Engineering Commons^™

Numerical Inversion Of The Laplace Transformation And The Solution Of The Viscoelastic Wave Equations, Abbas Ali Daneshy

Doctoral Dissertations

"In the numerical inversion of Laplace transform two general techniques of inversion are analyzed; a study of the procedures based on an expansion of f̄(s) by a polynomial in 1/s (Salzer's method) provides accurate results for certain ranges of t. A curvature criterion for the selection of the range of points for polynomial interpolation, and a geometric distribution in this interval markedly improves the range and the degree of accuracy of inversion. The results may be further improved by multiplying f̄(s) by 1/s of 1/s². Other procedures are based on approximation of f̄(t). This investigation includes a general review of …

Spacing Of Explosive Charges, Calvin J. Konya

Masters Theses

"It is generally believed that the spacing of simultaneously initiated collar primed multiple charges is not dependent on the charge length. The stresses generated by explosive charges have been assumed to propagate through a material in a cylindrical manner. this assumption implied that the stress generated in any plane along the charge diameter would have been uniform in magnitude and direction. A finite explosive velocity along with a conical stress wave causes the stresses near the collar to differ from those farther down the column. for this reason, the spacing of charges would be dependent on charge length. An experimental …

Computer Simulation Of Scraper-Pusher Behavior During Early Open Pit Mining Operations, Martin Alan Thieme

Masters Theses

"A method has been developed for study and evaluation of overburden removal systems in open pit mining. The computer simulation method shows the effect of vehicle and course characteristics and the control of loading time on overall production and cost per unit of overburden removed. Data are available from vehicle manufacturers and from past mining experience. The data are punched onto processing cards and the system is then simulated and analyzed using a digital computer. The products of the system simulation consist of a tabulated listing of all control variables after each simulated vehicle loading and a system summary predicting …

An Investigation Of The Creep Characteristics Of Portland Cement Mortar Under Static And Dynamic Strain, Ikram-Ul-Haq Dar

Doctoral Dissertations

"The combined effect of static and dynamic loads on design of underground openings is currently receiving much attention. It is known that the time-dependent behavior of rock is considerably different when a dynamic load is superimposed on prestressed rock. The shape of an underground opening has a definite influence on the magnitude of the local stresses and these may be significantly larger than those due to the weight of the overlying rock alone. Under these conditions, even a small dynamic load in the form of vibrations caused by blasting, drilling and related operations may increase the stress beyond a critical …

A Comparison Of Friction And Drum Hoisting Systems On An Energy-Input Basis, Hemendra Nath Kalia

Masters Theses

"The purpose of this thesis is to provide a suitable basis for comparing the relative advantages of the friction and drum hoists under various conditions of operation.

Such comparisons are mainly and necessarily based upon physical characteristics of the mechanisms for lack of appropriate economic data. It is believed, however, that this inadequacy may be alleviated to some extent by substituting comparative theoretical energy requirements of' the two hoisting systems under identical duty conditions over a practical range of mining situations involving various depths and daily productions.

This has been accomplished by adapting a computer to standard mine-hoist design techniques …

Centrifugal Model Study And Finite Element Analysis Of Stress Near A Fault, Christopher Haycocks

Doctoral Dissertations

"The adverse effects of faults on the stability of underground openings has long been realized. To date, however, discontinuities and most other types of geologic heterogeneities have not been amenable to mathematical analysis using the classical theories of elasticity and plasticity. This investigation examines the stress distribution around a single discontinuity and compares the experimental and numerical methods used for the analysis. The theory of elasticity, employing the equations of compatibility, equilibrium etc., was used to determine a stress function for the stress distribution around a circular hole loaded in a centrifugal field. The analysis was terminated after the stress …

Ammonium Nitrate Blasting Agent (Anfo) For Land Clearing, G A. Greaves

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

The introduction of "prilled" AN has revolutionised explosives practice and made possible safer and cheaper methods of blasting.

This article outlines the methods of handling and using ANFO blasting agent for land clearing.

The Effect Of Moisture On The Compressive And Tensile Strength On A Variety Of Rock Materials, Richard A. Martin

Masters Theses

"The effect of moisture on the strength characteristics of rock materials has been neglected in the study of rock mechanics. This study was undertaken to determine if there was any effect on the compressive and the tensile strength of rock by varying the moisture content from an oven-dried to a saturated condition.
It was found, by testing eight different rock materials that the compressive strength per unit area decreased with an increasing moisture content. The tensile strengths per unit area, with the exception of the quartzite and the porphyry samples, also decreased with an increase in moisture content. The tensile …

The Development Of The Sonic Pulse Technique And Its Comparison With The Conventional Static Method For Determining The Elastic Moduli Of Rock, James Harold Deatherage

Masters Theses

"The determination of the elastic moduli of rock has long been a problem to the geophysicist, mining engineer and the civil engineer. There is a considerable amount of literature on determining Young's modulus by the sonic pulse technique. However, the use of this technique to determine the three elastic constants, Young's modulus, shear modulus, and Poisson's ratio from measurements of both the longitudinal and shear wave velocities presents some difficulties, especially in the method of accurately determining the shear wave velocities.

In this thesis, what is believed to be a new method of measuring shear wave velocities in the laboratory …

A Study Of Stress Distribution And Measurement Of Axial Strain Around A Pilot Hole During Overboring, Varakantham Sreedhar Reddy

Masters Theses

"Stress distribution around a pilot hole during overcoring was investigated. A study of axial strain on the borehole surface was undertaken. Two-dimensional epoxy resin models were prepared and stress frozen in a centrifuge. The stress-frozen models were examined under a direct-viewing polariscope. The magnitude of axial strain and the effect of strain relaxation on the pilot hole were measured on blocks of brittle materials. Factors contributing to discing of core during the overcoring operation were investigated and a mechanism of failure postulated. The loading conditions simulating in situ, core and bit pressures were applied individually to the brittle models and …

An Investigation Of Failure Patterns Of Layered Specimens Loaded In Uniaxial Compression, Narendra Y. B. Choudary

Masters Theses

"Uniaxial compressive strength for two and three-layered specimens was obtained with different thicknesses of layers and also for different length to diameter ratios. The fracture and failure pattern was studied. Shear and extension fractures were observed in the layers. Geometry and end conditions of the specimen had a great influence in the failure and fracture pattern.

The uniaxial compressive strength of a layered specimen was found to be lower than the weighted average strength and either low or high when compared to the arithmetic average strength, depending on the ratio of the heights of the layers. The compressive strength of …

A Theoretical Approach To The Problem Of Determining Ejecta Volumes In A Gravitational Vacuumed Half-Space, William J. Karwoski

Doctoral Dissertations

"The formation of an explosion crater is a highly complex process. All of the pertinent parameters governing the mechanisms of cratering are not clearly understood or known. Many cratering experiments were performed in desert alluvium in an effort to relate crater dimensions with charge weight and depth of burst. Various scaling laws were devised in an attempt to correlate the data gathered from these experiments. When cube-root scaling was used to correlate results of tests conducted at a constant scaled depth of burst, larger charge weights consistently gave smaller scaled results. This was particularly true of apparent crater volume. When …

An Introduction To Linear Time-Variant Digital Filtering Of Seismic Data, Richard Harold Lassley

Doctoral Dissertations

"The exploration geophysicist is constantly searching for new and better methods for analyzing seismic data. The primary purpose of this dissertation is to introduce linear time-variant digital filters as a technique for the filtering of seismic data. Methods of characterizing linear time-variant digital filters are discussed in general terms. The advantages of the different impulse and frequency responses are cited. In addition, the meanings and possible interpretations of the time and frequency variables introduced are considered. The concept of linear time-variant digital delay filters is presented along with their relationship to impulse responses. A pictorial diagram of discrete time-variant impulse …

The Cementing Of Hydraulically Placed Tailing Fill By The Oxidation Products Of Pyrrhotite, Stanley H. Alder

Masters Theses

"This thesis has been prepared to make available basic information on the use of the oxidation products of pyrrhotite to cement hydraulic tailing stope fill. As nothing has been published on this subject to date, a review has been made of pertinent information culled from accounts of work in related fields. From this study, a set of equations representing the most likely pyrrhotite oxidation reactions has been evolved and tests supporting these equations performed. Samples of fill, each containing from one to six percent of pyrrhotite, were cemented in the laboratory. They were then examined microscopically, subjected to unconfined compressive …

The Development Of Conical Stress Forms By Explosive Charges, Walter T. Casquino

Masters Theses

"Usually stresses generated by explosive charges during blasting are considered to propagate through materials in a spherical manner. Although conical stress waves had been suggested by a few investigators they have never been clearly defined or studied in the laboratory.

An experimental technique using models was developed to produce conical stress waves from an explosive. Several materials with different properties were selected as models for the purpose of determining whether or not conical waves could be generated in all materials.

This investigation showed that conical stress waves do exist under certain conditions, which would closely approximate those present for much …

A Study Of The Influence Of Shock Waves On The Stability Of Rock-Bolt Anchorage, Helmut W. Habenicht

Masters Theses

"An experimental method was developed to compare strain data for rock and rock bolts when exposed to shock waves released by blasting. During a 32-day period of experimentation, one rock sensor and four rock-bolt sensors were observed simultaneously. By their placement in the side wall of a structurally stable drift, secondary static stresses were excluded. Bolt gage responses, then, could be considered to originate only from a decay of anchorage stability during static conditions or as a reaction to the vibrations. Interpretation of test results indicated a distinct loss in bolt-strain during vibrations, accompanied by a smaller but steady loss …

Use Of Spent Sulphite Liquor For Stabilization Of Fractured Rock And Sealing Off Water Bearing Formations, Laxman Singh Sunda

Masters Theses

"The paper industry, in its process of manufacturing pulp from wood, produces large quantities of a substance called lignin, lignin sulphite, or lignosulphonate. This material has been disposed of as a waste product; however, it does have many potential uses. In this investigation, lignosulfonates were used as agents for bonding rock sections together and, as the chief component of gels, for filling the pores of artificial rock cores. The purposes of these tests were to find how this substance could be used in the mining industry, for stabilizing fractured ground around mine openings and for sealing off water influx into …

New Regulations For Explosives, Department Of Agriculture, Western Australia

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

THE Explosives Regulations, 1963, are now in operation and the new rules will affect purchase and keeping of explosives by small users.

A Study Of Plane And Spherical Compressional Waves In A Voigt Viscoelastic Medium, Gerald B. Rupert

Doctoral Dissertations

"In investigating the behavior of waves traveling through cohesive solids, two assumptions are usually made: that the propagating medium is either elastic or viscoelastic, and that the wave is either planar or spherical in form. For small distances from the source of the disturbance the medium can be considered elastic and the wave spherical rather than planar. The assumption of elasticity allows considerable simplification of the mathematical analysis, and assuming a spherical wave form is an acceptable approximation if the initial disturbance is essentially a point source and the propagating medium is nearly homogeneous. However, for large distances from the …

Ignition Time Lag: A Measure Of Explosive Energy Release, Paul H. Rydlund

Masters Theses

"By means of the resistance-element, or probe-wire, detonation-velocity measurement technique, explosive reactions from various blasting agents were studied. To reduce the number of variables, only standard AN-FO 94/6 mixtures were used, as are commonly employed today in constructions and mining operations. Accuracy of the data obtained was excellent, and the method proved itself not only relatively simple to operate but versatile in providing considerable information under many testing conditions. Studies of test records revealed the presence of a time-lag frequently occuring [sic] after primer detonation. Environmental factors such as confinement, charge diameter, primer size and energy content, and surface coatings …

A Laboratory Study Of The Effect Of Wettability Of Residual Oil Saturation In Artificial Cores., Socrates Nicholas Potamianos

Masters Theses

"In the past much emphasis has been placed on various studies of reservoir rock and fluid surface properties and their relation to the different oil recovery processes. Several laboratory methods (1, 2, 3) ^l/have been used by different investigators to obtain a more fundamental understanding of the many factors which have an influence on the oil recovery from reservoir rocks"--Introduction, p. 1

A Study Of The Phase Behavior Of Carbon Dioxide-Methane-Normal Decane Systems, Raja Audi Mansoor

Masters Theses

“The effect of carbon dioxide concentration, on solubility has been studied for several carbon dioxide-methane-n-decane systems. Experimental results were obtained using differential vaporization tests. Computational results were obtained using equilibrium constants.

The relation between solubility, bubble point pressure and solution carbon dioxide is presented. A ternary diagram showing the bubble point pressure behavior as a function of system composition is also presented”--Abstract, page ii.

The Characteristics Of Radial Strain Propagation Induced By Explosive Impact In Jefferson City Dolomite., Choon K. Quan

Masters Theses

"Blasting effects depend largely on peak radial strains propagated in rock media by explosive impact. To improve blasting design and control of secondary effects (e.g., structural fatigue), an equation for peak radial strain propagation induced by explosions was developed as follows: Emax = K e^-αr /r

An instrumental technique was designed to test the validity of the equation in the Jefferson City dolomite. Results showed ii that for 1-lb charges of 60% ammonia-gelatin explosive, peak strains, at any distance r, were reduced in amplitude in accordance with an exponential decay function of the type Emax = 281 e^{-0.026r …}

Investigations Of The Feasibility Of Transporting Ore In Open-Flumes., Kirtikant R. Sheth

Masters Theses

"Considerable effort has been expended and many data are published on developing the technologies of pipeline transportation and hydraulic hoisting. However, comparatively little information is available on the techniques of hydraulic mining, and nearly none ii is reported on conveying slurries in open flumes. For this reason, the author chose to investigate some of the parameters that influence open-flume transport.

It was found that Durand has assembled the findings of several investigators into a simple mathematical expression which is accepted as a standard for designing slurry pipelines. ·Further investigation by the writer revealed that Durand's formula, with only minor modification, …

Estimating Bench Design Parameters For Open-Cut Excavation, Rajni K. Gandhi

Masters Theses

"There are no direct relationships available that provide a basis for bench design of multiple-bench, open-cut earth excavations in competent materials when power shovels are employed. This study was undertaken to determine if mathematical design expressions could be developed when the production rate, material's properties, and equipment operating characteristics were known.

It was found that all bench dimensions were a function of the bench height, which in turn was controlled by the required rate of production. The investigation revealed that suitable relationships could be developed to guide in the control of bank stability, choice of shovel capacity, determination of the …

Application Of An Orifice Meter To Fan Testing., J. F. T. Agapito

Masters Theses

"In this investigation the application of an orifice meter to fan testing was studied and evaluated. An orifice meter was designed and was installed in a centrifugal fan duct. Measurements were checked and compared with those of a standard pitot-tube traverse and were found to be in very close agreement. It is suggested that a meter of this type could easily be adapted not only to laboratory work but also to field tests"--Abstract, p. ii

A Laboratory Model Study Of Fluid Cross Flow., James Gary Fore

Masters Theses

"A procedure for scaling and operating a laboratory model for the purpose of studying fluid crossflow between zones of different permeability is presented. A modified existing model is used to simulate conditions for three dimensional, incompressible, two-phase flow through a two-layer, unconsolidated, homogeneous porous medium.

Eight tests were made to show effects on crossflow between the zones. Qualitative results indicate crossflow from the high to the low permeability zone for various perforation ratios and mobility ratios"--Abstract, p. ii

Non-Ferrous Metal Mining And Smelting In Australia

School of Mines and Metallurgy Bulletins

Bulletin was published without an Abstract

Analysis Of Problems In The Performance Of A Natural Gas Storage Reservoir., Gerald Eugene Henderson

Masters Theses

"A digital computer technique is presented for predicting two parameters of underground natural gas storage reservoir performance: (1) the prediction of reservoir pressures and volumes, and (2) the prediction of optimum flow rate and pressure drawdown for a single well in accordance with the theory of water coning.

The outlined procedure for predicting gas storage reservoir pressures and volumes was not effective for the field studies, although certain conclusions have been drawn which should be beneficial in further studies.

The procedure for predicting optimum gas flow rate and pressure drawdown from a well without production of bottom water involved first …

Development Of A Technique For The Determination Of Capillary Pressure Curves Using A Constantly Accelerated Centrifuge, Robert N. Hoffman

Masters Theses

"A new technique for determining capillary pressure curves with a centrifuge has been developed and tested. Capillary pressure curves were determined for six cores by this technique and were compared to the curves for the same cores determined by the semi-permeable barrier technique. The technique differs from previously reported centrifuge techniques in that the centrifuge was slowly accelerated from zero to the maximum desired speed, rather than being held constant at particular, progressively higher speeds. An important advantage of this technique over other methods for determining capillary pressure curves is the short time required to obtain the desired amount of …