Engineering Commons^™

Lateral-Torsional Buckling Of General Cold-Formed Steel Beams, Robert S. Glauz

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

The design of unbraced cold-formed steel beams must consider lateral-torsional buckling due to the low torsional stiffness associated with open cross-sections. The American Iron and Steel Institute incorporated design equations for the critical elastic lateral-torsional buckling stress in the North American Specification for the Design of Cold-Formed Steel Members. These equations are based on elastic theory for singly-symmetric and doubly-symmetric sections. However, the equation for point-symmetric sections is only a rough approximation. Furthermore, there are no provisions for lateral-torsional buckling of non-symmetric sections, or sections oriented to non-principal axes. This paper investigates and develops a general formulation of the lateral-torsional …

Unconstrained Cross-Sectional Shape Optimisation Of Cold-Formed Steel Beams And Beam-Columns, Bin Wang, Benoit P. Gilbert, Guillaume L. Bosco, Hong Guan, Lip H. Teh

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

This paper is focused on optimising the cross-sectional shapes of simply-supported, singly-symmetric and open-section cold-formed steel (CFS) beams and beam-columns without manufacturing or assembly constraints. A previously developed Genetic Algorithm (GA) is used in this study. Fully restrained and unrestrained beams against lateral deflection and twist, as well as unrestrained beam-columns are optimised, of which the nominal member capacities are determined by the Direct Strength Method (DSM). The optimised cross-sectional shapes are presented and the evolution of the unrestrained cross-sectional shapes for various combinations of axial load and bending moment is analysed and discussed.

Identifying Shear Buckling Coefficients For Channels With Rectangular Web Stiffeners Using The Generalised Cfsm, Morgan A. Rendall, Gregory J. Hancock, Kim J. R. Rasmussen

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

The Direct Strength Method (DSM) of design for cold-formed sections was recently extended in the North American Specification for Cold-Formed Steel Structural Members (NAS S100:2012) to include members in shear. The method has largely been developed on the basis of work done on lipped channel sections. To utilise the method requires the critical shear buckling load of the section, which may be determined from a minimum point on the signature curve for the section in pure shear. However when longitudinal web stiffeners are added to the channel a minimum may not exist, or may occur at half-wavelengths where the critical …

A Direct Strength Method (Dsm) Of Design For Channel Sections In Shear With Square And Circular Web Holes, Song Hong Pham, Cao Hung Pham, Gregory J. Hancock

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

The Direct Strength Method (DSM) design rules for cold-formed steel members in shear have been incorporated recently into the North American Specification (AISI S100-12) and are being implemented in the Australian standard (AS/NZS 4600:2005). The method, which was calibrated for unperforated members only, requires two inputs including the buckling load Vcr and the shear yielding load Vy. For members with square web cut-outs, Vcr can be computed by either the Spline Finite Strip Method (SFSM) or the tabulated values based on the shear buckling coefficients kv as studied by CH Pham or the Finite Element Method (FEM). However, Vy has …

New Sdi Diaphragm Design Manual, Larry Luttrell, John Mattingly, Walter Schultz, Thomas Sputo

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

The Steel Deck Institute (SDI) has released the new and long awaited 4th Edition of the Diaphragm Design Manual (DDM04). This new edition complies with the requirements of the ANSI/AISI S310-13 North American Standard for the Design of Profiled Steel Diaphragm Panels. At 408 pages, the 4th Edition is larger than its predecessor and will be an invaluable resource to structural designers because of the background information, design examples, and extensive load tables.

The First Edition of the DDM, published in 1981, was authored by Dr. Larry Luttrell, P.E., the Technical Advisor to the SDI. The diaphragm design method developed …

Recent Developments In The Australian/New Zealand Standard As/Nzs 4600 For Cold-Formed Steel Structures, Gregory J. Hancock

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

The Australian/New Zealand Standard AS/NZS 4600 is currently under revision based in part on the latest edition of the North American Specification AISI S100:2012 and partly based on the latest research in Australia and New Zealand. The Direct Strength Method (DSM) of design has undergone substantial research since the 2005 edition of AS/NZS 4600 and this research is now incorporated in the revised edition. The new areas in the DSM include shear, combined bending and shear, combined bending and compression, sections with holes and inelastic reserve capacity. Further, the prequalified sections now include most sections with longitudinal web and flange …

Progress In The Development Of Asce 41 For Cold-Formed Steel, Deniz Ayhan, Robert L. Madsen, Benjamin W. Schafer

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

The objective of this paper is to document progress on new cold-formed steel provisions for the forthcoming edition of ASCE 41, Seismic Evaluation and Retrofit of Existing Buildings. The current edition of ASCE 41 (2013) is weak with respect to the application of cold-formed steel and provides only limited information on cold-formed steel framed buildings, shear walls, members, and connections. The emphasis in this paper is on cold-formed steel framed shear walls, and the development of modeling parameters that characterize the backbone shear-deformation response, and acceptance criteria that provide allowable demand-to-capacity ratios (m-factors) for the shear walls based on a …

Aisi Standards Developed And Updated In 2015 And 2016, Helen Chen, Roger Brockenbrough, Richard Haws

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

During 2015 and 2016, AISI developed framing standards were consolidated and updated, the North American Specification was updated and reorganized in format, and two new test standards were published. This paper provides an overview of the reorganized standards and major changes, and a brief introduction to the newly developed test standards.

Advancing Bim For Cold-Formed Steel Structures, Adam Johnson, Roni Ramirez, Cheng Yu

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

This paper presents a research project aimed at advancing BIM for cold-formed steel (CFS) structures. The creation of the CFS family for Autodesk Revit is a handy solution for the lack of CFS members and information inside the Autodesk Revit libraries. Revit is one of the industry’s standard software for producing building information models. To overcome the disadvantages of not having CFS members in Revit, this research project focused on two phases to reach completion. Phase one consisted of developing a BIM library of industrial standard CFS members such as studs, tracks, and channels. Parameters were added to the members …

The Design And Development Of New Cold Roll Formed Products By Finite Element Modeling And Optimisation, V. B. Nguyen, P. K. C. Wood, M. A. English, M. A. Castellucci

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

The design and development of new cold roll formed products can incur significant cost and the product may not be optimised for either performance or manufacture. This paper describes a new method to develop an optimum structural design of profile by cold roll forming using a combined approach of finite element analysis and optimisation techniques. To illustrate the concept, the design and development of a new channel beam and a new drain grating subjected to bending are presented. The two case studies, demonstrate how a roll formed profile may be optimised to improved structural performance through use of stiffeners and/or …

Buckling Strength Of Cold-Formed Circular Steel Column Subjected To Axial Load, Ayana Ito, Nobutaka Shimizu, Keiichi Sato, Yoshimichi Kawai

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

In this study, the global buckling behavior of a cold-formed circular steel column was discussed with a focus on the effects of its mechanical properties and initial imperfections on the behavior. As the first step, the stress–strain curves of the column under tensile and compressive loads as well as its residual stresses were investigated. Subsequently, a finite element analysis was conducted to clarify if the analysis properly simulated the stub column behavior. The analysis results obtained using measured compressive stress–strain curves and residual stresses agreed well with experimental results. Finally, another finite element analysis was performed on the long column …

Proposal For Codification Of A Dsm Design Approach For Cold-Formed Steel Short-To Intermediate Angle Columns, Pedro Borges Dinis, Dinar Camotim

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

This paper presents a proposal for the codification of an efficient design approach for cold-formed steel short-to-intermediate equal-leg angle columns, consisting of a slight modification of a design approach developed by Dinis & Camotim (2015) and based on the Direct Strength Method (DSM). After (i) collecting the available experimental and numerical failure load data, comprising fixed-ended and pin-ended columns with several geometries (cross-section dimensions and length) and reported by various researchers, and (ii) briefly reviewing the mechanical reasoning behind the proposed procedures, the search for new/simpler expressions to provide the DSM design curves is addressed. Their merits are assessed through …

Effect Of Web Perforation On The Behaviour Of Cold-Formed Steel C-Shape Slender Column Subjected To Non-Uniform Cross-Sectional Distribution Of Elevated Temperatures, S. Yang, L. Xu

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

Presented in this paper is a numerical investigation on the effect of web perforations on the behaviour of cold-formed steel C-shape columns subjected to non-uniform cross-sectional distribution of elevated temperature with use of finite element analysis. The length of web perforation investigated varies from 0 mm to 630 mm (25 in.). The non-uniform cross-sectional distributions of elevated temperatures are obtained from finite element thermal analysis of insulated CFS walls subjected to standard fire up to 105 minutes. Sequentially coupled thermal-stress analyses were carried out under a transient state condition. The concentrically loaded cold-formed steel C-shape columns with load ratios of …

Distortional Buckling Experiment On Cold-Formed Steel Lipped Channel Columns With Circle Holes Under Axial Compression, Xingyou Yao, Yanli Guo, Zhen Nie

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

The objective of this paper is to research the distortional buckling mode and load-carrying capacity of cold-formed thin-walled steel columns with circle holes in web. Compression tests were conducted on 26 intermediate length columns with and without holes. The test members included four different kinds of circle holes. Test results show that the distortional buckling occurred for intermediate columns with holes and the strength of columns with holes was less than that of columns without circle hole. The ultimate strength of columns decreased with the increase of the total transverse width of hole in cross-section of members. For each specimen, …

Dsm For Web Crippling Under Two-Flange Conditions, Pedro Natário, Nuno Silvestre, Dinar Camotim

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

This paper summarizes recent investigations on the development of Direct Strength Method (DSM) for the design of cold-formed steel beams under two-flange (TF) loading against web crippling failure. Recently, the authors proposed a new approach to predict the web crippling failure load of cold-formed steel beams under External Two Flange (ETF) and Internal Two Flange (ITF) loadings using DSM. Firstly, existing experimental test data are summarized and then the accuracy of North-American Specification (AISI 2012) and Eurocode 3 (CEN 2006) provisions is briefly assessed. In order to obtain additional information on the web crippling behavior of each test specimen, non-linear …

Experimental Investigation Of Cold-Formed C-Sections With Central Square Holes In Shear, Cao Hung Pham, Andreas Pelosi, Thomas Earls, Gregory J. Hancock

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

The North American Specification S100:2012 Edition has recently included DSM design rules for unperforated channel sections in shear. However, there are no rules presented in this standard for the DSM in shear for sections with holes. Recently, a testing program has been performed at the University of Sydney to determine the ultimate strength of high strength cold-formed C-sections with a thickness of 1.5 mm and central square holes of varying sizes. Three different sizes of the square holes were chosen for testing. For thin sections, the DSM shear curve was found to be applicable for design of sections with square …

The Effects Of The Stratosphere On Materials, Ashley C. Greene, Theresa M. Palandro

Posters-at-the-Capitol

Abstract 1:

Making AND Breaking: How reliable are some water pipes?

Ashley C. Greene.

Three different types of pipes were tested to see at what point in time they would break. The pipes, PVC pipe, PEX pipe, and CPVC pipe, were filled with water and attached to a helium filled weather balloon. The ends of the pipes were sealed to trap the water inside. The pipes were secured onto a payload in a Styrofoam box surrounded by cheese cloth. This frame secured the pipes and ensured that they stayed in one place and could not move around the container. The …

High Altitude Ballooning And The Effect Of Temperature On Balloon Ascent Rate, Christopher D. Young

Posters-at-the-Capitol

Abstract

High Altitude Ballooning and The Effect of Temperature on Balloon Ascent Rate.

Christopher Young

High-altitude balloons are unmanned balloons, usually filled with helium or hydrogen, that after release, ascend into the stratosphere, generally attaining an altitude of between 60,000 to 100,000 feet. The balloon payload includes scientific experiments on organisms, equipment to study radiation, temperature, ultra- violet radiation, and pressure. The balloon flights and experiments are logged by means of video devices and are tracked from the ground through multiple tracking devices. The effect of temperature on the ascent rate of the balloon could change how the balloon expands …

Model Truss Bridge Design, William Spicer Berry, Kaleb Rankin Dyer, Dustin Lee Schultz

Posters-at-the-Capitol

Bridges are one of the most important and costly engineering projects, involving extensive design considerations that try to minimize expenses while insuring the bridge will not fail. Different models of bridges were constructed in order to perform experiments that determined which beams were in compression and how much force was experienced in the beam’s when a static load was applied. Computer simulations were also performed to determine the loads on the different beams. The simulation and calculated results were compared to ensure accuracy of the final results. It was determined that a Howe bridge offers the lowest maximum compression on …

"Feasibility Of Efficient Photovoltaics In Eastern Kentucky" / "Developing A 3-D Printed Solar Vehicle With Computational Fluid Dynamics (Cfd) Simulator", Adam N. Stanley, Matthew R. Hezseltine

Posters-at-the-Capitol

Abstract 1

Feasibility of Efficient Photovoltaics in Eastern Kentucky

Photovoltaics (PV-also called solar photovoltaic devices) are used to harness the power of the sun via the electronic process that occurs within semiconductor cells. The solar energy is absorbed by the cells, which causes the electrons to break away from their atoms, allowing them to flow within the material to produce electricity. This electricity will become the renewable energy for Kentucky, as the generation of coal will but come to a stop within the near future. Like Denmark who is running on 100% renewable generation we must stride to become fully …

Eastern Kentucky University's Program Of Distinction: Highlighting Research Within The Colege Of Justice And Safety, Naomi M. Sigler, Kayla Tunajek

Posters-at-the-Capitol

Posters at the Capitol 2016-2017 Abstract

University: Eastern Kentucky University – College of Justice & Safety

Program: Fire, Arson, and Explosion Investigation

Student Presenters: Kayla Tunajek and Naomi Sigler

Faculty Mentor: Paul Grant

Title: Eastern Kentucky University’s Program of Distinction: Highlighting Research within the College of Justice and Safety

Keywords: Program of Distinction; Eastern Kentucky University; fire programs; research projects; student opportunities.

ABSTRACT

This project is intended to represent the Program of Distinction at EKU. The fire program at Eastern provides students several unique majors and encourages students to do research within their respective fields. This research is then presented …

Cricketsat: Space Temperature Measurement Module, Mitchell I. Harris, Saeed Almalki

Posters-at-the-Capitol

The CricketSat Project at Murray State University was developed to establish better understandings for the design and assembly procedures of satellite technology. The satellite consists of one remote sensor that provides specific frequencies corresponding to various temperatures. By purchasing this inexpensive CricketSat, it provides students with the opportunity to advance their understanding of satellite technology and partake in hands on learning.

The CricketSat is composed of a single wireless module and a receiving antenna. The sensor transmits an audio tone that changes frequency in response to temperatures within the atmosphere. During launch, the CricketSat is attached to a helium balloon …

C-3 Examination Of Anodized Aluminum For Surface Defects After Thermal Cycles, Boon-Chai Ng

Celebration of Research and Creative Scholarship

A major cost in the fabrication of test sockets is the interposer, an interface layer that reroutes one connection to another. The interposer must have high resistivity with low loss, a smooth surface finish, high strength, resistance to chemicals involved in the process, and be extremely thin. Currently, the most common materials used for interposer are plastics, such as Torlon, Semitron, and PEEK. While these satisfy the requirements for test sockets, they do not perform well under higher ambient temperatures. Finding a less expensive, alternative material would be preferable.

In this study, anodized aluminum samples were subjected to repeat thermal …

Green Energy Or Nuclear Power Plants, Besnik Skenderi, Diamanta Skenderi

UBT International Conference

World seems to go green regarding the energy, however the cost of green energy is high and as a result of security issues nuclear energy seems to be avoided, while introducing business and outsourcing concepts nuclear energy seems to be solution.

The Design Of An Extradosed Bridge, Drilon Rraci, Milan Kuhta

UBT International Conference

Bridges are attractive structures consisting of great interest in both aspects: professional and the general public one. At the end of 19. and start of 20. century, one of the most relevant contributions to bridges engineering has been the introduction of prestressed technique, aiming to be a great solution to the need of controlling stress on elements in bridges. The purpose of this paper is to discuss and analyze the design model and structural behavior of an Extradosed bridge. The strategies and factors that must be considered in the design of an Extradosed bridge are included in this paper. The …

Assessment Of Reinforced Concrete Half Joint According To En -1992-1-1, Xhemshir Mulliqi

UBT International Conference

A half-joint is a particular type of RC structure .When using precast beams in reinforced concrete frame structures, dapped beams ends are often required in the bearing area to keep the floor structure as thin as possible. The arrangement and detailing of the reinforcement is an important factor in the performance of a half-joint. For pre-tensioned members, the prestressing force and tendons should be ignored, but for post-tensioned members the prestressing force should be considered as an external force acting on the half-joint. This paper aims to calculate dapped beam ends according to the EN 1992-1-1.

Effects Of Sustainable Materials In Construction, Environment And Health, Muhamet Ahmeti, Mimoza Sylejmani, Vlora Aliu

UBT International Conference

In this paper it is presented a definition of sustainable construction from ecological aspect, characterized by reducing the impact of different materials in the environment during construction, but also during the whole lifetime of use of buildings. To assess the impact of materials on health and environment is necessary to examine all phases from beginning of the materials manufacturing till the insertion to the construction, including the use of natural resources for the production of construction products, necessary energy for production, amount of release and CO2 emissions (carbon dioxide) in different stages, methods of construction, use of construction and in …

Radial Structure Graph Based Mathematical For Large Distribution Networks, Ines Bula, Valmir Hoxha, Edin Bula

UBT International Conference

In the modern electrical distribution network and utility companies a steady increase in the need for high quality and safe delivery of electricity to consumers is evident, which requires an adequate distribution network, that is a network with high quality voltage and low loss of energy, with a small number of failures and equipment failure , etc. In this paper is proposed a way of representing the mathematical model of distribution networks. For calculations of energy applications, the best way for representation distribution network is in form of graph of the radial structure. By presenting the distribution network in the …

The Neutralization Of Water Polution, Afrim Osmani

UBT International Conference

One of the biggest sources of pollution land and water are industrial waste waters. At section of zinc industry in complex Trepca during the process of zink production acquire(are gained or obtained) wastewater where their negative impact is wider extent of contamination of land with which it comes in contact and in this case comes to the accumulation ions of heavy metals, surface water and then mixing with groundwater and pollution. Directly with vulnerable is Sitnica river, in which contaminated water flows from the industrial unit for the production of Zn, which flows into the Ibar river, which still flows …

General Concept For Strengthening The Reinforced Concrete Column A Wrapping Of Cf Sheet, Florim Istrefi

UBT International Conference

Fiber reinforced polymer (FRP) composites (the combination of two or more materials). Used more often in the defense and aerospace industries, advanced composites are beginning to play the role of conventional materials (commodities) used for load-bearing structural components for infrastructure applications. These unique materials are now being used worldwide for building new structures as well as for rehabilitating in-service structures.

“FRP” is an acronym for fiber reinforced polymers, which some also call fiber reinforced plastics, so called because of the fiber content in a polyester, vinyl ester, or other matrix. Three are commonly used (among others): composite containing glass fibers …