Civil and Environmental Engineering Commons^™

A Gis Based Multi-Modal Multiple Optimal Path Transit Advanced Traveler Information System, Nicholas A. Koncz

Theses

A method for the design and use of a Transit Advanced Traveler Information System (TATIS) using an off-the-shelf Geographic Information System (GIS) is developed in this thesis. The research design included: 1) representing multi-modal transit networks in a digital form with schedule databases; 2) development of a multiple "optimal" path algorithm that takes into account walking transfers using published time schedules; 3) incorporating user preferences and penalties in the algorithm; 4) development of a user-interface with suitable output capabilities; 5) using the prototype for sample inquiries giving performance measures.

This prototype was developed using the Arc/Info GIS developed by ESRI, …

The Use And Evaluation Of Cleaner Wicks To Accelerate In Situ Bioremediation Of Organically Contaminated Groundwater And Soil, Brian Michael Sielski

Theses

The adaptation of Cleaner Wicks to accelerate in situ bioremediation of organically contaminated ground water and soil can be accomplished by making minor modifications to the Cleaner Wick design.

Once these changes in the Cleaner Wick design have been made the two primary ingredients necessary for aerobic microorganisms, nutrients and oxygen, can be delivered via the Cleaner Wick to the subsurface environment both above and below the water table to stimulate microbial growth and activity. Therefore, the microbial population will be able to biodegrade the target contaminants, rendering them harmless products such as carbon dioxide and water.

An adequate understanding …

Integration Of Surfactants And Time Release Nutrients With Pneumatic Fracturing Process, Atiqur Md. Rahman

Theses

The objective of this laboratory study was the development of two novel improvements to the pneumatic fracturing process which would extend its present application. The first involved use of surfactant during pneumatic injection, and the second was subsurface injection of "time-release" dry nutrient pellets for enhancement of in situ biodegradation.

Bench scale tests demonstrated that pneumatic fracturing can be successfully performed with air containing a surfactant solution (foam fracturing). The results showed that foam fracturing followed by increased the rate of surrogate contaminant removal from 8% to 10% compared with regular pneumatic fracturing. These increases were attributed to enlarged fracture …

The Influence Of Hydrodynamics And Particle Size On The Rejection Properties Of Ultrafiltration Membranes, Usama M. Shahin

Theses

A mathematical model based on the flow hydrodynamics is developed to calculate the treatment efficiency of ultrafiltration process. This model relates the treatment efficiency with the consideration of both fixed parameters and variable parameters. The fixed parameters are function of the intrinsic rejection coefficient, diffusion coefficient, and viscosity whereas the variable parameters can be related to the fluid velocity, volume flux, and cartridge dimensions. The model has been examined by solutions with solutes that have different molecular weights. The experimental data fits the proposed mathematical model very closely suggesting its suitability to evaluate the rejection efficiency in ultrafiltration. As such …

Behavior Of Concrete And Slender Reinforced Concrete Columns Under Cyclic Axial Compression With Bidirectional Eccentricities, Byong Youl Bahn

Dissertations

A rational analysis of reinforced concrete (R/C) structures requires satisfactory modeling of the behavior of concrete under general loading patterns. The behavioral characteristics of concrete dominantly depends upon its load history. For the study of concrete behavior, parametric study and experimental investigation into the behavior of concrete under load history of random cycles are performed. Through parametric study, the applicability of the previous concrete models is examined and a physically motivated modeling for the cyclic stress-strain relationships is proposed. The present modeling of concrete under general cyclic loading is initiated to provide substantial applicability, flexibility of mathematical expressions and furthermore …

Theoretical Evaluation Of The Break Off Test For Concrete, Arjuna Priyara Ranasinghe

Dissertations

Strength of concrete is normally measured using the standard cylinder or cube. The measured strength is used for design. The accuracy of concrete strength is frequently challenged, particularly in large concrete structures where size effect of the test specimens is attributed for the differences. Many nondestructive tests were developed to evaluate concrete strengths. In recent years, it was obvious that these tests are unreliable. As the infrastructure decays, more nondestructive tests are required to evaluate the existing structures.

The Break Off Test is a recently developed nondestructive test. Although substantial amount of experimental investigations have been carried out on this …

Behavior Of Biaxially Loaded Concrete-Encased Composite Columns, Pedro Ricardo Munoz

Dissertations

The theory of nonlinear behavior of biaxially loaded short and slender composite columns is used to study the load-deformation and moment-curvature of four pin-ended composite column specimens tested under axial compressive load and biaxial bending moments in a single curvature. The accuracy of the test results is verified by comparison with analytical results obtained by a method of analysis that includes the nonlinear material properties of concrete and steel and covers the ascending and descending branches of the linear segmented column specimen. A computational method is presented to model the analytical behavior of the biaxially loaded composite column. Its validity …

Fluid Flow Modeling For Pneumatically Fractured Formations, Deepak Nautiyal

Theses

This thesis investigates the flow of compressible fluids in pneumatically fractured formations. Pneumatic fracturing is a recently developed technique for increasing permeability in geologic formations by the controlled injection of high pressure air. The artificially induced fractures enhance the flow rate of liquids and vapors in the subsurface, and can be applied to in situ remediation of hazardous waste sites, and for other hydrogeological applications.

A flow model for discrete fractures is derived based on the assumptions of viscous, laminar fluid flow through planar fractures (Poiseuille type flow). The model takes into account non-linearity introduced by gas compressibility effects. Provision …

Modeling Arsenic Transformation In Clay Soils, Chao-Yi Chung

Theses

This project is designed to estimate the possible transformation forms of arsenic in clay soil. A computer model was established to simulate arsenic transformations. The amount of arsenic species adsorbed, dissolved, and the predominant soluble species are calculated by the model, which is mainly based on the Freundlich adsorption isotherm, solubility data collected by Keaton and Kardos, and pH-Eh diagram established by Ferguson and Garvis. The computer language used is Turbo PASCAL version 5.5.

The clay soil environment is considered to be in standard state: 25°C 1 atm. Environmental factors of the soil system which are accounted for by the …

Development And Evaluation Of A Nfweav Simulation Model For Weaving Areas Under Non-Freeway Condition, Wen-Min Pan

Theses

The development of a microscopic digital computer simulation model representing vehicle interaction at a weaving area under non-freeway condition is presented. Weaving areas are classified into two categories: 1. Weaving caused by merging and diverging of a ramp with an arterial, 2. On/off ramps connecting an arterial with a highway. The principal characteristics of the simulation model are the following: 1) a car following and lane changing model were used to represent vehicle movements; 2) an anti-collision check algorithm was developed for all vehicle movements; 3) driver merging urgency and follower courtesy model were developed for weaving vehicles. The simulation …

The Use Of Cod As An Indicator For Evaluation Of Pretreatment Of Nitrocellulose With Acid Hydrolysis, Han-Chung Lee

Theses

Nitrocellulose is a toxic waste by definition. It is widely used in military and commercial industries. Nitrocellulose fines escaped from the manufacture's process has created problems in receiving water. However, little information is available for the treatment of nitrocellulose. Nitrocellulose is difficult to treat by microorganisms without any pretreatment. Therefore, the main objective of this study is to use acid hydrolysis to break down this material before biological treatment, and find the optimal operation conditions in this process.

In this work, the results indicate that percentage of nitrocellulose decomposing in hydrolysis depends on types of acid, acid concentration, reaction temperature, …

Design, Construction, And Operation Of Water Treatment Plant Residual Monofills, Haitao Bian

Theses

Due to the stringent environmental regulations, landfilling becomes the most viable option for ultimate disposal of water treatment plant (WTP) residues. At present, most states apply the regulations for municipal solid waste (MSW) landfills to the landfilling of WTP residues. This is too stringent since the WTP residues are not hazardous. Therefore, development of suitable criteria for WTP residual monofills is necessary and urgent.

A set of environmental and geotechnical experiments was conducted to characterize WTP residues. It can be concluded that very little leachate will be produced and migration of leachate is unlikely. Also it was noted that insignificant …

Sulfuric Acid Resistance Of Fly Ash Mortar, Walairat Bumrongjaroen

Theses

Crown corrosion of concrete pipe and its subsequent repair is a topic much discussed in recent years. Present protective methods have not worked effectively. Due to its properties and its low cost, fly ash was used as a cement replacement of mortar to investigate its sulfuric acid resistance.

Different types and different percentages of fly ashes were mixed with and without admixtures including microsilica, and superplasticizer. The main parameters investigated included the chemical compounds, the fineness and the volume of fly ash. 2"x2" cubes were immersed in a 10% sulfuric acid pond. The weight of each cube was determined continuously …

Geotechnical Characterization Of Water Treatment Plant Residuals, Zhengyuan Xia

Theses

Evaluation of engineering properties of water treatment plant (WTP) residuals is a critical part in predicting their behaviors in monofills. In this study, ten WTP residual samples were collected from ten water treatment plants across the United States. Their general chemical/physical and geotechnical properties including liquid and plastic limits, compaction) shear strength, permeability and durability characteristics were determined.

It was observed that the geotechnical properties of WTP residuals are influenced by various factors such as mineral particle composition, organic content, type and amount of chemical additives) and time of aging, etc. Based on this study, the behavior of WTP residual …

Introduction Of An Information Feedback Loop To Enhance The Urban Transportation Modeling System, Kyle B. Winslow

Theses

The Urban Transportation Modeling System (UTMS) is a methodology used to estimate urban travel demand. This demand is measured as the volume of traffic that flows through a system of streets and highways. Through the use of traffic assignment software, parts of UTMS have become automated. One of the newest automated processes is the extraction of a subarea from a larger model. This extraction process is important to the local planner because it maintains a linkage from the regional model to the local model and it allows the user to extract an already distributed trip table rather than building one …

Attachment Systems For Curtain Wall Construction And Maintenance Requirements, Peter S. Donaghy

Theses

Curtain Wall construction has become a familiar and widely used method for enclosing structures. Since the 1950's this type of enclosure has become increasingly the most popular choice of Designers and Builders. During this period of development, however, acceptable and uniform building standards have not evolved to create adequate quality control.

This thesis investigates some of the design requirements of Curtain Walls, in particular the attachment system, and the maintenance costs that are directly related to the attachment system and the consequences of such failures.

Constitutive Equation For Concrete Using Strain-Space Plasticity Model, Yuxiang Xing

Dissertations

Plasticity theory has been used to model the concrete constitutive relationship for about two decades. With the modifications and refinement based on experimental data, achievement has been made in these plasticity models for concrete. Almost all the existing models are developed in stress space. With a lot of experimental data and more understanding about stress states of concrete, the stress-space model shows many advantages. Because of this and also due to conventional engineering practice, the stress-space plasticity approach has been in the dominant position. However, the conventional stress-space plasticity method has one inherent drawback in which it cannot deal with …

Tensile Behavior Of Concrete And Mortar Under Direct Impact Tensile Load, Kayumars Emad

Dissertations

Structures are often subjected to impact loadings during their lifetime. Most structural specifications including the special provisions for seismic design in the current ACI building codes, have been developed on the basis of quasi-static assumptions. Cement composites are strain rate sensitive materials therefore, their properties determined under quasi-static condition should not be used to predict their performance under high strain rates.

The objectives of this investigation are:

• to develop a standard test set-up for direct tensile testing of cementitious composites.
• to study the tensile behavior of mortar and concrete under direct impact tensile load.
• to develop a simplified formula to …

Unreinforced Masonry Structures : Nonlinear Analysis And Evaluation Of Some Rehab Schemes, Sanjay Mehta

Dissertations

Unreinforced masonry (URM) structures have been a common type of construction in the past and are still used in regions of low seismicity. Retrofitting of these structures is necessary because of two reasons: Firstly, observed damage after earthquakes reveals that URM construction is one of the most hazardous constructions even in the region of low seismicity; secondly, reclassification of seismic zones would require retrofitting of existing structures to comply with new guidelines for earthquake design.

Retrofitting measures require that the response of original and new structural systems as well as their interaction be considered. It is therefore important to correctly …

Utilization Of Fly Ash In Concrete, Chai Jaturapitakkul

Dissertations

Fly ash, a by-product of coal burning power plants, is produced in large quantities each year. It is commonly known that fly ash possesses pozzolanic behavior which can enhance the properties of concrete. Due to a lack of proper understanding on the formation of fly ash and its performance in concrete, the question of quality assurance has frequently been a major concern of engineers using fly ash in their construction projects. As a result, much fly ash is disposed of as waste material in landfills. Recent environmental concerns and a shortage of landfill space have rapidly escalated the disposal cost …

Integration Of Pneumatic Fracturing To Enhance In Situ Bioremediation, Conan Dante Fitzgerald

Theses

The purpose of this thesis was to study the anticipated benefits of integrating pneumatic fracturing with in situ bioremediation. Since pneumatic fracturing increases subsurface air flow in low permeability formations, it has the potential to overcome many of the major limiting factors of microbial growth and activity. A new innovation called pneumatic bio-injection can further enhance in situ bioremediation by efficiently dispersing biological solutions, including microorganisms, into a formation.

Bench scale experiments were conducted to examine the ability of microorganisms to survive the pressures and stresses associated with pneumatic injection. Tests conducted at pressures ranging from 60 to 500 psi …

Power Consumption In Single-Phase Agitated Vessels Provided With Multiple Impellers, Gwo-Ming Chang

Theses

A significant amount of data can be found in the literature on power consumption of single-impeller agitation systems. However, little and incomplete information is available for power consumption in multiple-impeller systems. Therefore, the main objective of this study is to experimentally determine the power consumed by multiple impellers in mixing vessels as a function of impeller type, impeller off-bottom clearance, impeller spacing, and agitation speed.

In this work, the power dissipated by combinations of one, two or three impellers of either identical types or different types was studied. The power drawn by each individual impeller was measured by means of …

Mechanism Of Pneumatic Fracturing, Trevor Compton King

Theses

This thesis investigates the mechanism of pneumatic fracturing in geologic materials such as soil and rock. Pneumatic fracturing is a recently developed technique for increasing the permeability of geologic formations by the controlled injection of high pressure air. Present applications are focusing on the in situ remediation of contaminated soil and ground water, although pneumatic fracturing has other geotechnical uses such as pumping well enhancement.

A comprehensive literature review of a related technology known as hydraulic fracturing is presented, which serves as background for development of a pneumatic fracturing model. Pressure-time histories from actual pneumatic injections are analyzed in detail …

Fracture Of Cementitious Composites, Sira Tindukasiri

Theses

Studies in fracture mechanics of concrete use a testing setup which tends to include unacceptably large errors in deflection measurements. Recent work reported by Kim [3] has proposed a new testing setup to eliminate these errors and consequently produce better determinations of fracture parameters.

The error which occurs most frequently is in the measurement of the load-line deflection. Until recently, the way this measurement has been made, using a dial gauge or LVDT (Linear Variable Differential Transformer) to measure the deformation between the center of the specimen and the frame, includes the crushing of the concrete surface at the supports …

The Permeability Of Hot Mix Asphalt Concrete With Petroleum Contaminated Soils, Kuen-Yuan Chuang

Theses

It is estimated by the United States Environmental Protection Agency (USEPA) that there are 2 to 3.5 million underground storage tanks (USTs) throughout the nation and about 25% of these tanks are leaking. The leakage of petroleum or other organic material presents serious environmental problem due to the uncontrolled release of petroleum products to ground water. Many new techniques have developed to reuse these petroleum contaminated soils generated from sites containing leaking USTs. One such soil reuse method available since 1985 is the use of petroleum contaminated soils in the production of hot mix asphalt.

The stability, durability, and hydraulic …

A Planning Model For Intermodal Auto-Rail Transportation Assignment, Daniel Disario

Theses

This thesis presents a planning model for assigning trips in a corridor served by highways and commuter rail. The underlying assumption is that commuters will choose a mode (or a combination of modes) connecting the origin and destination in a way that will either minimize their individual travel times and costs (the user equilibrium principle) or minimize total system travel time and cost (system optimal principle). The model is structured as a mathematical program with a non-linear objective function and linear constraints.

The model was applied to a case study of the Raritan Valley Corridor located in Northern New Jersey. …

Evaluation Of Truck Restrictions Using Simulation, Shaikh Mohamed Arif

Theses

Traffic congestion is a major problem in many central business districts. Many strategies have been proposed and implemented to solve or alleviate this problem. One of the most common strategies is to impose travel restrictions on the movement of trucks, without reviewing the economic consequences of goods movement restrictions on shippers, customers and on the overall business activity of the area.

This research examines the effect of various truck restrictive policies on the cost of urban goods movement, using the central business district of Manhattan as a case study. Computer simulation techniques are used to evaluate several scenarios under different …

Behavior Of R/C Columns Under Nonproportional Variations In Axial And Lateral Loads, Kaniz Fatema Ahsan

Theses

The study on the behavior of reinforced concrete columns subjected to the motion of earthquake suggests that the structure may experience nonproportional variations in axial and lateral forces. In order to assess the capacity of a reinforced concrete structure under nonproportional loadings, an analytical model is developed using the fiber modeling technique.

The method is based on detailed analytical description of the geometry and material properties used in evaluating the behavior of the critical regions rather than a simplified and predefined set of hysteresis rules. The present study has two principal components of investigation. First, the analyses are done at …

Development Of A Composite User Equilibrium And System Optimization Assignment Model, Kimberly M. Stump

Theses

The Urban Transportation Modeling System (UTMS) is a set of procedures used by transportation planners to predict the volume of traffic that will flow through a network, and how the traffic is routed. This paper will focus on the final component of UTMS, traffic assignment, which assigns the traffic flows to actual routes in the network.

In this paper, two composite models which model both User Equilibrium and System Optimal assignments are presented. The composite models are solved using the GAMS (General Algebraic Modeling System) software, a powerful mathematical programming tool. The first model was based on Beckman's Formulation, (Beckman, …

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 …