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Adaptation Of Project Finance To Small Contractor Financing, Ragunathan Venkateswaran Dec 2002

Adaptation Of Project Finance To Small Contractor Financing, Ragunathan Venkateswaran

Masters Theses

One key reason for the poor performance of small construction establishments in securing a higher chunk of the annual project volume is funding. While construction industry does not require a large capital investment it does require a large working capital to start up the project and generate bills so that the resulting cash flow may take over the remaining funding requirements. Unfortunately for small contractors there are very limited options available from the banks or other lending institutions to cover this large working capital requirement in the absence of sufficient collateral. The "Project Finance" method, which has been used in …


Building Deconstruction Guidelines: Tools For Recovering Building Materials, Ali Ayedh Merzen Dec 2002

Building Deconstruction Guidelines: Tools For Recovering Building Materials, Ali Ayedh Merzen

Masters Theses

The traditional method of tearing down building when its life cycle is completed is known as demolition, which means destroying most of the structures and burying it in the landfills. This is the most common practice in most countries, but in recent years there is a new movement toward using the components of these buildings. Burying usable or recyclable materials in landfills means more pollution and increasing the need for more landfills. The concept of reusing or recycling building materials is known as Deconstruction. This practice is relatively new in the construction industry and requires more research and studies to …


An Imaging System For Concrete Bridge Inspection, Mohammed Talal Al-Bataineh Dec 2002

An Imaging System For Concrete Bridge Inspection, Mohammed Talal Al-Bataineh

Masters Theses

Bridges are the most important element in the road network because of, the strategic position a bridge occupies, its direct impact on safety, and its high cost. Therefore, a continuous maintenance and inspection should be performed. During the past years visual inspection has been the primary method of bridge inspection.

Pontis is a comprehensive bridge management system developed as a tool to assist in the challenging task of bridge management. Pontis stores bridge inventory and inspection data and formulates network-wide preservation and improvement policies for use in evaluating the needs of each bridge in a network.

The concrete bridge inspection …


Management Commitment To Construction Safety, Areen M. Shaar Dec 2002

Management Commitment To Construction Safety, Areen M. Shaar

Masters Theses

The objective of all businesses including construction is to make money and to be profitable. The costs resulting from personal injuries and equipment damage, combined with the associated financial impact resulting from schedule disruptions, insurance hikes, and workers compensation can definitely impact the profitability of any construction operation. Most times those costs can be minimized or avoided by giving safety more attention on construction job sites.

The main purpose of this research is to determine the correlation between management commitment to safety and its impacts on the frequency of injuries and illnesses. To achieve this, a survey was methodically developed …


Electronic Data Collection For Rockfall Hazard Evaluation, Derrick Ladon Bellamy Dec 2002

Electronic Data Collection For Rockfall Hazard Evaluation, Derrick Ladon Bellamy

Masters Theses

Rockfall field data collection traditionally has used conventional stationery tools, i.e. pencil and paper, for data collection. Traditional methodologies are being revisited with the advent of PDA’s (Personal Digital Assistants) or penbased computers. With the utilization of such technology, field data can be collected electronically. An electronic data collection system using PDA’s was developed for this thesis. The advantages of the PDA approach over pencil and paper data collection include automatic error and data integrity checks during data input, and the elimination of manual data entry. The PDA’s also allow automatic branching to solicit data input based on previous data …


Interface Behavior Of Water Saturated Limestone Rock Joints Using Hollow Cylinder Testing And A Case History Regarding Mine Roof Stability: Fort Hartford Mine Superfund Site, Roger W. Cecil Dec 2002

Interface Behavior Of Water Saturated Limestone Rock Joints Using Hollow Cylinder Testing And A Case History Regarding Mine Roof Stability: Fort Hartford Mine Superfund Site, Roger W. Cecil

Masters Theses

Presented herein is a multi-part thesis prepared to partially meet the requirements for the Master of Science degree in Civil Engineering at the University of Tennessee. Part I provides a brief introduction to the two primary thesis topics that are presented in Parts II and III, respectively.

Part II presents findings from a series of tests performed with a hollow cylinder combined axial-torsional testing apparatus to study the effects of confining fluid pressure on the shear strength of artificial rock joints for Holston Limestone. Tests were performed for confining fluid pressures of 0.14 MPa to 0.55 MPa and effective joint …


An Evaluation Of Facility Maintenance And Repair Strategies Of Select Companies, Christopher L. Sharp Sep 2002

An Evaluation Of Facility Maintenance And Repair Strategies Of Select Companies, Christopher L. Sharp

Theses and Dissertations

Although initial construction costs are high, the cost of operation and maintenance over a facilities life-cycle is significantly higher. A common challenge for facility maintenance professionals is balancing the cost of facility Maintenance and Repair (M&R) with the benefits derived from those facilities. This thesis documents how a selection of companies implemented that balance by determining their facilities requirements based on their chosen facility condition level and how they then allocated funds. The research effort consisted of interviews with facility maintenance professionals at each company selected. The data was then used to perform a multiple case study analysis and comparison …


Remediation Of Chromium Contaminated Soils With Colloidal Silica, Netnapid Yossapol Aug 2002

Remediation Of Chromium Contaminated Soils With Colloidal Silica, Netnapid Yossapol

Dissertations

The low-viscosity stabilizer, colloidal silica, is extensively used as a grouting material in the construction of grout curtains. It has low viscosity and is non-toxic, which is suitable for injection to stabilize fine-grained soils. It is also applied as a stabilizer in the in-situ treatment of hazardous waste. Once the colloidal silica solution is injected into contaminated soil, it moves through the pores inside the soil matrix, initiating the stabilization process. The viscosity of the colloidal silica mixture increases while it moves until solidifications. This process is called gelation and results in the creation of a gel barrier around contaminated …


Probability Of A Hazardous Material Truck Accident In New Jersey, Mahesh Damodaran Aug 2002

Probability Of A Hazardous Material Truck Accident In New Jersey, Mahesh Damodaran

Theses

Accident prediction modeling is a powerful tool for determining the frequency of accidents under certain circumstances. Nationwide, direct damages from highway hazardous material spills for the year 2000 were tallied at over $31billion. This thesis determines the probability of an accident involving hazardous materials on the roads of New Jersey. The methodology is based on a British predictive equation used by their Highways Agency to determine the probability of a hazardous spill over a section of a roadway. The parameters used by the British's Highways Agency, which is obtained from their accident data, were modified to reflect conditions that best …


Development Of A Model To Assess The Effect Of Ozone On Public Health Using Models-3/Cmaq, Pedro Alex Sanhueza H. Aug 2002

Development Of A Model To Assess The Effect Of Ozone On Public Health Using Models-3/Cmaq, Pedro Alex Sanhueza H.

Doctoral Dissertations

According to the Clean Air Act, the establishment of priorities in air pollution control should be based on benefits to public health and welfare. Given this mandate, EPA has incorporated the health effect evaluation in the regulatory impact analysis of its rulemaking, such as Tier2 sulfur gasoline reduction and HDE diesel emission reduction. The Tennessee Department of Environment and Conservation (TDEC) has identified ozone as the primary pollutant of concern. All these antecedents provided the basis for developing a decision-making tool that helps to evaluate the various regulatory options in controlling the emission of ozone precursors from a health-effects point …


Modification Of All-Hexadedral Finite Element Meshes By Dual Sheet Insertion And Extraction, Michael J. Borden Aug 2002

Modification Of All-Hexadedral Finite Element Meshes By Dual Sheet Insertion And Extraction, Michael J. Borden

Theses and Dissertations

The development of algorithms that effectively modify all-hexahedral finite element mesh is currently an active area of research. Mesh modification can be used to improve mesh quality reduce the time required to mesh a model, and improve the finite element analysis results. However, general modification of all-hexahedral meshes has proven difficult because of the global effects of local modifications. This thesis explains the global constraints on modifying all-hexahedral meshes and then presents three mesh modification techniques that make it possible to do local modifications while accounting for the global effects. These techniques are sheet insertion, sheet extraction, and mesh cutting. …


An Evaluation Of The Impact Of Lane Use Restrictions For Large Trucks Along I-40 Near Knoxville, Vasin Kiattikomol Aug 2002

An Evaluation Of The Impact Of Lane Use Restrictions For Large Trucks Along I-40 Near Knoxville, Vasin Kiattikomol

Masters Theses

This thesis is concerned with studies on an effectiveness and impact of lane restriction for large trucks from a left lane on Interstate 40 near Knoxville. The data collection was conducted in July to August 2001 and March to April 2002. The restriction was implemented on August 13, 2001. The lane distribution and individual speed of large trucks in each lane were then gathered to obtain patterns and characteristics of large trucks ‘before’ and ‘after’ the implementation. A database was developed, a data comparison was conducted, and a statistical test was applied. The findings reveal several significant changes of lane …


Interaction Of Silica Fume And Polypropylene Fibers In High Performance Concrete, May Tarek Massoud Jun 2002

Interaction Of Silica Fume And Polypropylene Fibers In High Performance Concrete, May Tarek Massoud

Archived Theses and Dissertations

The use of mineral admixtures and fibers is becoming essential in the new generation of high performance concrete since they introduce enhancement in mechanical properties as well as several durability aspects. Some of the advantages gained when properly employing high performance concrete are significant improvements in strength, drastically reduced permeability, better resistance to a wide spectrum of chemicals, superior performance in freezing and thawing conditions and enhanced thermal resistance. Although silica fume and polypropylene fibers are increasingly used in high performance concrete, yet, relatively little work has focused on the interaction of both ingredients in such concretes. The main aim …


A Model For Optimizing The Selection Of Project Delivery Systems Using Analytic Hierarchy Process (Ahp), Arosha De Silva Jun 2002

A Model For Optimizing The Selection Of Project Delivery Systems Using Analytic Hierarchy Process (Ahp), Arosha De Silva

Masters Theses

The project delivery systems applicable to the construction industry in the U.S. consist of different approaches. This study focuses on three main approaches, (1) Design-Bid-Build (DBB), (2) Design-Build (DB), and (3) Construction Management (CM). Since each construction project is unique, selecting the right project delivery system is a tough decision.

This study develops a decision making system, based on the Analytic Hierarchy Process (AHP), for selecting the best delivery system for a given construction project. AHP is a decision making mathematical model developed by Thomas L. Saaty and consists of a hierarchical structure. It analyzes several alternatives for a given …


Bi-Axially Loaded Slender Reinforced Concrete Columns Subjected To Sustained Loads, Song Gu May 2002

Bi-Axially Loaded Slender Reinforced Concrete Columns Subjected To Sustained Loads, Song Gu

Dissertations

A generalized analytical approach is presented in this research to predict the behavior both of slender and short reinforced concrete columns under sustained biaxial eccentric load.

The present analysis proposes equations established at a cross section of a reinforced concrete column by combining force equilibrium, constitutive law, and compatibility conditions. The strain and curvature of each section and the deflection of the column can then be obtained and resolved.

The established creep computation models, recommended separately by American Concrete Institute (ACI) 209R-92 and the Comite' Euro-International du Be'ton (CEB)-FIP 1990 Model Code have been used to calculate creep and shrinkage …


Complete Stress-Strain Characteristics Of High Performance Concrete, Insang Lee May 2002

Complete Stress-Strain Characteristics Of High Performance Concrete, Insang Lee

Dissertations

High performance concrete (HPQ has recently become a widely used concrete construction material for modem buildings, bridges, and pavements, etc. To produce such a better quality of concrete, chemical and mineral admixtures such as fly ash, slag cement, and silica fume, ground granulated blast furnace slag, as well as air-entraining agents are commonly used in the field construction. It has been found that high perforinance concrete can improve the workability, ultimate strength and durability of the concrete. However, the enhancement of ductility in concrete, and concrete structures as a whole is still inconclusive and needs more research. The ductility can …


A Bi-Level Programming Approach For The Shipper-Carrier Network Problem, Ya Wang May 2002

A Bi-Level Programming Approach For The Shipper-Carrier Network Problem, Ya Wang

Dissertations

The Stackelberg game betweenshippers and carriers in an intermodal network is formulated as a bi-levelprogram. In this network, shippers make production, consumption, androuting decisions while carriers make pricing and routing decisions.The oligopolistic carrier pricing and routing problem, which comprisesthe upper level of the bi-level program, is formulated either as a nonlinearconstrained optimization problem or as a variational inequality problem,depending on whether the oligopolistic carriers choose to collude orcompete with each other in their pricing decision. The shippers' decisionbehavior is defined by the spatial price equilibrium principle. Forthe spatial price equilibrium problem, which is the lower level of thebi-level program, a …


Impact Of Truck Regulation And 65mph Speed Limit On Truck Accidents In New Jersey, Rajat G. Rajbhandari May 2002

Impact Of Truck Regulation And 65mph Speed Limit On Truck Accidents In New Jersey, Rajat G. Rajbhandari

Theses

The state of New Jersey enacted two regulations with significant importance to the highway operations: 65 mph speed limit and truck restriction on the National Network. The speed limit of 65mph was used on limited sections of interstate system highways with an objective to reduce energy consumption by vehicles and truck restriction was used on the interstate system and other state highway system to reduce large truck accidents and thereby increase truck safety. In this research, the safety impacts of these two regulations on truck crashes were studied.

The research focused on monthly truck crashes along the highway sections where …


Finite Element And Pullout Test Performance Of Welded Wire Mats, Bradley C. Conder May 2002

Finite Element And Pullout Test Performance Of Welded Wire Mats, Bradley C. Conder

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This paper reports on the pullout test performance of welded-wire reinforcing mats. A 126-foot high mechanically stabilized earth wall was constructed at Kennecott Utah Copper. In the lower half of the wall, single lengths of 50-foot long welded-wire mats were used. In the top half of the wall, two lengths of 50-foot mats were overlapped 10 feet to create 90-foot mats. This 10-foot "lap zone" was investigated in this study.

The finite element program Plaxis was used to investigate several pullout test parameters: overburden pressure, gap width, boundary effects, and horizontal spacing of transverse elements from the pullout box face. …


A Novel Membrane Process For Autotrophic Denitrification, Agnieszka Pierkiel Apr 2002

A Novel Membrane Process For Autotrophic Denitrification, Agnieszka Pierkiel

Theses and Dissertations

This research focused on the novel use of hollow fiber membranes for gas delivery in biological dentrification using hydrogen-oxidizing bacteria. Autotrophic denitrification is a biological process that reduces nitrate to nitrogen gas using an inorganic carbon source. Hydrogen gas is an electron donor and nitrate is the electron acceptor in the reaction. The specific research objectives were to:

  • develop a mixed acclimated culture of hydrogen-oxidizing bacteria;
  • evaluate biodegradation kinetics of the acclimated culture;
  • evaluate hydrogen transfer characteristics of hollow fiber membrane modules;

and

  • demonstrate technical feasibility of a continuous bioreactor-membrane system for denitrification.

The following kinetic coefficients were obtained: µ …


A New Long -Term Design Model For Rehabilitation Pipe Liners, Shanyun Wang Apr 2002

A New Long -Term Design Model For Rehabilitation Pipe Liners, Shanyun Wang

Doctoral Dissertations

Thin-walled plastic pipe liners are routinely used to rehabilitate structurally sound host pipes that have lost their hydraulic integrity. Such liners are often installed below the water table and are consequently subjected to external hydrostatic pressure which may lead to creep-induced radial deflections and eventual collapse of the liner within the host pipe. Most of the current liner design model is based on the extension of short-term model to a long-term buckling liner design method. The objective of this thesis is to examine and provide a correction factor C* to allow short-term liner buckling models to be more accurately used …


Air Quality Impact Evaluation Of A Hypothetical Fire-Fighter Training Facility, William Glenn Fuller Apr 2002

Air Quality Impact Evaluation Of A Hypothetical Fire-Fighter Training Facility, William Glenn Fuller

Doctoral Dissertations

Human Health Risk Assessments (HHRAs) have become a required component in the permitting process for hazardous waste incinerators and boilers and for closure or evaluation of chemical and petroleum facilities. However, although not currently required, these evaluations are also essential for additional daily processes having the potential to adversely impact the environment. One such process includes emissions produced from a firefighter training facility. Firefighter training facilities perform scenarios to enhance the firefighting ability of the trainees. Three typical scenarios conducted at such a facility include air rescue and firefighting, building fire simulation, and propane system fires. During the course of …


Comparative Performance Of Rubberized Hot Mix Asphalt Under Alf Loading, Hanlin Qin Apr 2002

Comparative Performance Of Rubberized Hot Mix Asphalt Under Alf Loading, Hanlin Qin

Doctoral Dissertations

In response to the Intermodal Surface Transportation Efficiency Act (ISTEA) of 1991, Louisiana constructed five projects to evaluate several methods of using discarded tire rubber in highway pavements. The field performance was quite variable. To achieve the agreement among state agencies on the engineering benefits of using crumb rubber modifier (CRM) in HMA pavement and to define the circumstances where the LaDOTD can use asphalt rubber materials in the most cost effective way, a full-scale research program has been conducted at the Louisiana Transportation Research Center (LTRC) to evaluate the performance of CRM-HMA asphalt pavement under Accelerated Loading Facilities (ALF). …


Surfacing Splicing: A Method Of Quadrilateral Mesh Generation And Modification For Surfaces By Dual Creation And Manipulation, Benjamin Todd Grover Apr 2002

Surfacing Splicing: A Method Of Quadrilateral Mesh Generation And Modification For Surfaces By Dual Creation And Manipulation, Benjamin Todd Grover

Theses and Dissertations

The effective generation high quality quadrilateral surface meshes is an area of important research and development for the finite element community. Quadrilateral elements generally lead to more efficient and accurate finite results. In addition, some all hexahedral volume meshing algorithms are based on an initial quadrilateral mesh surface mesh that has specific connectivity requirements. This thesis presents a new and unique procedure named "Surfaced Splicing". Surface Splicing allows for the generation of all quadrilateral surface meshes as well as the ability to edit these meshes via the dual. The dual contains the same data as the mesh but, unlike the …


An Evaluation Of Geobest Contingency Beddown Planning Software Using The Technology Acceptance Model, Shawn J. Jensen Mar 2002

An Evaluation Of Geobest Contingency Beddown Planning Software Using The Technology Acceptance Model, Shawn J. Jensen

Theses and Dissertations

GeoBEST is a software program designed to simplify the contingency beddown planning process through application of geographic information technology. The purpose of this thesis was to thoroughly evaluate GeoBEST using prospective GeoBEST users in a realistic beddown planning scenario. The Technology Acceptance Model (TAM) was applied, which measures a prospective user's perceptions of the technology's usefulness and ease-of-use and predicts their intentions to use the software in the future. The evaluations also included a qualitative evaluation of specific software features. The test group for this thesis was seventy-one Civil Engineering students attending contingency skills training at the Silver Flag training …


Hexavalent Chromium Dissociation From Overspray Particles Into Fluid For Three Aircraft Primers, Richard A. Schilke Mar 2002

Hexavalent Chromium Dissociation From Overspray Particles Into Fluid For Three Aircraft Primers, Richard A. Schilke

Theses and Dissertations

DOD and industry use chromate-containing primers extensively to inhibit corrosion on metal assets. Chromate contains Cr6+, a human carcinogen, but there is little epidemiological evidence of increased lung cancer among spray painters. Using bio-aerosol impingers, overspray particles from three primers (solvent-borne epoxy, water-borne epoxy, and solvent-borne polyurethane) were collected into water to test the hypothesis that the paint matrix inhibits Cr6+ release into water, under the premise that this simulates Cr6+ release from particles into lung fluid. Particles were allowed to reside in water for 1 or 24 hours, then separated from the water by centrifugation, …


Evaluating Air Force Civil Engineer's Current Automated Information Systems, Edward P. Phillips Mar 2002

Evaluating Air Force Civil Engineer's Current Automated Information Systems, Edward P. Phillips

Theses and Dissertations

Almost every organization has some form of information system where data is captured and stored for later use. The Air Force civil engineering organization is no exception and is in the process of transitioning from the Interim Work Information Management System (WIMS) to the Automated Civil Engineer System (ACES). This research focused on users perceptions of both database and data importance to determine if significant differences existed between various user sub-groups. The research also attempted to identify the most frequently reported problems regarding system usage. The methods of analysis of variance and content analysis were used to answer the research …


Groundwater Flow Through A Constructed Treatment Wetland, Andrew C. Entingh Mar 2002

Groundwater Flow Through A Constructed Treatment Wetland, Andrew C. Entingh

Theses and Dissertations

This study examines the flow of groundwater through one of the treatment cells. A major goal of the study is to determine whether the system design facilitates uniform vertical flows through the subsurface soil sediments or if preferential flows occur. Conceptually, uniform flows will achieve the most efficient degree of contaminant removal possible by evenly dispersing the groundwater contaminants throughout the full volume of the subsurface media. A three-dimensional grid of piezometers is used to generate potentiometric contour maps, and in-situ tests of hydraulic conductivity facilitate construction of a numerical computer model. The contours of hydraulic head, measured conductivities, and …


Decision Analysis With Value-Focused Thinking As A Methodology In Structuring The Civil Engineer Operations Flight, Dee Jay Katzer Mar 2002

Decision Analysis With Value-Focused Thinking As A Methodology In Structuring The Civil Engineer Operations Flight, Dee Jay Katzer

Theses and Dissertations

The civil engineer operations flight organizational structure has been in a state of change since the flight's inception and is currently prescribed only to the element level. Therefore, an operations flight commander must determine the organizational structure best suited for their unique situation without any guidance or support. To provide insight and defensible support for an operations flight commander faced with this decision, a value-focused thinking process was used to create a value model that aids in evaluating possible organizational structures. To ensure that the results of this research are applicable across the Air Force, the value model was created …


Determination Of Chlorinated Solvent Contamination In An Upward Flow Constructed Wetland, Bryan C. Opperman Mar 2002

Determination Of Chlorinated Solvent Contamination In An Upward Flow Constructed Wetland, Bryan C. Opperman

Theses and Dissertations

The purpose of this study is to determine chlorinated solvent contamination levels in an upward flow constructed wetland at Wright-Patterson Air Force Base (WPAFB), Ohio. A stratified grid sampling methodology will be used in sampling the contaminated groundwater. Analysis will be accomplished by means of purge-and-trap gas chromatography. The contaminant concentration levels will be used to enhance the design and construction of man-made wetlands used to remove chlorinated solvents from aquifers. PCE levels declined from an average of 33.97 ppb in the inflow stream to an average of 3.65 ppb in the upper layer, a 91% reduction. High concentrations occurred …