Materials Science and Engineering Commons^™

Concrete Cracking In Coastal Areas, S. R. Mpinzire

Tanzania Journal of Engineering and Technology (TJET)

The paper discusses cracking and corrosion of reinforced concrete (RC) structures in coastal zones where aggressive action of salt burdened air is the primary cause of concrete deterioration. Case studies are presented, along with discussion of possible remedies including local demolition, reconstruction and epoxy injection as well as concrete treatment.

Lateral Resistance Of Ring-Shank Nail Connections In Southern Pine Lumber, R D. Theilen, D A. Bender, David Pollock, S G. Winistorfer

Faculty Publications - Biomedical, Mechanical, and Civil Engineering

Ring-shank nails are used in engineered structures with lateral connection design values based on theoretically derived equations which were validated only for common nails. The goal of this study was to quantify the input parameters and lateral connection strength of several types of ring-shank nails in Southern Pine lumber and critically evaluate the applicability of the theoretical equations for ring-shank nails.

Two sizes of galvanized and ungalvanized, hardened steel ring-shank nails from two manufacturers were studied. The hardened, ring-shank nails carried significantly higher loads than the common wire nails studied. Because the current method of determining yield load does not …

Flexural Behavior Of Thermoplastic Beams With And Without Frp Reinforcement, Hilmi Coskun

Civil & Environmental Engineering Theses & Dissertations

This thesis presents the results of an experimental and theoretical study of the flexural behavior of thermoplastic beams with and without fiber-reinforced plastic (FRP) rebars. Tests are conducted on commercially available thermoplastic beams known as Seatimber. The normal stress-strain relations of both the thermoplastic material and FRP rebars are obtained in tension and compression experimentally. These mechanical property curves are then used as part of the input for developing the theoretical moment-curvature relations using an iterative equilibrium procedure. The moment-curvature relations are in turn used for predicting the beam load-deflection curves via the central finite-difference procedure. Behavior predictions are made …

Withdrawal Strength Of Ring-Shank Nails Embedded In Southern Pine Lumber, M J. Skulteti, D A. Bender, S G. Winistorfer, David Pollock

Faculty Publications - Biomedical, Mechanical, and Civil Engineering

Ring-shank nails are used extensively in post-frame construction due to their superior performance, yet surprisingly little testing has been done on nail sizes above 12d. Experience in the post-frame industry suggests that published allowable design values for ring-shank nails may be overly conservative and need revision. The goal of the research reported herein was to characterize the withdrawal strength of ring-shank nails embedded in Southern Pine lumber. Three sizes ofgalvanized and ungalvanized (bright) ring-shank nails from two manufacturers were studied. Ring-shank nails had approximately twice the withdrawal resistance of smooth-shank nails of the same diameter. Galvanizing slightly reduced withdrawal strength …

Threaded-Nail Fasteners - Research And Standardization Needs, B L. Wills, S G. Winistorfer, D A. Bender, David Pollock

Faculty Publications - Biomedical, Mechanical, and Civil Engineering

Threaded nail fasteners are commonly used in agricultural and commercial post-frame structures, yet there has been insufficient research to fully understand the effect of threads on withdrawal and lateral load resistance. The objective of this article is to review technical information on threaded nail fasteners and to identify problems facing manufacturers, designers, and users of threaded nail fasteners for engineering applications. Recommendations are given concerning research and standardization needs.

Seismic Performance Of Confined Sill Plate Connections, Joseph M. Bracci, Rebecca F. Stromatt, David Pollock

Faculty Publications - Biomedical, Mechanical, and Civil Engineering

In the aftermath of the 1994 Northridge earthquake, extensive field investigations revealed damage in wood frame construction in the form of splitting of the 2 X 4 or 2 X 6 wood sill plates along the line of anchor bolts that typically connect shear walls to the masonry or concrete foundation. Due to the severity of such brittle failures, the city of Los Angeles has recently restricted the use of 2X dimension lumber in sill plates and requires the use of 3X dimension lumber. This paper presents an experimental investigation of the performance of 2X dimension lumber sill plate connections …

Lrfd For Engineered Wood Structures - Connection Behavioral Equations, Thomas E. Mclain, Lawrence A. Soltis, David Pollock, Thomas L. Wilkinson

Faculty Publications - Biomedical, Mechanical, and Civil Engineering

A new design specification for engineered wood structures has been proposed in load and resistance factor design (LRFD) format. This paper provides an overview of the proposed LRFD connections design criteria. The connections design provisions are, in part, calibrated from allowable stress design provisions. Major changes from historic practice, however, result from a change in behavioral equations to a theoretical base for predicting the lateral strength of connections using bolts, screws, and nails. New provisions for axial withdrawal of driven and turned fasteners, as well as combined axial and lateral loading criteria are also proposed. Safety levels were calibrated to …

An Experimental Study For The Effect Of Specimen Size On Shear Behavior Of Granular Materials, Clifton Linwood Parker Iv

Civil & Environmental Engineering Theses & Dissertations

An experimental study was undertaken to look into the effect of specimen size on the volumetric behavior of granular triaxial specimens. It was hypothesized that the specimen preparation mold creates a unique particle arrangement near the perimeter of the specimen and thus, for smaller specimen diameter relative to the particle size, it will exhibit a greater effect of the unique particle arrangement on the volumetric behavior. particles was used A single distribution of spherical glass throughout the testing. The tested specimens were 3.6, 2.8, 2.0, 1.4, 1.0, and 0.6 inches in diameter with a fixed two to one specimen height …

Materially Nonlinear Finite Element Analyses Of Trusses And Slab-On-Grade Problems, Moayyad Moh'd Al-Nasra

Civil & Environmental Engineering Theses & Dissertations

The overall approach is to employ the finite-element method along with specified material models to account for material nonlinearity. This study includes two different applications: truss structures and slabs-on-grade.

Procedures for materially nonlinear analysis of truss structures, which apply for both determinate and indeterminate cases are proposed. The proposed procedures are simple and can handle a variety of different stress-strain functions, and the applied load does not have to be incremental. Proposed procedures results are verified with the output of NASTRAN.

A finite-element model for slab-on-grade is introduced. The concrete slab is represented by eight-node brick elements, and the joints …

An Analysis Of Reinforced Concrete Composites Utilizing Recycled Polyethylene Terephthalate Thermoplastic, Jaroslav V. Vaverka

Dissertations and Theses @ UNI

Removing plastic from landfills does not solve the solid waste problem entirely. Plastic products are difficult to recycle because, unlike aluminum or glass, the plastics used in food packaging cannot be reused for the same purpose. Among the commonly used plastic resins, polyethylene terephthalate (PET) has been widely adopted by the packaging industry. This research study was concerned with recycling of PET thermoplastic in concrete as a way to reduce the volume of solid waste.

Current surveys of recycling efforts reveal that existing PET recycling approaches have become inadequate. Solid waste management is stressing the eminent need for new recycling …

Micromechanics Of Granular Materials And Its Relation To Wave Velocity, Tarun K. Agarwal

Civil & Environmental Engineering Theses & Dissertations

The macro characters of the granular materials depend upon micromechanical parameters such as the void ratio, particle shape, contact force distribution, and initial state of the fabric of the assembly. Since it is difficult to evaluate these internal parameters from laboratory experiments, a macro measure is desired which depends directly on these internal parameters. One such measure has been shown to be dynamic shear modulus but it was incomplete in predicting directional changes in the internal parameters. Therefore, it is hypothesized here that the complete elastic moduli matrix will have more direct information about the internal parameters, especially the dynamic …

Carrying Capacity And Cracking Resistance At The Support Zone Of Halving Joints In Reinforced Concrete Beams, H. W. Chung

Tanzania Journal of Engineering and Technology (TJET)

Abstract

Carrying Capacity And Cracking Resistance Of The Bracket, S. Mpinzire

Tanzania Journal of Engineering and Technology (TJET)

Abstract

Behavior Of Ductile Materials Under Impulsive Loading, M. Y. Brunner

Tanzania Journal of Engineering and Technology (TJET)

Ductile materials under dynamic loading are known to be able to absorb energy and thereby delay or even prevent structural failure. This paper is concerned with such behaviour in the case of impulsive loads of short duration. It is shown that even when the feared, unstable, labile condition is attained, failure may not necessarily occur. This behaviour is particularly impressive for structures with large mass, because it is essentially the mass which slows down the attainment of the failure strains. If the impulsive load dies away quickly enough, the constant plastic resistance will be adequate to bring the increasing deformations …

Effect Of Fabric On Stress-Strain Relation, Volume Change, And Dynamic Shear Modulus Of Ottawa Sand, Ming-Tarng Chen

Civil & Environmental Engineering Theses & Dissertations

To evaluate the effect of fabric on stress-strain behavior, volume change, and the dynamic shear modulus of Ottawa sand, four series of tests on hollow cylindrical specimens were performed by a torsional simple shear/resonant apparatus. All specimens were first isotropically consolidated, and then sheared along the different stress paths while keeping the mean effective stress constant. The test results showed that depositional fabric had a slight influence on the stress-strain behavior, and one half-cycle of pre-shearing created a clear anisotropy on the stress-strain response. The intermediate principal stress had a dominant effect on volume change characteristics but it might not …

An Analysis Of The Abaca Natural Fiber In Reinforcing Concrete Composites As A Construction Material In Developing Countries, Rolando V. Magdamo

Dissertations and Theses @ UNI

This study was undertaken to analyze the flexural and splitting tensile strengths and the ductility of abaca fiber-reinforced concrete composites. Abaca fibers are natural fibers of vegetable origin prepared from the abaca plant which is a native plant of the Philippine Islands. The purpose of the study was to investigate how various volume-fractions of the abaca fiber in the concrete mix could affect the mechanical properties of the concrete matrix.

A concrete design mix containing a volume ratio of 1.0 part Type I Portland...cernent and 3.0 parts sand was utilized in the preparation of laboratory test samples. Abaca fibers were …

Removing Fluoride From Drinking Water By Organic Polymers, Eleni Davou Achilleos

Civil & Environmental Engineering Theses & Dissertations

Fluoride is a substance that can provide beneficial or detrimental effects depending on the total amount ingested. Naturally occurring high fluoride concentrations exist in many drinking water supplies. The fluoride removal methods developed in the past have been found to be either impractical and/or not cost effective.

The purpose of this study was to determine whether organic polymers can effectively remove fluoride. The water used in this study contained naturally occurring fluoride concentrations between 4.5 to 5.5 mg/1 and it was collected from the City of Franklin, Virginia, water supply system. Laboratory jar test procedures, which simulated a conventional water …

Structural Members Comprised Of Composite Wood Material And Having Zones Of Diverse Density, Anders E. Lund, Gordan P. Krueger

Michigan Tech Patents

The disclosed invention includes an improved construction of structural members such as railroad crossties, highway spin posts and highway guard posts and to construction of said members from composite wood material including elongated wood flakes and to a method for making such improved structures.

The Effect Of Adhesive Bond Strength Of Selected Species Of Laminated Wood, Daniel L. Henderson

Graduate Research Papers

Wood laminating has been used by man for centuries and is a very important part of industrial enterprises today. In most woodworking textbooks reviewed however, those sections devoted to wood laminating are typically miniscule. Topics are hastily covered and only general information is provided. This study has been conducted in order to provide more adequate explanation of the laminating process in addition to those presently available and to explore the interrelationship of laminated components with the ultimate function of the product. A glance at any furniture manufacturing or construction industry periodical, however, will show the importance of wood laminating in …

Structural Design Of Built-Up Plywood Box Beams, Michael J. Sneddon

Graduate Research Papers

The purpose of this study, given the background mentioned above, is to investigate the structural design of built-up plywood box beams and to develop an instructional unit based on their design.

The scope shall be limited to statically determinate beams with either uniformly distributed loads or typical girder loadings.

The resulting instructional unit will be designed as an addition to a course in structural wood design at the vocational-technical/community college level.

Ua64/3 Readout, Wku Industrial Education & Technology

WKU Administration Documents

Newsletter includes articles:

• Construction Complete on Environemental Science & Technology Building
• Wendt, Donald. Some Reflections on teh Kentucky Industrial Education Association
• Tomazic, Norman. Technology Assessment A Step Toward a Humanized Technology
• Frank Pittman has Individualized Course Published
• Lowrey, H.J. Industrial Arts in a Changing Society
• H.B. Clark
• Growing Interest, re: Architectural Drafting
• Old Building Begins Renovation
• Walter Nalbach: Craftsman at Home

Direct Design Of A Portal Frame, Angel Fajardo Ugaz

Dissertations and Theses

This investigation was undertaken to develop plastic design aids to be used in the direct design of optimum frames. It uses the concept of minimum weight of plastically designed steel frames, and the concept of linear programming to obtain general solutions. Among the special characteristics of this study are: A. The integration of both gravity and combined loading conditions into one linear programming problem. B. The application of the revised simplex method to the dual of a parametric original problem. C. The application of A and B above in the development of design aids for the optimum design of symmetrical …

An Experimental Study Of Lateral Soil Pressures And Moments On Flexible Sheet Piles, James H. Donahue

Civil & Environmental Engineering Theses & Dissertations

In order to study the effect compaction has on lateral earth pressures exerted on and bending moments in steel sheet pile bulkheads, an experimental study was undertaken which employed the placement of a non-cohesive soil at two specific densities against three model piles of varying thicknesses. The soil was placed both in a loose and a dense state and the bending strains and deflections of the sheet piles were measured at various stages of backfill. Surface loadings were then placed after completion of the backfilling to observe the effects these loads had on the bending moments. The results of the …

Effects Of Oxygen Content Of Admitted Gases In Sulfide Flotation, Brian J. Boyle

Bachelors Theses and Reports, 1928 - 1970

No abstract provided.

Methods Of Studying The Effects Of Frothers, Frank L. Bazzanella

Bachelors Theses and Reports, 1928 - 1970

No abstract provided.

Non-Ferrous Metal Mining And Smelting In Australia

School of Mines and Metallurgy Bulletins

Bulletin was published without an Abstract

Studies In Modulation Of Interfacial Reactions For Certain Sulphide Minerals, Robert Owen Beyaert

Bachelors Theses and Reports, 1928 - 1970

No abstract provided.

Habit Modification Of Naclo3 With Nai, William A. Coghlan

Bachelors Theses and Reports, 1928 - 1970

No abstract provided.

Production Of Standard-Grade Ferromanganese In An Electric Arc Furnace, Force F. Baney Jr.

Bachelors Theses and Reports, 1928 - 1970

The investigations conducted in this project were essentially concerned with the effects of various compositions of two different slag systems upon the increased recovery of manganese in a standard-grade ferromanganese.

Investigation Of The Ternary System Silver-Aluminum-Indium (Ag-Al-In), Elvin H. Beardslee

Bachelors Theses and Reports, 1928 - 1970

This thesis paper contains material pertaining to & preliminary investigation of the ternary system Ag-Al-In. Procedures in this preliminary investigation are discussed in detail.