Civil and Environmental Engineering Commons^™

Solidification/Stabilization Of Chromium Contaminated Soil Using Cement And Fly Ash, Arunkumar Sripathi

Theses

Chromium, when present in the soil, can cause serious health hazards. Toxicity depends upon the concentration in the soil. Chromium in soil has become a major problem in some sites and a method must be developed so that it can be treated or disposed of in a safe manner.

In this research experiments are conducted to check whether the chromium contaminated soil can be solidified and landfilled in a safe way. To have a control over the amount of chromium present in the soil, pure soil (free from chromium contamination) was used and chromium was added in different proportion.

Another …

Centrifugal Modeling Of Leaking Underground Storage Tanks, Kuo-Neng George Chang

Theses

There are between 2 to 3.5 million Underground Storage Tanks (UST) located through this nation. Most of these tanks store gasoline and fuel oil. Many tanks in fact are or will soon be leaking, thus making them one of the major sources of groundwater contamination in USA. The fate and transport of chemicals from the leaking USTs is estimated from mathematical models. A major difficulty in these modeling efforts has been a crucial lack of information concerning the constitutive relationships governing multiphase contaminant movement.

Centrifugal modeling is an alternative to mathematical modeling, which may give an insight to the problem …

A Pc Based Computer Model With A Postprocessor For The Movement Of Groundwater, Joseph Byra

Theses

Currently available computer programs that model groundwater flow are inherently limited in their capabilities, in one way or another. Additionally, many of these computer programs are relatively inaccessible to the general user because they operate off of mainframe computers and sophisticated plotters. As a result, a simple to use computer program called 2DFLOW has been modified so it can be run on a personal IBM compatible computer. It models steady-state fluid flow through saturated porous media. In addition, a postprocessor called 2DPLOT has been developed. The postprocessor generates the equipotential contours and the flux vectors that describe the physics of …

The Dewaterability Of Anaerobically-Digested Sludges, Hui-Ching Lee

Theses

Vacuum filtration is the most common method used for sludge dewatering. Filtering or dewatering was operated to reduce the moisture content of the sludge after anaerobic digestion treatment.

The main purpose of this study is to determine the effect of the operating conditions of anaerobic digestion system on specific resistance in sludge filtration. The anaerobic sludges used for the present study were produced from the conventional single stage system and the multiple-stage system. From the experimental results, presently obtained that it is possible to compare the advantage and disadvantage of the two different digestion systems.

In addition, the effectiveness of …

Temperature Scale-Up On Rotating Biological Contactor Nitrification System, Kuanchun Lee

Theses

The relationship between RBC scale-up factor (SUF) and wastewater temperature is successfully developed by using Dr. Wu's mathematical model as a basis and 114 sets of data from the operation of 8 full-scale and 5 pilot-scale RBC plants served for NH3-N removal. The SUF obtained from this study is put into practice to present the scale-up of hydraulic loading for basic full-scale RBC plant design when the pilot study results are known and the design efficiency is fixed. An additional study is made to investigate two different RBC products manufactured by Autotrol Inc. and Lyco Inc. in terms of the …

A Critical Analysis On Cogeneration Policy, R. Tjahjokartiko Gondokusumo

Theses

It could be difficult to understand electricity problems without knowing its history; how a combine of legal, administration, and financial means effects electricity in the development. The recent public law on energy-related issues traceable by this study is the Renewable Energy and Energy Efficiency Technology Competitiveness Act of 1989.

In short, cogeneration was proposed to utility (as public property) from industry (as private property) under PURPA (of which National Energy Act is the legislative history). Thus, it should be clear that the problems of cogeneration is not pro or contra issues. It is a national issue. Then, a cogeneration planner …

Construction Cost Estimating In Project Management, Kalpit N. Patel

Theses

The primary objective of Cost Estimating is to support the timely generation of bid or alternative estimates. Cost Estimating also supports management analysis of estimate accuracy, reasonableness and project risk through the generation of summary reports and analysis. Estimates also provide a base of information during construction for such items as scope changes to the contract, variations in costs of the project cost, total project cost, feedback for scheduling etc.

Contruction cost estimating is the process of identifying and compiling the many items of cost that will enter into a construction project. This is a procedure that requires very detailed …

Experimental Evaluation Of Process Zone Deformation In Concrete, Cherng-Maou Meng

Theses

Concrete structures are often subjected to a variety of loading conditions. Under ultimate load design, concrete structures can resist these loads without evident deformation. However, under service, tension cracks will develop and depending on their location, they may impair load carrying capacity.

It is generally believed that microcrack development is preceeded by formation of a relatively long microcracked region. A large number of studies have indicated that due to formation of this process zone (microcracked zone), Linear Elastic Fracture Mechanics (LEFM) principles are not applicable to concrete. However, a number of nonlinear models can be developed if the length of …

Prestressed Concrete Columns Under Bending And Axial Load, Ajit Chiplunkar

Theses

A general analysis and design equation for slender and nonslender prestressed concrete columns subjected to uniaxial or biaxial moments combined with axial load is proposed. The proposed equation is an extension to the one developed by Hsu for reinforced concrete columns. The analytical results of the ultimate loads of eccentrically loaded slender prestressed columns are compared with the experimental results reported by Brown and Hall and Aroni respectively. The comparative study shows that the proposed equation of interaction diagram is in good agreement with the actual tests.

The ultimate loads of biaxially loaded short columns are also compared with the …

Shear Behavior Of Steel Fiber Reinforced Concrete Beams Under Monotonic And Cyclic Loads, June Suh

Theses

Up to now relatively few tests have been reported on shear behavior in fiber reinforced concrete beams. Even less experiments have been carried out under fatigue loading. In the present experiment, the reinforced concrete beams with 1 percent and 2 percent steel fiber volume fraction are investigated. Conventional stirrups are included in number of beams at certain intervals. Beams are loaded under monotonic and cyclic loads. The strength of beams are determined and the behavior of beams under each loading are observed in order to determine some advantages of adding steel fibers to reinforced concrete beams.

It has been found …

Study Of Essential Factors Affecting The Efficiency Of Sludge Digestion, I-Chang Tsao

Theses

The sludge produced by wastewater treatment plant has some major characteristics such as high COD ( 52093 mg/1 - 79683 mg/1) and VS ( 19247 mg/1 - 44178 mg/1). The present laboratory investigation has indicated that successful treatment and purification of the subject of sludge is possible using multiple-stage anaerobic digestion system.

The multiple-stage system is capable of degrading 40-55% of COD and 50 to 60% of VS. The conventional digestion system degrades 30-45% of COD and 40-50% of VS. After treated by conventional system and multiple-stage system, the concentration of COD and VS are still high (21200 mg/1 - …

Effects Of Fly Ash And Kiln Dust On The Compressive Strength Of Cement Mortar, Yitao Yu

Theses

Fly ash generated from coal-burning power plants has been an increasing problem to the utility company in terms of storage and disposal in compliance with the environmental regulations. Presently, fly ash has been widely used in the concrete mix. Research shows that fly ash can improve many properties of fresh and harden concrete. Landfill is another significant usage of fly ash. Usually, fly ash is stored in dry and weathered conditions. The properties of fly ashes from different sources and in different storage conditions are different.

In this research, the compressive strength of mortar containing cement replacement of Deep Hollow, …

A Study Of Methane Gas Production On Anaerobic Digestion System, Seng-Fung Su

Theses

The anaerobic sludge digestion process is not a recent development. At least 100 years ago in France,Louis H. Mouras designed and constructed fermenters to liquefy the sludge obtained from domestic wastes.

Since the turn of the century, the anaerobic fermentation process has been used extensively in the treatment of waste-water solids.

The necessity of preventing pollution of water resource, as a consequence of the rapid increase in human waste, demands adequate treatment of liquid wastes from domestic and industrial sources. For this purpose, the anaerobic digestion process can play an important role as a method for stabilizing and eliminating wastes …

Demulsification And Separation Of Oil In A Water/Particulate System, Fong-Jung Tai

Theses

The wastewater generated from installation factories contains high suspended solids ( SS ) and oil. Effective removal of oil and clay particles in washrack wastewater can be achieved by using organic polymer TFL-398 alone or in conjunction with alum. The dissolved/emulsified oil concentration and suspended solids are used to represent the degree of oil demulsification and clay particles destabilization, respectively.

To improve the efficiency of oil demulsification and reduce the chemical consumption, pretreatment of the influent wastewater is essentially necessary. pH adjustment to 11-12 generally reduces chemical requirement. Total oil concentration was reduced significantly at pH = 11.7 without any …

Calcium Bentonite In Containment Structures, Ramnarayan K. Tirumala

Theses

Experiments were conducted on calcium bentonite from different sources to determine its suitability as a material for slurry wall. The emphasis was placed on cement-bentonite types of materials. A few tests were conducted on specimens consisting of soil-bentonite materials. Permeability, swelling potential, and immersion tests were conducted. Specimens were initially permeated with water to determine which variety of bentonite was most suitable and later with chemicals. In cement bentonite specimens, the effect of addition of blast furnace slag, fly ash, and sand were also studied. Addition of slag cement lowered the permeability value by an order of magnitude, and with …

Behavior Of Slender High Strength Reinforced Columns Under Biaxially Eccentric Loading, Pei-Shiun Wu

Theses

The advantage of using high strength concrete is to reduce column sizes and to increase stiffness. At present there are not any available design aids and the code provisions that provide adequate guidelines for the design of slender columns in high strength concrete.

A total of four 3 in. by 3 in. dimension, 4 ft. length high strength concrete specimens were casted, cured and tested till failures in a vertical pinned-ended configuration.The experimental results were compared with the analysis using Hsu failure surface equation.

Moment, curvature and load deflection cures were obtained successfully from the present experimental tests. These curves …

Behavior Of Slender High Strength Steel Fiber Reinforced Concrete Columns Under Combined Biaxial Bending And Axial Compression, Tzuoh-Jaw Wu

Theses

A total of four slender high strength steel fiber ( 20 vol. hooked ends 1 in and 2 in ) reinforced concrete columns were casted, cured and tested to failure under biaxially eccentric load us—KT MTS testing system. The experimental load-deflection behavior exhibits not only the ascending branch but also the descending branch of the load and deformation curves.

The experimental ultimate load capacity was analyzed by the equation of Failure Surface Method developed by Hsu. recently, the result shows that the analysis method is able to predict the ultimate load value for biaxially loaded slender concrete columns.

For biaxially …

Investigation Of Mixed-Made Fracture In Concrete, Stylianos C. Aniftos

Theses

This study is aimed at evaluating the failure characteristics of concrete in the notched beam configuration. In general, for Mode I failure tension is commonly encountered. However, in the area of high shear stress, it remains to be a question whether shear or Mode II failure exists. Researches carried out in the past decade confirmed the existance of both Mode I and Mode II failure. It is the objective of this investigation to clarify this failure characteristics using FRANC an interactive fracture mechanics software.

The investigation carried out in this study used the experimental results of Bazant and Pfeiffer (3) …

Effect Of Inorganic Salts On Adsorption Process, Pai-Yuan Horng

Dissertations

`Small amounts (0.0 M-0.01 M) of inorganic salts (sodium chloride, calcium chloride, and aluminum chloride) added to bituminous coal fly ash and granular activated carbon in batch adsorption treatment experiments indicates the possibility of enhancing the extent and rate of adsorption process.

Experiments were conducted on aqueous solutions of highly toxic and hazardous chemicals, those include : phenol, benzene, toluene, isopropyl alcohol, and methyl-isobutyl ketone. Single and multiple solute systems were examined separately. Removal of organic pollutants was measured using a Flame Ionization Detector Gas Chromatograph.

This study investigated the role of inorganic salts during the sorption process. The results …

Testing And Modelling Of The Cleaner Wick System For In-Situ Treatment Of Contaminated Groundwater Plumes, Sanjiv I. Shah

Theses

The cleaner wick system, a modification of wick drains; a technology in recent use to consolidate low permeability soils, is proposed to treat contaminated groundwater plumes. Laboratory experiments on surrogate contaminants produce satisfactory results. Theoretical models are developed utilizing the cleaner wick system to treat volatile organic contaminants by air stripping and adsorption on granular activated carbon.

Treatment Of Trucking Station Wastewater By Two-Phase Anaerobic Digestion System And Rotating Biological Contactor, Tzu-Wen Uen

Theses

The wastewater produced as a result of trucking station activities has some major characteristics such as high COD (26,880 mg/1-42,925 mg/1) and BOD (12,278 mg/1-7,265 mg/1), high COD to BOD ratio (3.49-3.69), high pH range (3.72-11.7), and high grease content (480 mg/1-1,960 mg/1). Therefore, prior to any treatment, it is important to provide some sort of pre-treatment for pH adjustment and grease/oil removal.

The present laboratory investigation has indicated that successful treatment and purification of the subject wastewater is possible using two-phase anaerobic digestion system followed by rotating biological contactor. More than 90% of both COD and BOD was removed …

Application Research On Wastewater Reuse For Petrochemical Refining Industry In Taiwan, Lih-Shyan Lee

Theses

Nowadays water conservation and pollution abatement are needed to provide increasingly higher levels of treatment for industrial wastewaters.

Reducing treatment costs give us the incentive to minimize the volume of Wastewater effluent. Also, the national goal of zero discharge of pollutants to the waterways by 1985 provided further incentive -to minimize the flow of wastewaters.

A successful treatment of the wastewater discharged from the secondary effluent of the petroleum refinery plant to economically acceptable conditions offers a challenge to our technology.

Through this research, it is concluded that the excellent effluent water qualities produced from filtration and granular activated carbon …

Desiccation And Permeability Of Backfill Materials In Soil-Bentonite Walls, Hemendra J. Moradia

Theses

Soil-Bentonite Walls offer a cost effective solution to many groundwater problems in new and remedial work projects such as hydraulic barriers in dams, dewatering large soil cuts, and as part of pollution control systems around hazardous waste landfills. However, the performance of soil-bentonite walls in environments other then fresh water types is still a matter of great controversy. In recent years, some data on soil-bentonite backfill have became available. The data indicate change in properties of these walls with time of exposure and concentration of chemicals found in leachates. However, no research work is available in the literature on the …

Equation Of Interaction Diagrams For Prestressed Concrete Columns, Angamuthu Palaniappan

Theses

A general analysis and design equation for prestressed concrete column is proposed. This equation represents the strength interaction diagrams of prestressed concrete columns under bending about one axis and combined with axial load. The equation proposed is a modification of the one developed by Dr. Hsu, C.T. Thomas for reinforced concrete columns published in the ACI structural journal in 1988. The analytical results were compared with the results of tests on 30 eccentrically loaded prestressed columns reported by H.R. Brown and A.S. Hall. The results were in good agreement with the static analysis and the above mentioned test reports. The …

Experimental Study Of Rectangular And Square Concrete Member Under Combined Biaxial Bending And Tension, Ming-Hua Shiau

Theses

The proposed research is based on an equation developed by Dr. Hsu, which represents the strength interaction diagrams and failure surface for reinforced concrete rectangular and square columns under combined biaxial bending and axial load. In this research, two rectangular columns and two square columns subject to biaxial bending and tension were tested and compared with the proposed failure surface equation. This study shows that the experimental test results achieve more strengths then those calculated by the equation of failure surface.

Bond And Fatigue Characteristics Of High-Strength Cement-Based Composites, Somboon Chimaphant

Dissertations

The results of a series of tests on a variety of high strength cementitious composites yield a model from which an empirical equation of general normalized pull-out stress vs. pull-out displacement relationship is developed. A new variable named the "Brittleness Index" is defined and used in the proposed equation. Additionally, the concept of maximum strain is used to predict the fatigue life of high strength concrete.

Three sizes of deformed bars and two types of steel fibers with four different volume fractions were used to observe bond-slip and pull-out characteristics of high strength concrete. The results indicate that the maximum …

Anaerobic Biodegradation Of Trichloroethylene With The Addition Of Sugar Using Activated Carbon-Fluidized Beds, Suxan Huang

Dissertations

Anaerobic biodegradation of trichloroethylene (TCE) was carried out in a two-stage granular activated carbon fluidized bed bioreactor. The intermediate products were identified as: dichloroethylene (DCE), vinyl chloride (VC), 1,2-dichloroethane (DCA) and chloroethane (CA). Of the three geometric isomers of DCE, the trans-1,2 dichloroethylene (TDCE) was found to be the most predominant species, The production of DCA suggested a diverted reaction sequence from the conventional sequential reductive dechlorination pathway postulated in the past literature. CA was believed to be a product of VC and/or DCA. The co-substrate glucose was implicated for this reaction specificity. Based on our data and on other's …

Air Stripping Of Volatile Organic Contaminants Using Rotating Disc Contactor, Kai-Ping Hsueh

Dissertations

Previous studies have suggested that the transfer of VOCs to the atmosphere by air stripping may be a convenient and potentially cost-effective method to remove these compounds from the water. A Rotating Disk Contactor (RDC), similarly to other aeration devices, can provide intimate contact between the VOC-bearing water and air. It is believed that under carefully selected operating conditions, the RDC system are more competitive with packed tower than other aeration methods. The objectives of this study were to evaluate the feasibility of using the RDC to strip VOCs from the contaminated water and to develop a mathematical model to …

Permeability And Volume Change Characeristics Of Bentonite-Sand Mixes In A Contaminant Environment, Yuan-Hsun Wu

Dissertations

This research was conducted to study the characteristics of permeability and volume change of bentonite-sand mixes due to contaminants. The soil specimens consisted of clean sand, bentonite, and fly ash. Test liquids included seven diluted organic and inorganic chemicals and a landfill leachate.

Index tests included liquid limit, expansion, cracking, and sedimentation tests. Expansion tests proved to be the most useful for permeability evaluation in a contaminant environment.

The conventional consolidometer permeameter and flexible wall permeameter proved to be not completely satisfactory for testing soft bentonite mixes. A triple ring permeameter was developed to compensate for the limitations of these …

Competitive Bidding Strategy In The Construction Industry : A Game Theoretic Approach, Hongbin Chen

Theses

A game theoretic approach is applied to analyze competitive bidding in the construction industry because previous models do not consider the conflict of interest that exists among competitors. The game theoretic model improves corporate performance when compared to previous Bayesian analyses.

The game theoretic model is discussed in conjunction with construction contracting practice. Competitive bidding is formulated as a game theoretic model in which a contractor optimizes his bid price to maximize his utility or corporate performance. Using available historical data, order statistics are employed to access the distribution of estimated costs among bidders for a project. The winner's curse …