Engineering Commons^™

Analytical And Simulation Models Of Weaving Area Operations Under Non-Freeway Conditions, Muhammad Shahid Iqbal

Dissertations

The Highway Capacity Manual covers adequately the operation of weaving areas on freeways. Weaving on non-freeway facilities, however, has not been addressed as yet. This research effort presents a state-of-the-art procedural analytical approach and simulation models for the analysis of the level of service and operation of non-freeway weaving areas. Weaving under non-freeway conditions is classified into two broad categories; basic weave and ramp weave. The analytical models for these two weaving categories are calibrated and validated based on data obtained from several sites selected in the states of New Jersey and New York. New level of service criteria are …

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 …

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 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 …

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 …

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 …

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 …

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 …

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 …

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, …

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 …