Engineering Commons^™

Behavior Of High Strength Concrete And Slender Reinforced Concrete Columns With And Without Steel Fibers, Lin Showmay Hsu

Dissertations

A series of compression tests are conducted on 3 in. by 6 in. cylindrical specimens using a modified testing method that give the complete stress-strain behavior for both plain and fibrous high strength concretes with or without tie confinements. The volume fractions of fiber in the concrete are 0%, 0.5%, 0.75%, and 1.0%, respectively. Empirical equations are proposed herein to represent the complete stress-strain relationships of high strength and high strength fibrous concretes with compressive strength exceeding 10,000 psi. Various parameters are studied and their relationships are experimentally determined. The comparison between the experimental and analytical results shows to have …

The Influence Of Pore Fluids On Shear Strength And Stress-Strain Behavior Of Granular Soils, Prasanna Ratnaweera

Dissertations

When a dry granular soil is subjected to an external load, the stresses are transferred through mineral to mineral contacts. The shear strength of such a soil is governed by its contact properties. Presence of a thin layer of fluid between mineral to mineral contacts in a saturated soil will alter its contact properties. Therefore any change in the physical properties of pore fluid can logically be reasoned to influence the deformation characteristics of granular soils.

To investigate the influence of pore fluid viscosity on shear strength and stress-strain behavior of a soil, a series of consolidated drained triaxial tests …

The Durability Of Hot Mix Asphalt With Petroleum Contaminated Soils, Bonnie H. Dubose

Theses

Petroleum contaminated soils are considered solid waste They must be taken to solid waste facilities such as landfills or some other method must be found to deal with them. Landfills are becoming limited and is looked upon by the government as the least attractive option. One method that looks promising is to use petroleum contaminated soils in Hot Mix Asphalt Concrete.

In the research program the following are examined: 1) Investigation of material properties of the petroleum contaminated soil and aggregates 2) The proper procedure to produce a design blend of asphalt concrete. 3) Establishing the test procedure protocol to …

The Collapse Of The Cypress Viaduct During The Loma Prieta Earthquake Of October 17, 1989, Mohamed M. Eid

Theses

The Loma Prieta earthquake of October 17, 1989 in California was one of the most disastrous earthquakes in U.S history. It caused damage to commercial, residential, and industrial structures, transportation and utilities.

This study includes investigations about the Cypress Viaduct collapse re?ported by:

1. California Governor's Board of Inquiry [4].
2. National Institute of Standards and Technology (NEL) W.
3. 3The Author.

Investigators in the first report concluded that the collapse was due to horizontal ground motion. In the second one, it was due to the vertical ground motion.

In the author's investigation, a detailed static and dynamic analyses are performed to determine …

Catalytic Ozone/Ultraviolet Light Oxidation Of Organics In Water : Integrated Charcoal/Ozonation/Uv Radiation, Dawei Wang

Theses

A novel heterogeneous catalytic-oxidation technology where activated carbon is used as a catalyst-adsorbent, ozone serves as the oxidant and UV light as activation agent, is developed in a lab scale study. We demonstrate this process for destruction of recalcitrant organics in water i.e: combined oxidation by ozone, UV light plus activated carbon. The investigation includes evalution of various operating conditions: ozone levels, activated carbon levels; time for complete destruction of the individual target pollutants, plus evalution of activity of the continuously recativated carbon surface in-situ. All experiments were performed at room temperature in a semi-batch reactor. Seven representative chemicals was …

Three-Dimensional Beam-Columns, Mohammad Hassan Shams

Theses

This thesis explores several special cases of three-dimensional beam-columns and suggests that the method of finite differences can be used when a solution of general case is required. The thesis begins with a review of the three-dimensional beam-column equations and then shows how these equations can be used to generate the member stiffness matrix for the nonlinear analysis of three-dimensional frames. Examples are included which discuss the differences between the analytical and numerical solutions.

Planning Of Optimal Transit System Design, Yongning Liu

Theses

This study presents a methodological approach for finding an optimal design of bus transit service in an urban transportation corridor with elastic demand and under various objective functions. Service design decision variables to be optimized include the route length, route density, headway, number of stops and stop spacing pattern. The objective functions that optimize the transit system design include: minimizing operator cost, maximizing profit, minimizing sum of operator and user costs and maximizing the users' net benefits.

The analysis uses an elastic demand function wherein the number of trips are sensitive to the quality of service provided and price charged …

A Modified Approach To Flood Prediction In Urban Watersheds, Joseph Ofungwu

Dissertations

The purpose of this dissertation was to develop a better method for dealing with the problems of flood prediction in Urban Watersheds. It has long been realized that urbanization activity such as increased imperviousness, drainage improvements, etc. increases runoff volumes. Therefore, traditional flood prediction methods using the Log Pearson III distribution underestimate flood frequencies when applied to urban watersheds without modification.

In attempt to compensate for the effects of urbanization on streamflow, previous workers usually employed regional analysis techniques involving a number of different watersheds at various degrees of urbanization. Results obtained by this approach leave room for improvement primarily …

Evaluation Of Homogeneity For Hazardous Waste Solidification By Video Imaging Technique, Yi-Min Gao

Theses

The field of chemical solidification has just begun to mature into an accepted environmental technology for hazardous waste disposal. From the engineering point of view, some key issues still dominate the feasibility and effectiveness of hazardous waste solidification process. "Mixing" is essentially regarded as the most critical element but unfortunately, no evidence has been proposed to prove the homogeneity of the large monolith produced by solidification in order that the effectiveness of the solidification process can be evaluated in satisfactorily short time. The Homogeneity Evaluation by Video Imaging System (HEVIS) proposed in this study is to solve this problem with …

Kinetic Measuremenmt Of Decomposition Of Aniline, 2,4-Dichlorophenol And 1,2,4-Trichlorophenol Using A Calorimetric Method, Ming-Chin Chang

Theses

Biological treatment techniques for detoxification of toxic organic compounds have been studied and applied for many years. There are many research and commercial applications proving that the biological method is more economic and efficient than the other treatment methods.

The traditional biomass measurements are time-consuming tasks. Researchers have intended to develop a simpler, faster, and also accurate method for determining the bioactivity. This study has tried to use the microcalorimetric method to monitor the energy productions from the degradation of aniline, 2,4-Dichlorophenol and 1,2,4-Trichlorobenzene. Thereafter, by utilizing the data obtained from the present study, it was possible to compute kinetic …

Disinfection Of Wastewater Using Ultraviolet Radiation, David L. Klemm

Theses

The disadvantages associated with the use of chlorine for disinfection, in conjunction with improvements in ultraviolet radiation disinfection technologies have led to the recent increased use of ultraviolet radiation to provide disinfection of effluents from wastewater treatment plants. The theory of ultraviolet radiation and the engineering design of the ultraviolet disinfection system are discussed in depth.

The operational history and records of two wastewater treatment plants that use ultraviolet radiation for disinfection were analyzed in an attempt to develop correlations on the factors that affect ultraviolet radiation disinfection efficiency and to investigate as to whether disinfection with ultraviolet radiation is …

The Study Of Activated Sludge Settleability Using The Solids-Flux Analysis, Churng-Cherng Lin

Theses

The activated sludge was cultivated in two pilot-scale activated sludge systems under three ratios of BOD to N, equal to 20:1, 70:1 and 300:1 in the influent wastewater. The aeration tank of the activated sludge system was constructed in two different configurations: one without compartments in the tank, the other consisting of six compartments. The activated sludge withdrawn from the last compartment of each system was tested in a one-liter graduate cylinder to measure its zone settling velocity. The solids-flux method was employed to analyze the sludge settling characteristic as a function of solids concentration. The results show that the …

Mathematic Models On Leaching Behavior Of Chemical Solidification And Stabilization Process For Heavy Metal Sludges, Sz-Hung Chen

Theses

Chemical Solidification and Stabilization of toxic metal-containing sludges is one of the most important problems for environmental protection. Although Chemical Solidification and Stabilization of hazardous wastes prior to disposal is increasing in importance, very little work has been done concerning the leaching mechanisms and kinetic models.

In this study, we apply Freundlich & Langmuir isotherms on Chemical Solidification and Stabilization process, and the theoretical results match with experimental data very well. In the same time, we develop a simple methematical kinetic model which relates leaching concentration of heavy metal to curing time. In this study kinetic model, what you need …