Engineering Commons^™

Further Studies Of Composite Slab Strength, Angela S. Terry, Samuel W. Easterling

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

The results to date of a research program focusing on the strength of composite slabs are described. Full-scale experimental slab tests are compared to strengths calculated using the Steel Deck Institute Composite Deck Design Handbook. Based on the comparisons, recommendations are made for modifications to the calculation procedures.

Review Of Concepts Concerning Bond Of Steel Decking, Mark Patrick, Russell Q. Bridge

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

It is well established that bond between deformed reinforcing bars and concrete is produced by three distinct actions: chemical adhesion; friction; and mechanical interlock. However, researchers of composite slab behaviour do not generally agree on the actions which produce bond between steel decking and concrete, and the concepts they have developed in this regard are reviewed.

Local Buckling Of Filled Sections, Howard D. Wright

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

The buckling capacity of plates in contact with a rigid medium is greater than that for free plates. Such plates occur in sections filled with a suitably stiff material. Classical analysis is used to compare restrained and free plates.

Tests Of Thin-Walled Concrete-Filled Steel Tubes, Martin D. O'Shea, Russell Q. Bridge

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

Concrete filled tubes are likely to be economical with the use of very high strength concretes and thin-walled steel tubes. The strength of the steel tube is affected by local buckling effects which may also influence the confinement to the concrete infill. Very high strength concretes exhibit rapid unloading in the post-ultimate region. The strength of the composite column is not a simple superposition of strengths of the individual steel and concrete components. This paper describes the initial tests of an experimental program to determine the effects of local buckling on concrete filled tubes. Tubes with a diameter to wall …

Design Of A Purlin System, C. Jiang, D. St. Quinton

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

This paper is concerned with the design of cold-formed steel structural members which span between the frames of a building and carry cladding which is usually either single- or double-skin profiled metal sheeting or a sandwich panel. The cladding is fIxed to these purlins or sheeting rails at regular intervals and the performance in service, and therefore the design, is strongly influenced by interaction with the sheeting. The connection between the purlins and the supporting structure also has a significant influence on performance so that, historically, the emphasis has tended to be on empirical methods of design rather than detailed …

Light-Gauge Engineering In Today's Marketplace - The Challenges, Gene Farach, Robert C. Grupe Jr.

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

Light-gauge has tremendous potential in the construction industry. It is a material which affords more carrying capacity per less weight. Thus less material needs to be used which leads to a reduction in labor and subsequent reduction in cost, light-gauge is a durable, recyclable product, environmentally friendly in keeping with today's concern for the world around us. It is resistant to insects such as termites, mold mildew, rotting, drying out, warping and non combustible. However the reality remains that if research and development is not undertaken soon, the window of current demand may be short lived. We must accept that …

Comparison Of A Non-Linear Purlin Model With Tests, Catherine J. Rousch, Gregory J. Hancock

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

A non-linear elastic analysis has been developed for determining the lateral deflections of, and stresses in, the unconnected flanges of simply-supported and continuous channel and Z-section purlins screw-fastened to sheeting and subject to either wind uplift or gravity loading. The analysis incorporates a model, based on a combination of those developed by Pekoz and Soroushian, and Thomasson, which depicts the unconnected purlin flange as a beam-column. The restraint against lateral deflection is provided primarily by the sheeting, and is represented by a linear extensional spring of stiffness k located at the level of the unconnected purlin flange. To verify the …

Reference Section Method For Local Web Buckling, T. K. Sooi, Reynaud Serrette, Teoman Pekoz

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

The present AISI effective width approach for determining flexural section capacities of sections with slender webs requires an iterative approach. A simplified method, called the Reference Section Method or RSM, which eliminates the need for iteration is presented and discussed. The reference section is defined as one that is similar to the actual section except for the web height. This simplified method is based on the premise that the flexural capacity of a section with slender webs is proportional to that of a reference section with compact web. The ratio of the web height of the actual section to that …

Flexural Capacity Of Continuous Span Standing Seam Panels: Gravity Load, Reynaud Serrette, Teoman Pekoz

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

The standing seam panel is one of the most practical and economical roofing systems developed in recent years. Construction of the roof system requires that the panel legs be overlapped and crimped. Under gravity load, the crimped outstanding leg of the connected panels may be subject to distortional buckling. A design method was previously suggested for estimating the distortional buckling strength of the outstanding leg of a single simply supported standing seam panel. In this paper, an approximate method is present for estimating the capacity of a system of interconnected continuous span standing seam panels. Experimental results for three full-scale …

Cold-Formed Steel Sections For Transmission Towers, David Odaisky, Dimos Polyzios, Glenn Morris

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

Hydro-electric transmission towers are traditionally built using hot-rolled angles. However cold formed angles are becoming more popular as replacements for hot-rolled angles, especially in the smaller angle sizes. In addition to conventional 90° angles, a wide range of shapes can be produced, in sizes to suit individual project requirements. In particular, cold-forming can be used to provide stiffening lips to prevent local buckling of thin wide elements, to optimize shapes so that longer unbraced lengths can be used, and to create shapes such as 60° angles for triangular towers. A research project was carried out at the University of Manitoba …

Stub Column Study Using Welded, Cold-Reduced Steel, L. Randy Daudet, K. H. Klippstein

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

The primary goal of the subject study was to investigate the behavior and load capacity of stub columns using cold-reduced, low-ductility steel versus un-reduced, normal-ductility steel. Specimens that were cold-reduced were also welded transversely across the entire stud cross section. Therefore, this study also yielded data with regard to the axial performance of welded studs. In addition, since stub columns were punched and un-punched, further conclusions can be drawn about the effect of a weld located at a web perforation. A total of 133 stub column tests were performed at the Dietrich Material Testing Laboratory in Hammond, Indiana, between December …

Minimization Of Generalized Reed-Muller Expansion And Its Sub-Class, Xiaoqiang Zeng

Dissertations and Theses

Several classes of AND-EXOR circuit expressions have been defined and their relationship have been shown. A new class of AND-EXOR circuit, the Partially Mixed Polarity Reed-Muller Expression(PMPRM), which is a subclass of the Generalized Reed-Muller expression, is created, along with an efficient minimization algorithm. This new AND/EXOR circuit form has the following features: • Since this sub-family of ESOP (with a total of n2n-I22n-i - (n-1)2n forms which includes the 2n Fixed-Polarity Reed-Muller forms) is much larger than the Kronecker Reed-Muller(KRM) expansion(with 3n forms), generally the minimal form of this expansion will be much closer to the minimal ESOP than …

High Strength Alumina And Process For Producing Same, James M. Staehler, William W. Predebon, Bruce J. Pletka

Michigan Tech Patents

A vacuum hot pressed alumina material having small, isometric grains; a uniform distribution thereof; relatively low, predominantly transgranular porosity; and a density approaching the theoretical density of pure alumina produced by vacuum hot pressing alumina powder which contains at least 98.0% alumina, is substantially free of any sintering aids or any other additives, and has a median particle size less than about 3 microns, in a vacuum hot press operated at a temperature of at least about 1350° C. and a pressure of at least 28 MPa (3500 PSI) for a sintering period of at least 1.5 hours. The vacuum …

Reflection And Refraction Of Light From Nonlinear Boundaries, Mohammad Azadeh

Dissertations and Theses

This thesis deals with the topic of reflection and refraction of light from the boundary of nonlinear materials in general, and saturating amplifiers in particular. We first study some of the basic properties of the light waves in nonlinear materials. We then develop a general formalism to model the reflection and refraction of light with an arbitrary angle of incidence from the boundary of a nonlinear medium. This general formalism is then applied to the case of reflection and refraction from the boundary of linear dielectrics. It will be shown that in this limit, it reduces to the well known …

Characterization Of The Near-Interface Region Of Chemical Vapor Deposited Diamond Films On Silicon By Backscatter Kikuchi Diffraction, Brent L. Adams, K. Kunze, S. Geier, R. Hessmer, M. Schreck, B. Rauschembach, B. Stritzker

Faculty Publications

The lattice orientations near the interface of chemical vapor deposited diamond films on Si(001) have been studied by orientation imaging microscopy. This technique is based on the automated analysis of electron backscatter Kikuchi diffraction patterns. The electron beam has been scanned in discrete steps over the reverse side of the diamond film after having removed the substrate. The obtained data have allowed us to determine the texture and to visualize quantitatively the orientational arrangement of and among individual diamond crystallites in the near-interface region. A comparison with the orientation of the substrate has proved the existence of epitaxially nucleated grains. …

Behavior Of Concrete And Slender Reinforced Concrete Columns Under Cyclic Axial Compression With Bidirectional Eccentricities, Byong Youl Bahn

Dissertations

A rational analysis of reinforced concrete (R/C) structures requires satisfactory modeling of the behavior of concrete under general loading patterns. The behavioral characteristics of concrete dominantly depends upon its load history. For the study of concrete behavior, parametric study and experimental investigation into the behavior of concrete under load history of random cycles are performed. Through parametric study, the applicability of the previous concrete models is examined and a physically motivated modeling for the cyclic stress-strain relationships is proposed. The present modeling of concrete under general cyclic loading is initiated to provide substantial applicability, flexibility of mathematical expressions and furthermore …

Theoretical Evaluation Of The Break Off Test For Concrete, Arjuna Priyara Ranasinghe

Dissertations

Strength of concrete is normally measured using the standard cylinder or cube. The measured strength is used for design. The accuracy of concrete strength is frequently challenged, particularly in large concrete structures where size effect of the test specimens is attributed for the differences. Many nondestructive tests were developed to evaluate concrete strengths. In recent years, it was obvious that these tests are unreliable. As the infrastructure decays, more nondestructive tests are required to evaluate the existing structures.

The Break Off Test is a recently developed nondestructive test. Although substantial amount of experimental investigations have been carried out on this …

Acuta Enews October 1994, Vol. 23, No. 10

ACUTA Newsletters

In This Issue

Special Emphasis Toll Fraud

Board Report

President's Message

ACUTA President

On the Campus of...

DC at a glance

Fall 1994, Wmpg 90.9 Fm

WMPG Program Guides

WMPG program guide for Fall 1994

Includes notes from Program Director, information on shows and events, and schedule.

October 1994, Wmpg 90.9 Fm

WMPG Program Guides

WMPG program guide for October 1994

Includes notes from Program Director, information on shows and events, and schedule.

Numerical Design Of Advanced Multi-Element Airfoils, Donovan L. Mathias, Russell M. Cummings

Aerospace Engineering

The current study extends the application of computational fluid dynamics to three-dimensional high-lift systems. Structured, overset grids are used in conjunction with an incompressible Navier-Stokes flow solver to investigate flow over a two-element high-lift configuration. The computations were run in a fully turbulent mode using the one-equation Baldwin-Barth turbulence model. The geometry consisted of an unswept wing which spanned a wind tunnel test section. Flows over full and half-span Fowler flap configurations were computed. Grid resolution issues were investigated in two-dimensional studies of the flapped airfoil. Results of the full-span flap wing agreed well with experimental data and verified the …

Ole Miss Engineer 1994

Ole Miss Engineer

No abstract provided.

Santa Clara Magazine, Volume 36 Number 4, Fall 1994, Santa Clara University

Santa Clara Magazine

6 - THE MIND THIEF November is national Alzheimer's Disease Month, drawing attention to an illness that robs patients of their memories, their competence, sometimes their very personalities. By Maureen McInaney '85

12 - CREDIBILITY MAKES A DIFFERENCE A look at a key element of leadership: building trust. By James M. Kouzes and Barry Z. Posner

18 - PUTTING THE PIECES TOGETHER SCU's $125 million Challenge Campaign is transforming the University.

24 - NO PROBLEMO A racked-up knee, a forfeited football scholarship, an extra 50 pounds-no problemo. A work of short fiction. By Jan Maulhardt '90

28 - THE NUCLEAR …

Bulletin - Fall, 1994, Civil Aviation Medical Association

Browse all Civil Aviation Medical Association Newsletters

A sixteen page newsletter of the Civil Aviation Medical Association. The newsletter provided news about civil aviation medicine and information related to the organization.

Predicting The Future Fate Of Pcbs In Lake Hartwell, Alan W. Elzerman, Kevin J. Farley, Frank M. Dunnivant, Craig Cooper

Publications

No abstract provided.

The Professional Air Traffic Controllers Strike: A Retrospective Analysis, Steven E. Durnin

Master's Theses - Daytona Beach

The purpose of this study was to assess the opinions, beliefs, and perspectives of former air traffic controllers who were terminated from employment with the Federal Aviation Administration for participating in the Professional Air Traffic Controllers Organization (PATCO) strike of 1981. The study examines the perceptions of the former controllers to determine their feelings toward the justification for going on strike over 13 years ago. This is relevant in light of recent events including the lifting of the ban against rehiring PATCO controllers by the Clinton Administration.

The data collected for this study were obtained with an opinionnaire mailed via …

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 10, Number 8, October 1994, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

An eight page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

Low Cost Schottky Barrier Solar Cells Fabricated On Cdse And Sb2S3 Films Chemically Deposited With Silicotungstic Acid, O. Savadogo, K. C. Mandal

Faculty Publications

No abstract provided.

Minutes Friends Of Tractor Test Museum October 1994, Tractor Museum

Lester F. Larsen Tractor Museum: Planning and Development Documents

Building Lease Student Employees Ted Worral Collection

Automating Workflows For Service Provisioning: Integrating Ai And Database Technologies, Munindar P. Singh, Michael N. Huhns

Faculty Publications

Workflows are the structured activities that take place in information systems in typical business environments. These activities frequently involve several database systems, user interfaces, and application programs. Traditional database systems do not support workflows to any reasonable extent: usually human beings must intervene to ensure their proper execution. We have developed an architecture based on AI technology that automatically manages workflows. This architecture, which executes on top of a distributed computing environment, has been applied to automating service provisioning workflows; an implementation that operates on one such workflow has been developed. This work advances the Carnot Project’s goal of developing …