Engineering Commons^™

The Analysis Of An Axially Symmetric Submerged Membrane Shell, Walter Earl Wehmeyer

Masters Theses

"The general theory of large elastic deformations is applied to the problem of a liquid-filled, axisymmetric membrane which is supported on a rigid horizontal plane and subjected to a variable external pressure. The variable external pressure is caused by submerging the membrane to various depths. The variation of the hydrostatic pressure in the inflating medium as well as in the surrounding environment is considered. By assuming large meridional deformations the stress field and the deformed shapes of a submerged membrane made of a neo-Hookean material are obtained. The effect of the initial shape on the deformed configuration of the membrane …

A Study Of The Effect Of Drilled Holes On The Concentration Of Elastic Stresses Around A Notch, Glenn Michael Kmecz

Masters Theses

"Hole drilling as a method for improving the toughness of notch weakened tensile specimens is investigated by means of a photoelastic technique. Tests were performed on 20%, 40%, 60%, and 80% notch depth specimens machined from PSM-1 photoelastic material. The basic criteria for success was no increase in the elastic stress concentration factor. The photoelastic results were verified by a finite element stress analysis of the 60% notch depth specimens. Comparison of the experimental and numerical results provide conclusive proof that no increase in the elastic stress concentration factor occurs when proper positioning of the drilled holes is accomplished"--Abstract, page …

Effects Of Cold Working Under Pressure On Subsequent Yield, J. G. Hoeg, Robert L. Davis

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A method utilizing high pressure fluid environments is described whereby a three-dimensional subsequent yield surface was determined for 304 stainless steel cylindrical parent specimens of this material were prestrained in axial compression under fluid pressure and then small sub specimens were sectioned from these parent specimens. Finite element techniques were used to optimize the parent specimen size so that a zone of uniform axial stress woidd result during the prestraining. Longitudinal strains in this zone were monitored during the prestraining and the subspecimens were cut from this region in a manner that did not allow the machining to appreciably affect …

Comparative Study Of Lightweight And Normal Weight Concrete In Flexure, Mohammad Zareh

Dissertations and Theses

This investigation represents a comparative study of the flexural behavior of lightweight and normal weight concrete. Both theoretical and experimental moment-curvature characteristics of the tested specimens were used to study the flexural behavior.

A generalized computer program to determine the moment-curvature relationships of a singly reinforced rectangular concrete beam was developed.

For this limited study it was observed that lightweight concrete beams when compared to normal concrete beams achieve comparable moment capacity (about 92% of normal weight concrete) but exhibit higher deflections (about 40% more than normal weight concrete).

Free Vibrations Of Circular Cylindrical Shells, Sushil Kumar Sharma

Masters Theses

"In this report bending theory of shells is used to determine the natural frequencies and mode shapes of circular cylindrical shells. The governing eighth-order system of differential equations has been put in a form which is especially suitable for numerical integration and application of different sets of homogeneous boundary conditions. The Holzer method is used to solve the eigenvalue problem. During numerical integration of the differential equations, the exponentially growing solutions are suppressed whenever they become larger than previously selected values. Numerical results are obtained for various shell geometry parameters and for three different sets of homogeneous boundary conditions. These …

Normal Mode Method Applied To The Transient Longitudinal Vibrations Of A Finite Rod With Material Damping And Viscoelastic Dispersion, David Arthur Levene

Masters Theses

"Longitudinal vibrations of a finite rod with material damping and frequency dependent material properties are examined. The normal mode method is used to investigate the transient response of a rod which is free to move in the longitudinal direction and is subjected to a transient longitudinal loading condition at one end. The equations of motion are derived and solved using both the differential equations approach and the energy methods approach of the normal mode method. The effects of material damping and frequency dependent material properties are considered by formulating the stress-strain relation for the material such that the modulus of …

An Energy Solution For Vibration Characteristics Of Free Thin Cylinders, Dale Elmer Leanhardt

Masters Theses

"In this report the flexural vibrations of the walls of free, thin, circular cylinders are considered. Theoretical expressions are developed for the natural frequencies by extending the approximate energy method of Arnold and Warburton to the free-free case. Furthermore, the developed expressions are shown to apply, as special cases, to the fixed-fixed and simply-supported cylinders analyzed by Arnold and Warburton. The energy solution for free-free cylinders is checked both experimentally using a 3500 pound-force, 5 to 2000 hertz, vibration exciter and numerically using the well documented SABOR IV-DYNAL finite element program. While the derived energy method accounts for any prescribed …

Hydrostatic Extrusion Of Tubular Products, John Lester Roth

Masters Theses

"The production of quality tubular products by hydrostatic extrusion has been demonstrated to be a highly satisfactory method. The forming of tubes by the floating mandrel method has been accomplished on mild steel, aluminum alloy, and brass. This thesis describes the method, equipment design and operation, and the results obtained in the hydrostatic tube extrusion. A discussion on the advantages of the use of hydrostatic over conventional extrusion is included. The hydrostatic extrusion system designed for this study is described in detail"--Abstract, page ii.

An Investigation Of Stress In The Monowall Construction System Subjected To Racking Loads, Louis Alex Kuhlmann

Masters Theses

"Several methods of analysis were employed to investigate the stress conditions of concrete block built in the MONOWALL Construction System, when subjected to racking loads. MONOWALL is a technique of assembling blocks with adhesive rather than conventional portland cement mortar. The analyses used in this study included strain gages on full-scale walls, photoelastic models, and a mathematical solution. Each method of analysis is reported separately in detail and the results compared to each other"--Abstract, page ii.

Continuous Interfacial Polycondensation Of Nylon 6-10, Sumer Raj Hundia

Theses

Nylon 6-10 has been prepared by continuous interfacial polycondensation hexamethylenedlamine and sebacoyl chloride in a stirred system. The effect of monomer concentration and stirring on the intrinsic viscosity of the polyamide 6-10 solution in m-cresol was measured.

As stirring (RPM) and monomer increased the intrinsic and the polymer yield through a maximum. Diffusion coefficients (D_AB) for hexamethylenedlamine were for hexamethylenedlamine were and were used for the calculations of j_D factors and K/DAB ratios. A relationship and j_D factors was established by a correlation curve.

Australian Tractor Test Report No. 58 : Massey-Ferguson 165, G H. Vasey, W. T. Brown

Journal of the Department of Agriculture, Western Australia, Series 4

THE Massey-Ferguson 165 is a general purpose farm tractor. The test tractor gave 50 drawbar h.p. with 59 h.p. at the P.T.O. at rated engine speed it comes within Class 5 of the Australian Standard Classification of Wheeled Tractors for Agricultural Purposes, AS Dl 0-1967. It is equipped with 18.4 x 28 in. pneumatic tyres. It has a threespeed gear box with a ratio change giving 6 forward and reverse speeds.

A Study Of The Effects Of Pressure-Induced Viscosity Changes On The Fluid Flow Characteristics In A Circular Tube, Robert Charles Weber

Masters Theses

"A method of determining the response of fluids under high pressure to quick-release into the atmosphere is presented in this report. The analytical efforts have been formulated into two parts, a closed-form solution and a numerical analysis. By assuming constant viscosity of the fluid a closed-form solution was obtained. The assumption of constant viscosity was found to be acceptable for the test fluids up to an initial pressure of approximately 10,000 psi. A numerical analysis became necessary for initial pressures over 10,000 psi, where the variable viscosity of the fluid had to be considered. The experimental work was conducted by …

The Design, Construction And Experimental Verification Of A Split Hopkinson Bar, Woosoon Bai

Masters Theses

"This thesis presents the design considerations for a dynamic loading device utilizing a projectile fired from a tube. Also included is a preliminary investigation of the stress-strain relation, under dynamic loading with the device, for a plaster known as Hydrostone. Design of the unit is based on the split Hopkinson pressure bar originally developed by Kolsky and on a similar unit in use at the Lawrence Radiation Laboratory, Livermore, California. The strain pulses along the pressure bars are sensed by resistance wire strain gages and displayed on an oscilloscope. The oscilloscope traces are photographed and manually digitized for insertion into …

Failure Of Lined And Unlined Small-Scale Cavities In Rock-Like Materials, Seung-Ki Yang

Masters Theses

"The strain conditions around statically loaded circular openings in rock-like materials and corresponding cavity-wall displacements were determined experimentally with resistance strain gages. The models were fabricated with lined and unlined openings simulating underground tunnels. Tests were performed with models of two different materials in plane stress and plane strain. Rock-like materials were designed and the strain gages were embedded at selected points within each model. The models often failed by tensile splitting through the opening early in the loading cycle causing the strains at certain points to deviate considerably from the theoretical values. Tangential strains on the vertical axis were …

Australian Tractor Test Report No. 55 : Nuffield 4/65, G H. Vasey, W. F. Baillie

Journal of the Department of Agriculture, Western Australia, Series 4

THE Nuffield 4/65 is a general purpose farm tractor of 49 drawbar horsepower.

With 54 h.p. at the P.T.O. at rated engine speed it comes within Class 5 of the Australian Standard Classification of Wheeled Tractors for Agricultural Purposes, AS D10-1967. I t is equipped with 18.4 x 30 pneumatic tyres.

It has a five speed gear box with a High and Low ratio change giving 10 forward and 2 reverse speeds.

Vibration Of An Internally Damped Tapered Truncated Cantilever Beam, Chimanbhai Magandas Patel

Masters Theses

"This thesis provides a vibration analysis of an internally damped, tapered, truncated, cantilever beam. Using two formulations of the problem based on: (1) Discrete mass and (2) continuous mass distribution, solutions are given for a beam having square cross section with linear depth and linear width variation. A Kelvin viscoelastic material for the beam is assumed. The vibration of the beam is considered to produce plane stress in the material, and the stress-strain relationship is applied only to the strain in the plane of bending. An exact solution for frequency of oscillation, mode shape, and steady state response is obtained …

Concrete In Dairies, D Roger Buchanan

Journal of the Department of Agriculture, Western Australia, Series 4

PRIME requirements for exposed concrete surfaces in dairies are that they should be easily cleansed and should not deteriorate in contact with milk and milk products.

In milking stalls, animal races and on loading platforms hardwearing surfaces which offer good foothold are also necessary.

Australian Tractor Test Report No. 49 : Mccormick International 624, G H. Vasey, W. F. Baillie

Journal of the Department of Agriculture, Western Australia, Series 4

AUSTRALIAN TRACTOR TEST REPORT

No. 49 - McCORMICK INTERNATIONAL 624

A Numerical (Matrix) Solution For The Vibration Frequencies And Modes Of A Nonuniform Rectangular Plate With Arbitrary Edge Conditions, F. David Utterback

Masters Theses

"The material presented in this thesis is designed to provide the practicing engineer with a practical, approximate method of solution for the increasingly important problem of plate vibrations. The technique presented herein is basically an application of the use of generalized coordinates to describe the elastic and inertial properties of a finite element representation of a nonuniform rectangular plate. The plate will be idealized by utilizing a modification of the grid work technique developed by Hrennifkoff as a lattice work of interconnecting beams. By employing the elastic displacements as generalized coordinates, the only required compatibility conditions are that the displacements …

Effects Of Pressure On The Mechanical Properties Of Magnesium, Joseph George Hoeg

Masters Theses

"The data collected in an attempt to evaluate the pressure dependency of the mechanical properties of extruded AZ31B-F magnesium alloy are presented herein. This information was compiled from the results of compression tests run in hydraulic fluid environments pressurized to 50,000 psi, and tension tests run in the atmosphere. Specimen axial load and longitudinal strain were recorded and converted to effective stress and effective strain parameters for presentation. The term pressure is defined, in this report, as the negative average of the principal stresses or, essentially, the negative of the hydrostatic component of stress. The effective stress and strain, at …

An Analysis Of Dirac Delta Generated Spherical Waves In An Infinite Maxwell Medium, William F. Breig

Masters Theses

"It is an accepted fact that the simple Maxwell and Voigt models do not usually represent the behavior of real materials. In order to make the results of a model more realistic, other combinations of springs and dashpots must be considered. To understand the more complicated models, it is desirable to have a knowledge of the Maxwell model since this element usually occurs either in series or in parallel in the advanced models. This investigation reports solutions of the spherical wave equation in both the elastic and viscoelastic media. Laplace transform techniques are used to obtain the parameters; stress, velocity, …

Noise In Cadmium Sulfide & Cadmium Selenide Photoconductive Cells, Edward Foster

Masters Theses & Specialist Projects

The primary object of this investigation is to design a system, including equipment and procedures, that can be used to evaluate the noise characteristics of photoconductive cells. The data once collected must be in a comprehensive and useful form. The secondary object is to use this system to evaluate a large number of cells of various types and to compare their noise profiles in a manner such that definite conclusions can be drawn concerning the absolute noise levels and profiles generated by the various cell types and the relations that may exist between the cells' noise output and the way …

Collision And Pursuit Course Terminal Closures For Spacecraft To Satellite Rendezvous, John Anthony Campbell

Masters Theses

"Collision and pursuit course closure maneuvers were studied for correcting position and velocity errors in the terminal phase of spacecraft to satellite rendezvous.

Minimum values of the ratio of initial range to velocity necessary to achieve rendezvous were determined for collision closures as a function of the initial line of sight. The time and velocity increment required for rendezvous were computed as a function of initial conditions.

Pursuit closure maneuvers were analyzed and time and velocity increments defined as a function of initial range, closing velocity, line of sight angle and angular velocity.

The velocity increments required were significantly higher …

Controlled Environment Broiler Houses In Western Australia, D F. Hessels

Journal of the Department of Agriculture, Western Australia, Series 4

The three main features which contribute to the better returns from controlled environment broiler housing are higher density, better conversion and a reduction in labour.

The higher initial cost of housing and higher running costs are more than covered by these three advantages.

Plastic Deformation Of Thin Plates With A Spherical Indenter, Benjamin Jen-An Chang

Masters Theses

"A method of determining the stress distribution in a thin plate deformed with a spherical indenter is presented in this report. The analysis is formulated in cylindrical coordinates and utilizes the basic principles of plasticity (von Mises yield criteria, Luwig stress-strain equation, Hencky Deformation theory, etc.). The problem is solved through the utility of a displacement function that, by virtue of its definition, automatically assures that the condition of volume constancy is satisfied. The boundary conditions are selected on the basis of having average, or integrated, effects corresponding to the physical constraints of the problem. Numerical integration is introduced to …

Dynamic Response Of A Simply Supported Beam To An Accelerating Point Load, Joseph Victor Cusumano

Masters Theses

"An analysis based on linear theory is presented for determining the dynamic response of a simply supported beam on an elastic foundation acted upon by a moving time dependent point force with axial forces included. This thesis extends the present theory to include an analysis of a point force accelerating uniformly across the beam. In particular, it is shown that the customary resonance conditions which are prevalent for a point force moving with uniform velocity no longer exist for the case of a point force accelerating uniformly across the beam.

The basic problem and its solution are presented for a …

Stresses In A Thick Spherical Shell, David Wayne Moore

Masters Theses

"This thesis reports a method to evaluate the stresses in a segment of a thick spherical shell. In the numerical examples loads due to thermal expansion as the shell is constrained at the free edge and a dead load acting vertically downward were considered for a shell assumed pinned but free to rotate and for a shell assumed completely fixed at the edge. A concrete shell was specifically studied but the method would also apply to a shell of any homogeneous, isotropic material"--Abstract, page i.

A Plastic Stress Analysis Of Cylindrical Wafers Under Elastically Deformable Compression Plates, Robert L. Davis, J. W. Jackson

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This paper represents an analysis of the pressure distribution occurring in axially loaded cylindrical wafers with, and without, elastic radial constraints. The purpose of this report is to demonstrate the resulting stress patterns that occur in short compression specimens frequently used in determining material properties, and in the opposed-anvil, or Bridgman-type, high-pressure cells. The influence of radial constraints, material strain hardening, wafer diameter-to-height ratio, anvil or plate deflection, and the wafer-anvil interface friction on the resulting stress distributions have been examined. The integrated normal stress distribution across the specimen surface has been verified experimentally via numerous tests in which each …

Dynamic Response Of Plates Due To Moving Loads, Theodore F. Raske, Alois L. Schlack

Mechanical and Aerospace Engineering Faculty Research & Creative Works

An analysis based on linear theory is presented for determining the dynamic response and the conditions of resonance for a simply supported rectangular plate acted upon by two types of moving loads corresponding to: (1) a point force of variable magnitude oscillating about a fixed position on the plate, and (2) a point force of constant magnitude traveling in a circular orbit about a fixed position on the plate. In addition to the ordinary resonance as produced by a variable magnitude load concentrated at a fixed position on the plate, resonance of the plate may occur due to the changing …

A Photoelastic Study Of The Stresses In A Deep Beam Using Partial Mirrors For Isochromatic Fringe Sharpening And Fringe Multiplication, Edward M. Raney

Masters Theses

"This paper is a photoelastic investigation of the stresses in a deep beam using partial mirrors to obtain isocromatic fringe sharpening and fringe multiplication. This method may be of particular value in photoelastic work for obtaining full field fringe multiplication and fringe sharpening for models which exhibit low fringe orders.

The photoelastic model used in this investigation is a deep beam with a length to depth ratio of one. A uniform load is applied over the center one-half of the beam. The beam is supported by two uniform loads distributed over a length of one-quarter the span.

A first approximation …