Civil Engineering Commons^™

The Performance And Modification Of Recycled Electronic Waste Plastics For The Improvement Of Asphalt Pavement Materials, Baron W. Colbert

Dissertations, Master's Theses and Master's Reports - Open

Bulk electric waste plastics were recycled and reduced in size into plastic chips before pulverization or cryogenic grinding into powders. Two major types of electronic waste plastics were used in this investigation: acrylonitrile butadiene styrene (ABS) and high impact polystyrene (HIPS). This research investigation utilized two approaches for incorporating electronic waste plastics into asphalt pavement materials. The first approach was blending and integrating recycled and processed electronic waste powders directly into asphalt mixtures and binders; and the second approach was to chemically treat recycled and processed electronic waste powders with hydro-peroxide before blending into asphalt mixtures and binders. The chemical …

The Quantification Of The Fly Ash Adsorption Capacity For The Purpose Of Characterization And Use In Concrete, Zeyad Tareq Ahmed

Dissertations, Master's Theses and Master's Reports - Open

Fly ash has been shown to be an effective replacement for portland cement in concrete mixtures. However, many fly ash materials contain unburned carbon from the combustion process. Unburned carbon in fly ash adsorbs air entraining admixtures (AEAs) reducing their effectiveness in providing a specified air void system in concrete materials. Measurement tools and methods for characterization of the adsorption properties of fly ash materials are necessary for beneficial use of fly ash materials in concrete. In this research, two methods were developed to measure and quantify the adsorption capacity AEAs on fly ash materials. The first method is the …

Corrosion Of Post-Tensioned Tendons Repaired With Dissimilar Grout, Juan Carlos Rafols

UNF Graduate Theses and Dissertations

A failure associated with steel corrosion was identified in early 2011 in a bridge external post-tensioned tendon, approximately eight years after construction. Large voids in the grout and pockets of non-homogeneous material were identified. The non-homogeneous grout was characterized by high moisture content, and in most cases, the chloride content was lower than conservative threshold values. The non-homogeneous grout also had high pH and high content of sulfates (approximately in the range of 10,000-ppm). As a result, there was an interest in the study of possible corrosion development in repaired systems in which the affected tendons have been re-grouted with …

The Performance Of Irish Grown Timber Composites Under Fire Conditions, Cillian Murphy

Theses

In comparison with many European countries Ireland does not make the most effective use of its native timber. It is good economic and environmental practice to promote the more efficient utilization of this natural resource. In recent years there has been a revival in the use of timber in multi-storey construction which predominantly utilises load bearing exposed timber composite members. These timber composites are typically manufactured in Europe using European timber.

The current study investigates the viability of using Irish grown timber composites as a direct replacement in these load bearing members. The main areas of focus will be the …

Settlement Of Municipal Solid Waste, Emmet Burke

Theses

The mechanical properties of waste (compression index, elastic modulus, stresses) are an important aspect for the design, operation and post-closure uses of landfills. In recent years the requirement to utilise the acreage that the landfill occupies to its maximum potential has necessitated the landfill structure to accommodate a greater volume of waste over a smaller plan area. This pushes the boundaries of design relating to side-slope and infrastructural elements of landfill structures.

The objectives of this research were identified from significant gaps in the knowledge relating to the settlement and mechanical properties of municipal solid waste. The main objectives are …

Optimisation Of Cold-Formed Steel Purlin Cross-Sections, Matt Clifford

Theses

The subject of buckling of steel members is introduced and the critical nature of local buckling in slender members is highlighted.

The main thrust of work this semester is an investigation into the following buckling modes:

Flexural buckling;

Lateral torsional buckling;

Torsional buckling;

Shear buckling;

Web buckling;

Distortional buckling;

Local buckling.

This investigation has three main components:

1. Review of theory, books and appropriate published work;

2. Investigation into the relevant parts of Eurocode 3;

3. Finite element analysis using the LUSAS FE program to illustrate the various buckling modes.

Finally, the areas to be covered in the Realisation Stage …

An Analysis Of Dredge Material Reuse Techniques For Ireland, Colm Sheehan

Theses

This thesis examines the use and applicability of a range of dredge material management techniques for the Republic of Ireland which will ultimately assist the stakeholders in the industry in assessing the available dredge material management options. A detailed study is presented into the critical parameters required for successful implementation of a range of dredge material management options. An overview of the Irish dredging industry including current dredge material management practice is presented. This is complemented by a detailed critical analysis of the industry which identifies areas requiring development and future challenges for the dredging industry in Ireland. To further …

Shear & Torsion Behaviour Of Hollow-Core Pre-Stressed Concrete Slabs, Cian Twomey

Theses

Research Aim The aim of this study is to carry out research on shear and torsion behaviour of hollow-core slabs.

Research Objectives The objectives of the research are: • carry out a review of research literature published to date • carry out physical laboratory testing • generate and calibrate Unite element models • expand finite element models to model shear and torsion behaviour of hollow- core slabs • carry out a comparison and discussion of the findings

Distribution Analysis Of Freight Transportation With Gravity Model And Genetic Algorithm, Jun Duanmu, Peter Foytik, Asad Khattak, R. Michael Robinson

VMASC Publications

The application of a gravity model in freight modeling work on both short-haul and long-haul trips is discussed. A commodity-based gravity model was developed to assess the distribution of freight by long-haul trucks in southeastern Virginia. Although gravity models have been used extensively in transportation studies, little work has been done to address the special characteristics of freight transportation, such as the definition of friction factors and the differences between long-haul and short-haul trips. Results of a recent study of these and similar problems provide valuable insight into freight distribution modeling. A new calibration method that used a genetic algorithm …

Structural Identification Through Monitoring, Modeling And Predictive Analysis Under Uncertainty, Hasan Burak Gökçe

Electronic Theses and Dissertations

Bridges are critical components of highway networks, which provide mobility and economical vitality to a nation. Ensuring the safety and regular operation as well as accurate structural assessment of bridges is essential. Structural Identification (St-Id) can be utilized for better assessment of structures by integrating experimental and analytical technologies in support of decision-making. St-Id is defined as creating parametric or nonparametric models to characterize structural behavior based on structural health monitoring (SHM) data. In a recent study by the ASCE St-Id Committee, St-Id framework is given in six steps, including modeling, experimentation and ultimately decision making for estimating the performance …

Modeling Large-Truck Involved Crashes: An Econometric Modeling Framework, Mouyid Islam

Open Access Theses & Dissertations

This research aims to analyze large-truck involved crashes (i.e., having a gross vehicle weight rating more than 10,000 pounds) through the application of advanced econometric modeling techniques--namely, random parameter models (i.e., tobit regression, mixed logit). To achieve this, various national and state specific data sets are analyzed with the goal to provide an improved understanding of the complex interactions of contributing factors (e.g., factors related to drivers and occupants, vehicle, and road-environment) influencing large-truck crashes. Additionally, the modeling techniques considered in this research account for possible unobserved effects related to the data. The aforementioned econometric techniques provide an analytical foundation …

Carrier Collaborative Networks: Hybrid Hub Location Algorithms, Satyen Suresh Awale

Open Access Theses & Dissertations

Within the context of the Logistics and supply chain and management, the Hybrid Hub and Spoke system has certain complexities regarding the selection of the hub location in the supply chain facility system. The performance and efficiency of the network route selection and hub location depends upon the percentage savings that has been made by choosing the appropriate location for the hub to maintain the efficient flow of the goods within the network. Hub location selection mostly depends on the profit margins shared by the carrier, supply and demand status of the facility and amount of flow of the goods …

Methodologies For The Analysis Of Checked Baggage Inspection Systems, Nela Blejcharova

Open Access Theses & Dissertations

To enhance the security of the aviation system it is necessary to have a Checked Baggage Inspection System (CBIS) that is effective (that is, the highest possible detection probability or minimum false clear probability) yet efficient (that is, minimize the false alarm probability that causes inconvenience to passengers).

The first objective of this thesis is to review passenger, carry-on and checked baggage inspection procedures at airports

The second objective of this thesis is to develop a methodology using the optimization approach to set the optimal values of the sensitivity of the screening devices to minimize the total cost of inspecting …

Comparison Study Between Fem And Sem For Wave Propagation Models Applied To Solids, Shaddy Roberto Castillo Ponton

Open Access Theses & Dissertations

Wave propagation is a field whose application has spread across many disciplines. In the field of structural engineering, wave propagation methods have focused their attention specifically in the area of structural health monitoring and active control of vibrations and noise. Likewise, the development of new methods and their application have been successful in the area of material science with a special emphasis on the field of structural integrity evaluation of anisotropic and inhomogeneous structures (laminated composite structures). The current available analysis tools are inadequate to handle the modeling of complex structures. One-dimensional wave propagation problems in solids are still a …

Vulnerability Of Intermodal Logistic Networks To Sea Port Disruption, Jana Cervinska

Open Access Theses & Dissertations

Maritime trade is the backbone of international trade, specifically seaports which provide the gateway for the shipping and receiving of all international goods. Any disruption in operation can trickle down the global supply chain increasing costs and delay delivery of supplies. Hence, the objective of this work is the formulation of optimization models to study the vulnerability of intercontinental ports. Experiments are applied to container transportation between U.S. and Europe. The work differentiates itself from previous studies in that we analyze the vulnerability of the sea ports and compare how the closing of some ports or liner shipping lanes influence/impact …

Systematic Approach To Evaluate Potential Park And Ride Facilities, Lorenzo Emanuel Cornejo

Open Access Theses & Dissertations

Park and Ride (P&R) facilities promote transit ridership by providing an attractive option to car drivers. They enable potential users to drive to their locations where they can park their cars and take transit services to complete their destinations.

Although the concept of P&R has been implemented in many cities in the United States and integrated with different transportation modes such as mass rapid transit (MRT), light rail transit (LRT), high occupancy vehicle (HOV), Bus Rapid Transit (BRT), among others, no systematic approach has been developed to assess the feasibility of a potential P&R facility. This thesis proposes a systematic …

Calibration Of Concrete Pavement Performance Models, Alejandra Gallegos

Open Access Theses & Dissertations

Pavement performance models exist in various forms to cater to the pavement management agencies' needs and resources. Well-calibrated models are needed to accurately predict future pavement conditions, and to forecast and prioritize confidently the future rehabilitation and maintenance expenditures. Statistical tools are commonly used to develop the performance models. These statistical models may be impractical or misleading if not constrained with experts' opinions. This paper presents a hybrid technique where statistical tools and expert knowledge are combined for the calibration of pavement performance models. This technique was validated using historical pavement condition data for continuously-reinforced-concrete pavements (CRCP) from the Texas …

Sustainable Disposal Of Brine, Bijoy Krishna Halder

Open Access Theses & Dissertations

To meet growing water demand, more water is being harvested from nontraditional sources like brackish water from deep underground aquifers. Since these sources contain salts, drinkable water is produced by separating salt and other minerals (TDS, Total Dissolved Solids) from water through a process commonly known as desalination. A typical desalination plant produces 50-60% potable water from brackish water and the remaining water (brine) is disposed in evaporation ponds or by injecting it below the ground surface. To maximize the limited water supply, inland desalination plants have developed technologies to reduce brine production commonly known as zero liquid discharge (ZLD) …

Analysis Of Isolated Traffic Signal Control Systems, Petr Malina

Open Access Theses & Dissertations

Intelligent Transportation Systems (ITS) are implemented for increase of efficiency and safety in transportation. This thesis focuses on the area of traffic signal timing operations which is one of ITS components. The first objective is to compare the Czech and the U.S. methods for isolated fixed time traffic signal control, using an intersection in El Paso, Texas, as the test site. The second objective of this thesis is to evaluate the U.S. actuated isolated timing plan and compare it against the Czech and U.S. fixed time controls. A microscopic traffic simulation model of the selected intersection is coded in VISSIM …

Development Of Models To Estimate Modulus And Permanent Deformation Of Texas Bases, Eric Navarro

Open Access Theses & Dissertations

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