330, S32101), and a series of section slenderness. A convenient method to identify distortional buckling point in …


Flexural Strength Of Continuous-Span Z-Purlins With Paired Torsion Braces Using The Direct Strength Method, Michael Seek Nov 2018

Flexural Strength Of Continuous-Span Z-Purlins With Paired Torsion Braces Using The Direct Strength Method, Michael Seek

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

A procedure is presented to calculate the local and distortional flexural buckling strength of continuous span purlins with paired torsion braces using the Direct Strength Method. Displacement compatibility is utilized to determine the forces interacting between the purlin, the flexible diaphragm and the torsion braces. The biaxial bending and torsion effects caused by this interaction are superimposed, and the actual distribution of stresses within the cross section are calculated at critical locations along the span. With this distribution of stresses, a finite strip buckling analysis is performed to determine the local and distortional buckling strength. In current design practice, results …


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 Nov 2018

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 Nov 2018

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 Nov 2018

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. …


Bearing Strength Of Untightened Double-Shear Bolted Connections In Cold-Formed Steel Construction, Refat Bhuiyan, Lip H. Teh Nov 2018

Bearing Strength Of Untightened Double-Shear Bolted Connections In Cold-Formed Steel Construction, Refat Bhuiyan, Lip H. Teh

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

This paper presents the experimental investigation of cold-formed steel double-shear bolted connections where both the bolt head and the nut are not in contact with the outer sheets. The inner sheet of each specimen is not constrained from out-of-plane distortion or bulging downstream of the bolt, and fails in bearing. Based on a series of tests involving specimens having bolt diameters ranging from 12 to 16 mm and sheet thicknesses ranging from 1.5 to 3.0 mm, it has been found that the absence of out-of-plane constraint in untightened bolted connections leads to much lower bearing capacities than predicted by the …


Sdi Steel Deck On Cold-Formed Steel Framing Design Manual, Thomas Sputo Nov 2018

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 Nov 2018

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 …


Biaxial Bending Of Cold-Formed Steel Storage Rack Uprights – Part Ii: Design Methods, Nima Talebian, Benoit P. Gilbert, Cao Hung Pham, Hassan Karampour Nov 2018

Biaxial Bending Of Cold-Formed Steel Storage Rack Uprights – Part Ii: Design Methods, Nima Talebian, Benoit P. Gilbert, Cao Hung Pham, Hassan Karampour

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

This paper uses the results from the parametric studies reported in the companion paper to verify the accuracy of different forms of published direct strength method (DSM) equations. They consist of the classical DSM equations and considering the inelastic reserve capacity into these equations, with and without an extended range of the cross-sectional slenderness. The verifications are made for local and distortional buckling modes. Results show that for all investigated buckling modes, the DSM results in better predictions when the inelastic reserve capacity is considered. The appropriate form of the DSM to predict the biaxial capacity of unperforated cold-formed steel …


Finite-Element Analysis Of The Eaves Joint Of Cold-Formed Steel Portal Frames Having Single Channel-Sections, Pouya Pouladi, John Ronaldson, George Charles Clifton, Jason Maxwell Ingham, Andrzej M. Wrzesien, Paul Milewski, James B. P. Lim Nov 2018

Finite-Element Analysis Of The Eaves Joint Of Cold-Formed Steel Portal Frames Having Single Channel-Sections, Pouya Pouladi, John Ronaldson, George Charles Clifton, Jason Maxwell Ingham, Andrzej M. Wrzesien, Paul Milewski, James B. P. Lim

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

A finite element model is described for the eaves joint of a cold-formed steel portal frame that comprises a single channel section for the column and rafters eaves connections. The members are connected to the brackets through both screws and bolts. Such a joint detail is commonly used in practice in New Zealand and Australia, where the function of the screws is to prevent slip of the joint during frame erection since the bolt holes are detailed for nominal clearance. The results of the finite element model are compared against two experimental test results. In both, the critical mode of …


Influence Of Fire On The Shear Capacity Of Cold-Formed Steel Framed Shear Walls, M. S. Hoehler, B. Andres Nov 2018

Influence Of Fire On The Shear Capacity Of Cold-Formed Steel Framed Shear Walls, M. S. Hoehler, B. Andres

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

This paper presents experimental investigations of the performance of common lateral force-resisting systems used in cold-formed steel construction under sequential thermal (fire) and mechanical (earthquake) loading. Wall specimens with gypsum-sheet steel composite sheathing, Oriented Strand Board (OSB) sheathing, or steel strap bracing were tested. The results demonstrate that the lateral capacity of wall systems can be reduced by exposure to fire. Additionally, fire performance of wall systems can be affected by pre-damage to the fire-resistive components that provide fire protection to these walls. The results are useful for fire compartmentation design when significant lateral deformation of a building is anticipated …


Finite Element Modeling And Validation Of Steel Sheathed Cold-Formed Steel Framed Shear Walls, Amanpreet Singh, Tara C. Hutchinson Nov 2018

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 …


Performance Of Cold-Formed Steel Shear Walls With Frame Blocking And Double-Sheathing, Robert Rizk, Vincent Briere, Veronica Santos, Colin A. Rogers Nov 2018

Performance Of Cold-Formed Steel Shear Walls With Frame Blocking And Double-Sheathing, Robert Rizk, Vincent Briere, Veronica Santos, Colin A. Rogers

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

This paper summarizes a laboratory based research program on blocked and double-sheathed cold-formed steel framed shear walls. The intent was to develop walls whose in-plane shear resistance exceeds that of configurations currently listed in the AISI S400 Standard. The results showed that the frame blocking can be used in the construction of walls whose resistance is at the limit of that found in AISI S400; however, the blocking will not adequately restrain the framing members if thicker sheathing is used. An approach was needed to minimize the effect of the eccentric loading caused by the sheathing and to account for …


Aggie Marine Robotics Club Works On New Designs For Autonomous Submarine | College Of Engineering, Usu College Of Engineering Nov 2018

Aggie Marine Robotics Club Works On New Designs For Autonomous Submarine | College Of Engineering, Usu College Of Engineering

College of Engineering News

The TIJAR perches on the edge of the desk, becoming smarter and more efficient by the day.


Sub-Pilot-Scale Autocatalytic Pyrolysis Of Wastewater Biosolids For Enhanced Energy Recovery, Zhongzhe Liu, Simcha L. Singer, Daniel Zitomer, Patrick J. Mcnamara Nov 2018

Sub-Pilot-Scale Autocatalytic Pyrolysis Of Wastewater Biosolids For Enhanced Energy Recovery, Zhongzhe Liu, Simcha L. Singer, Daniel Zitomer, Patrick J. Mcnamara

Civil and Environmental Engineering Faculty Research and Publications

Improving onsite energy generation and recovering value-added products are common goals for sustainable used water reclamation. A new process called autocatalytic pyrolysis was developed at bench scale in our previous work by using biochar produced from the biosolids pyrolysis process itself as the catalyst to enhance energy recovery from wastewater biosolids. The large-scale investigation of this process was used to increase the technical readiness level. A sub-pilot-scale catalytic pyrolytic system was constructed for this scaled-up study. The effects of configuration changes in both pyrolytic and catalytic reactors were investigated as well as the effect of vapor-catalyst contact types (i.e., downstream, …