Civil Engineering Commons^™

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 …

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, …

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 …

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 …

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 …

Optimal Design Of Prestressed Concrete Members Using Numerical Techniques, Nasseruddin Syed

Theses

This research consists of the application of nonlinear optimization techniques for the economical design of prestressed concrete members. A computer program using Lattice and Matrix methods of optimization is employed for least weight design of I-shaped prestressed concrete girders. The program calculates the most optimum values of the cross-sectional dimensions.It has the freedom to impose any constraints on any of the design variables, including sectional dimensions, eccentricities, concrete cover and limiting stresses.

Comparison of results obtained in this thesis with other analytical methods indicate that with the advent of computers, the numerical methods have a definite advantage over other analytical …

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 …

Adsorption And Desorption Of Chromium On Clayey Soils, Ker-Shu Tan

Theses

Chromium residue waste was produced during sixties in the chromium production process. It was used as construction fill. Problems associated with chromium waste sites include structure distress and surface and groundwater contamination.

The purpose of this study was to investigate the adsorption and desorption of chromium on soil. In order to achieve this purpose, experiments were conducted to study the effect of pH, type of chromium compound, and type of soil on adsorption and desorption.

Experiments were performed on kaolinite, bentonite and sand. In our study, it was found that sand had almost no adsorption for chromium. Kaolinite had less …

Slurry Wall Backfill Integrity And Desiccation, Mahendraratnam Thilliyar

Theses

The upper reaches of slurry wall, in a waste containment structure may under go cycles of wetting and drying, because of seasonal ground water level fluctuations. This may result in desiccation and cracking of back fill material. Experiments were conducted to study these effects with water, aniline, phenol, hydrochloric acid solutions on soils containing different proportions of bentonite, kaolinite, and sand. The largest crack was formed with phenol and the smallest with water. With hydrochloric acid no crack was formed. With increase kaolinite content, the width and density of crack decreased. Hydraulic conductivity tests on cracked specimens indicated high hydraulic …

Thermal Desorption Of Phenol Contaminated Clay Soils, Chia-Ling Ting

Theses

Clay mineral/organic reactions have been studied extensively by a numerous physicochemical methods. There also has been extensive research done in the areas of adsorption, Lewis acid-base reactions, desorption, adduct formation. Many of these studies explain the role and dehydration of silicates.

Studies have shown through extraction, thermal analysis, and gas chromatography. That there is more than one type of bonding, weak and strong, taking place between the clay mineral and the organic waste.

In order to determine the practicality of the containment technology, this research has been investigated by using more powerful tools, such as thermogravimetric analysis, differential scanning calorimetry …

Sediment Transport/Sand Bypassing Analysis At Manasquan, Nj, Christopher Clemens Obropta

Theses

An experiment to determine the longshore sediment transport rate using a fluorescent dyed sand tracer was conducted during the summer of 1987 to help determine the feasibility of sand bypassing at the Manasquan Inlet in New Jersey. After the fluorescent sand tracer was introduced to the longshore transport system, the Spatial Integration Method was used to sample the surf zone. The Spatial Integration Method allowed the tracer cloud to be monitored in both time and space. The tracer experiment provided a constant to be used in the calculation of the longshore sediment transport rate. This constant is specific to the …

Laboratory Model Studies Of Pneumatic Fracturing Of Soils To Remove Volatile Organic Compounds, Panayiotis Papanicolaou

Theses

Bench-scale laboratory studies were conducted from January 1988 to October 1988 to demonstrate the feasibility of using Pneumatic Fracturing* to enhance the removal of Volatile Organic Compounds from the vadose soil zone. Experiments were conducted to investigate: 1) The effect of pneumatic fracturing on the rate of contaminant removal; and 2) the injection pressures required to initiate soil fracturing.

Contaminated soil was placed and compacted in three identical 15 inch square by 30 inch high plexiglass tanks. The first tank was equipped with a vapor extraction system consisting of vacuum and/or positive air injection. The second tank was equipped with …

Experimental Evaluation Of J-Integral For Fiber Reinforced Concrete Subjected To Impact Loading, Piyushkumar Patel

Theses

This research presents an experimental Evaluation of J-Integral for Fiber Reinforced Concrete Subjected to Impact Loading. Three-point edge notched bend specimen were employed in evaluation of J-Integral using both the multi-specimen, and the single specimen techniques. In the multi-specimen technique three different notch lengths were employed for extracting the energetic fracture parameter J_Ic. In the single specimen technique, the method developed by Rice[13] was used to evaluate J_Ic at three different notch lengths.

Different proportions of fiber were employed in determining the J_Ic values. Experimental results from present study indicates that the J_Ic values calculated …

Study Of Steel-Concrete Interface Behavior Of Reinforced Concrete Members, Jun Wan

Theses

The main objective of this thesis work is to study the steel-concrete interface behavior of reinforced concrete members using the nonlinear finite element method.

The reinforced concrete member was modeled as a continuum consisting of plane stress rectangular elements which represent the concrete, pin-joint two node bar elements which represent the reinforcing steel, and the nondimensional linkage elements which represent the bond stress-slip, aggregate interaction and dowel action effects. The load increment procedure is employed to carry out the nonlinear analysis.

An axially loaded tensile specimen, a deep beam specimen and a shallow beam specimen were analyzed. The results from …

Experimental Evaluation Of J-Integral For Concrete Subjected To Impact Loading, Naishan Zhang

Theses

This thesis presents an experimental evaluation of J-integral for concrete subjected to impact loading. Twenty four three-point bend specimens with two different thicknesses and mid-span notch lengths were tested under impact velocities of 167.22 in/sec (424.74 cm/sec) and 261.78 in/sec (664.92 cm/sec). Multi specimen method was used to analyze and estimate J_I and its critical J^-Ic values. Effects of specimen thickness and impact velocity on J^-Ic values were observed and discussed. Evaluation of J^-Ic Values from the experimental results of this study indicated that can be characterized as a material constant even under different impact velocities. …

Adsorption Of Organic Compounds By Microbial Biomass, Ariamalar Selvakumar

Dissertations

The adsorption of hazardous organic compounds such as phenol, 2-chlorophenol, 2-nitrophenol, chlorobenzene, and ethylbenzene onto two types of inactive microbial biomass (activated sludge and nitrifying bacteria) was studied. The adsorption isotherms could be expressed by the Freundlich adsorption isotherm and were found to be nearly linear over the range of concentrations (50 - 200 mg/1) studied. Desorption studies showed that the adsorption process was partially reversible. Heat of sorption was estimated and indicate that the biosorption process involves a physical rather than a chemical mechanism. The adsorptive capacity of biomass is about two to three orders of magnitude less than …

The Evaluation Of The Impact Of Reducing The Domestic Wastewater Phosphorus On The Algal-Related Water Quality Of The Hudson/Raritan Estuary And Northern New Jersey's Coastal Waters, Ron Gautreau

Theses

An investigation was undertaken to examine the planktonic algal-related water quality of the Hudson/Raritan Estuary and northern New Jersey's coastal waters with respect to quantifying the relationship between the amount of phosphorus loading to the planktonic algal-related water quality responses. Recreational and commercial uses of northern New Jersey's coastal waters have at times been impaired by excessive growth of planktonic algae. Using population equivalents and export coefficients the amount of domestic wastewater and land runoff derived phosphoruscontributed to the Estuary was estimated. The P load contributed to the Estuary via the discharge of New York and New Jersey domestic wastewater …

Unsaturated Column Studies Of Silty Sand Using A Conservative Tracer, Canagasabapathy Nallianathan

Theses

A laboratory study was conducted to investigate the flow and mass transport of a conservative tracer in the unsaturated phase. For this purpose, a relatively "large-scale" cylindrical column(12 in. O.D. x 4 feet long) was fabricated and equipped with tensiometer and psychrometer sensors.

The soil used in the study was a New Jersey based silty sand compacted to an average dry density of 93 lb/ft³. The soil was permeated with a 0.5 M NaCl solution infiltrated at the top of the column using a perforated spiral tube assembly. The permeant was applied at a constant rate of approximately …

Co-Metabolism Of Pentachlorophenol With Glucose Using Two-Stage Anaerobic Activated Carbon Fluidized Beds, Zen Wang

Theses

Abstract - Detoxification of pentachlorophenol by using a two-stage anaerobic biological activated carbon fluidized bed has been investigated. Glucose was introduced as a cosubstrate to determine the relationship between the glucose/PCP ratio and the extent of PCP detoxification in such a system. This system has been proved to be effective in the removal of both PCP and COD. Ratio of glucose to PCP predominates the performance of the system throughout the whole course of this experiment. At a glucose/PCP ratio of 0.33, the system has a highest reduction of both PCP and COD. Addition of glucose to the highly PCP …

Decontamination Of Contaminated Clay Soils By Thermal Treatment, Chandrakanthi Weerasinghe

Theses

An experimental investigation on the desorption of contaminated clay soils by thermal treatment was performed. This study was carried out on two clay soils (kaolinite and bentonite) sorbed with three liquid organic compounds (phenol, chlorophenol, and chlorobenzene). The study consists of two different phases, the adsorption and desorption. The results on batch equilibrium adsorption were correlated with different isotherm models of which the Freundlich isotherm model was found to be best fit in predicting adsorption capacities of kaolinite, and that for bentonite was found to be the linear isotherm model.

A thermal desorption study followed the equilibrium adsorption study. A …

Development Of A Rock Model Testing Capability At The New Jersey Institute Of Technology And Testing Of Plane Stress Models Possessing A Central Circular Opening With A Nearby Horizontal Discontinuity, David R. Good

Theses

This thesis had three main objectives. They were to develop a rock model testing capability at N.J.I.T. by (1) developing and building a load testing frame for rock models, including all necessary appurtenances and load measuring devices, (2) developing a rock modelling material and quantifying its properties, and (3) applying the capabilities described in items 1 and 2.

A high capacity load test frame was constructed from structural steel members. Heavy screw rams were utilized to apply load and specially constructed proving rings were employed to accurately measure load. Additionally, load platens and other support equipment were constructed.

The model …

Estimation Of In-Situ Compression Index Of Contaminated Clays Using The Electrical Method, Prasanna Ratnaweera

Theses

For contaminated clay soils, it has been found that current testing methods to determine compressibility characteristics do not truly identify the physico-chemiral interaction present in the soil-pore fluid-electrolyte system. Most methods are virtually impracticable due to various reasons such as evaporation of pore-fluid, difficulty of handling toxic chemicals, etc. Also, destructive test methods may not maintain in-situ conditions while testing.

The electrical properties of soils, the dielectric dispersion in particular is considered to represent the amount of physico-chemical interaction present in the soil-pore fluid-electrolyte system. For uncontaminated soils, correlations between the dielectric dispersion and the slope of the isotropic consolidation …

Estimation Of Modified Proctor Densities Based On Visual Identification, Ramesh Damodaram

Theses

Often in construction jobs requiring controlled compaction, there is a delay involved in testing the soil sample to be used as a structural fill. Here a rational approach has been adopted to get these values from 600 test data available. Using these data, appropriate relationships between grain sizes, maximum dry densities and optimum moisture content were developed. From these, two tables were derived to estimate the maximum dry density and optimum moisture content based on grain size distribution.

In a fill control job, if the borrow pit happens to change, the field personnel could obtain soil samples and send them …

Sorption Characteristics And Their Effects On Geotechnical Properties Of Clay Soils, Arambawattage Mahendra Rodrigo

Theses

An experimental investigation on the sorption characteristics of clay soils with liquid organics (phenol, chlorophenol, nitrophenol and chlorobenzene) and their effects upon geotechnical properties was undertaken. The investigation consisted of two different phases, namely, (1) the sorption/ desorption study, including kinetic rate, equilibrium time, isotherm modeling, and (2) geotechnical properties due to clay/ liquid organic interactions. The results of kinetic rate study indicate that the equilibration time for the contaminants way dependent upon the hydrophobic or the hydrophelic nature of the chemical. For equilibrium adsorption models, the linear isotherm was found to be the best fit in predicting sorption capacities …

Sorptive And Geotechnical Characteristics Of Kaolinite, Chi-Yuan Shih

Theses

The sorption/desorption behavior of phenol and chlorobenzene as well as their influence on geotechnical characteristics of kaolinite were studied. The results reveal that the sorption process follows closely with the Freundlich adsorption isotherm whereas the sorption/desorption ratio depends upon the characteristics of organic compounds.

A series of geotechnical properties tests was also undertaken after achieving equilibrium at different concentrations of organic compounds. It was found that the parameters such as liquid limit, plastic limit, optimum moisture content, and dry density increase with an increasing-concentration of organic compounds.

The relationship between the geotechnical, properties and sorption behavior of soils provides the …

Study Of The Structure And Capacity Of Construction Industry In Pakistan, Tayyab A. Ansari

Theses

The construction industry is the second largest sector in Pakistan's economy after agriculture. It is a fragmented industry which includes very small and very large contracting groups. It includes professional groups such as architects, engineers, management personnel etc. Major part of this industry is dominated by material's suppliers, vendors etc.

In the light of the developments which have taken place particularly over the last ten years, the study has covered the capacity of the construction industry in terms of estimated output, availability of manpower, demand and production of building materials , financial problems, credit, quality of work, the role of …