Civil Engineering Commons^™

Transfer And Development Length Of Strands In Post-Tensioned Members After Anchor Head Failure, Elie El Zghayar

Electronic Theses and Dissertations

Post-tensioning tendons in segmental bridge construction are often only anchored within the deviator and pier segments. The effectiveness of the post-tensioning (PT) system is therefore dependent on proper functioning of the anchorages. On August 28, 2000 a routine inspection of the Mid-Bay Bridge (Okaloosa County, Florida) revealed corrosion in numerous PT tendons. Moreover, one of the 19-strand tendons was completely slacked, with later inspection revealing a corrosion-induced failure at the pier anchor location. Anchorage failure caused all PT force to transfer to the steel duct located within the pier segment that in turn slipped and caused the tendon to go …

Crack Detectability And Durability Of Coaxial Cable Sensors In Reinforced Concrete Bridge Applications, Genda Chen, Ryan D. Mcdaniel, Michael A. Brower, David Pommerenke

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The working mechanism and the measurement principle of topology-based crack sensors made of coaxial cables are briefly reviewed. The sensitivity, spatial resolution, and ruggedness of two coaxial cable sensors, respectively made of rubber and Teflon dielectric materials, were compared and validated with laboratory testing of a 4/5-scale, T-shaped, reinforced concrete beam-column specimen. Two Teflon sensors were installed on one of the solid decks of a three-span continuous highway bridge to investigate their durability and measurement repeatability. Laboratory tests indicated that both types of sensors have high sensitivity, but the Teflon sensor has a higher spatial resolution and a negligible spillover …

Indiana Pavement Preservation Program, Ghim Ping (Raymond) Ong, Tommy E. Nantung, Kumares C. Sinha

JTRP Technical Reports

State highway agencies are facing immense pressure to maintain roads at acceptable levels amidst the challenging financial and economic situations. In recent years, pavement preservation has been sought as a potential alternative for managing the pavement assets, believing that it would provide a cost-effective solution in maintaining infrastructural conditions and meeting user expectations. This study explores the potential of pavement preservation concepts in managing the agency‘s pavement assets by attempting to integrate pavement preservation considerations within the network-level pavement management system. Several elements are studied in the report: (i) determining triggers for pavement preservation treatments for use in a PMS, …

Evaluation Of Trenchless Renewal Methods For Potable Water Distribution Pipes, Abhay A. Jain

Civil Engineering Theses - Archive

Undoubtedly, potable water pipes, as part of an underground infrastructure system, play a key role in maintaining quality of life, health and well being of human kind. As these potable water pipes reach the end of their useful life, they create high maintenance costs, loss of flow capacity, decreased water quality, and increased dissatisfaction. Trenchless renewal methods (TRMs) are a medium to renew deteriorated potable water pipes, thus decreasing leakage loss, emergency maintenance costs and customer complaints. TRMs also maintain the quality of the water leaving the treatment plant. America's drinking water systems faces an annual shortfall of at least …

An Investigation Of Productivity Loss Due To Outdoor Noise Conditions, Shripad Dilip Maldikar

Civil Engineering Theses - Archive

Most people in day to day life at one time or other get irritated or distracted by surrounding noises. The irritation might have resulted in minor aggravation or may have been dramatic enough to hinder their work. This leads us to think whether there are any losses in the efficiency of construction workers due to surrounding varying noise conditions, or if they naturally adjust to their acoustic environment. In an effort to answer this question, this study on productivity loss due to varying sound conditions was conducted. It was found that, the efficiency of laborers was inversely proportional to the …

A Study Of The Strength Of Pervious Pavement Systems, Ikenna Uju

Electronic Theses and Dissertations

This thesis presents a study on the strength properties of the different pervious pavement systems installed at the Stormwater Management Academy field laboratory at University of Central Florida (UCF), Orlando. The strength tests were performed both in the laboratory and in the field. Laboratory testing was conducted to determine the compressive strength and flexural strength of the various pavement surfaces. Evaluation of field pavement performance was performed by comparing the deflection basins using the Falling Weight Deflectometer test on pervious concrete and porous asphalt with conventional impervious concrete and asphalt pavements of similar layer profile and thickness, respectively. From literature …

Feasibility Study Of Lightweight High-Strength Hollow Core Balsa-Frp Composite Beams Under Flexure, Kevin O'Neill

Electronic Theses and Dissertations

The United States of America's Military, more specifically the Army, has since the late 1990's had a vested interest in the development of super-lightweight, portable, short-span composite bridge and decking components to replace aging heavy metal-alloy machine driven modular systems. The following study looks at the feasibility of using balsa wood as the structural core material in fiber reinforced polymer (FRP) wrapped hollow-core composites in short-span bridge applications. The balsa provides shear resistance and the FRP the flexural resistance, resulting in extremely high strength-to-weight and strength-to-depth ratios. Several scaled short span specimens were constructed and tested using a variety of …

A Field Investigation For The Wind Load Performance Of Vegetated Greenroofs Using Monitoring Systems, Melike Minareci

Electronic Theses and Dissertations

Greenroof systems have been shown to be an environmentally friendly alternative based on various factors; such as, reduced lifecycle cost, improved air quality, ambient temperature reduction, stormwater management credit, sustainability and preservation of the environment. Recent research studies attempt to determine the construction methods of an ideal greenroof for environmental purposes, yet there is an absence of standards for the best design required to achieve acceptable structural performance and sustainability under wind loads. As a result, there is a need to document the effectiveness of greenroofs under high wind events by addressing the following questions: Do winds have an effect …

Performance-Based Plastic Design Of Earthquake Resistant Steel Structures: Concentrically Braced Frames, Tall Moment Frames, Plate Shear Wall Frames, Mohammad Reza Bayat

Civil Engineering Dissertations - Archive

It is well known that structures designed by current codes experience large inelastic deformations during major earthquakes. However, current seismic design practice in the U.S. is based on elastic structural behavior and accounts for inelastic behavior only in an indirect manner through certain modification factors such as R, I, and Cd. Under moderate to severe earthquakes, inelastic activity, including severe yielding and buckling of structural members can be unevenly distributed in the structure which may result in global collapse or costly repair work. Recently, a new design method has been developed and referred to as Performance-Based Plastic Design (PBPD). This …

Evaluation Of Project Delivery Methods For Trenchless Construction, Sahar W. Hasan

Civil Engineering Theses - Archive

The need of today's construction whether it be residential, commercial or infrastructure is to cut costs while maintaining schedule, scope, and delivering the expected quality. This realization has brought to light the importance of project delivery methods. Project delivery methods are no longer seen only as procedures to follow for a construction project; they have become instruments that are being used to save money, deliver projects ahead of schedule and come up with innovative design solutions by utilizing the contractor's expertise. This thesis evaluates the pros and cons of project delivery methods with respect to trenchless construction. Trenchless technology methods …

Investigating The Effects Of Various Crowd Characteristics On The Dynamic Properties Of An Occupied Structure, Robert Joseph Firman Iii

Honors Theses

One of the challenges for structural engineers during design is considering how the structure will respond to crowd-induced dynamic loading. It has been shown that human occupants of a structure do not simply add mass to the system when considering the overall dynamic response of the system, but interact with it and may induce changes of the dynamic properties from those of the empty structure. This study presents an investigation into the human-structure interaction based on several crowd characteristics and their effect on the dynamic properties of an empty structure. The dynamic properties including frequency, damping, and mode shapes were …

Development Of A Land Use Regression Model To Predict Nitrogen Dioxide Concentrations, Teresa Sosa

Open Access Theses & Dissertations

Air pollution is a major environmental concern in the El Paso-Juárez region. According to the Ministry of Environment and Natural Resources (Secretaría de Medio Ambiente y Recursos Naturales, SEMARNAT) the city of Juárez is one of the city's in México with the highest atmospheric levels of pollution because of its accelerated and unplanned urban growth. One air pollutant of concern is nitrogen dioxide (NO2) due to its detrimental health effects that have been associated with airway inflammation in healthy people and increased respiratory symptoms in people with asthma. Land use regression modeling is a GIS based approach that seeks to …

Determining The R Values For 12 Inch Deep Z-Purlins And Girts With Through-Fastened Panels Under Suction Loading, Kaye Dee Wibbenmeyer

Masters Theses

"Designing purlins for roof systems attached to through-fastened panels has been a subject well researched in the past. The current design specification uses a simplified approach to the designing of these members where the fully braced moment capacity of such members is multiplied by a reduction factor, commonly referred to as the R-value. This value represents the point in between the fully braced and fully unbraced member behavior. However, the current AISI Specification, S100, only contains R-values for purlins and girts up to 11.5 inches in depth. Since manufacturers are now rolling sections up to 12 inches deep, two confirmatory …

Nonlinear Finite Element Formulation Of The Soil Structure Interaction Through Two Parameter Foundation Model, Taraka Ravi Shankar Mullapudi

Masters Theses

"The response of shallow and raft foundations is having a significant importance due to its complex behavior because of the semi-infinite soil media. Winkler's model is the simplest model to deal with the structure and soil. The Winkler model represents the foundation reaction as proportional to the soil displacement at a particular point, which results in the elasticity of the soil being the only parameter in consideration. But in reality the soil cohesiveness is having a significant contribution in soil structure interaction, and therefore the consideration of coupling effects of Winkler springs need to be accounted. Most of the existing …

The Effectiveness Of The Natural Resource Conservation Service (Nrcs) And Huff Rainfall Distribution Methods For Use In Detention Basin Design, Todd Wayne Dablemont

Masters Theses

"This thesis focuses on the effectiveness of the NRCS and Huff rainfall distribution methods for use in detention basin design. This study required the use of HEC-HMS, hydrologic modeling software, in order to analyze the distribution methods. Three separate detention basins and their watersheds were modeled for this study. The watersheds were analyzed for both undeveloped and developed conditions. The parameters analyzed include detention basin inflow, detention basin outflow, watershed peak discharge, and detention basin storage capacity. The determination of detention basin effectiveness was based upon these parameters. The NRCS distribution method is widely used; however, many who use it …

Calibration Of Resistance Factors For Axial Capacity Of Driven Pile Into Missouri Soil, Mulugeta Abay Kebede

Masters Theses

"Over the past two decades the load resistance factor design (LRFD) has been accepted by the American Association for Transportation and Highway Officials (AASHTO) for the design of bridges. This approach is now gaining widespread popularity in the United States for substructure bridge design, including the design of driven pile foundations, as the states calibrate the geotechnical resistance factors for local geological conditions and practices. This study presents the geotechnical resistance factors calibrated for axially driven pile using the first-order reliability method (FORM) for the target reliability index of 2.33 and 3.0 based on 64 end-of-drives (EOD) and 22 beginning-of …

Experimental And Modeling Comparison Of Modular Photovoltaic-Thermal Solar Panels, Nicole C. Annis

Masters Theses

"Three different prototype photovoltaic-thermal panels using water as the cooling fluid were tested simultaneously. The first two panels (Panel A and B) consisted of a highly conductive thermal sheeting and different sized copper tubing. The third panel (Panel C) consisted of copper tubing with an aluminum fin. Thermal images were used to verify the heat transfer across the panels and compare the amount of heat radiating off the back of the photovoltaic-thermal panels versus the standard photovoltaic paneleaf Three A type panels were thermally connected in series. Three photovoltaic panels were also tested for an electrical comparison. The purpose of …

Innovative Concrete Bridging Systems For Pedestrian Bridges: Implementation And Monitoring, Kurt Edward Bloch

Masters Theses

"Two precast, prestressed pedestrian bridges were designed for rapid construction in Rolla, MO, utilizing high-strength concrete (HSC) and high-strength self-consolidating concrete (HS-SCC) with a target 28 day compressive strength of 68.9 MPa (10,000 psi) and release compressive strength of 24.1 MPa (3,500 psi). In addition, a glass fiber reinforced polymer (GFRP) bar reinforced deck panel system was utilized in one of the two deck panels on each bridge.

Material properties were tested for compression, elastic modulus, modulus of rupture, splitting tensile strength, creep, and shrinkage following ASTM standards. Instrumentation systems within the spandrel beams and precast deck panels were implemented …

Analysis Of Nationwide Intercity Travel Demand On The Us Transportation Network, Tao Li

Masters Theses

"In this thesis, three issues about the intercity travel demand on the US transportation network are addressed. The final one is the estimation of the domestic passengers' delay cost. A scheme is designed by assuming that costs incurred by flight delays relative to the original flight schedules are imposed at passengers' final destination airports. It is applied to estimate the total domestic delay cost of year 2007 and reasonable results arc obtained. The second one is the air travel demand estimation. Two route-based optimization models are proposed to estimate the travel demand based on available data. It is shown that …

Evaluation Of Variable Speed Limits Using A Genetic Algorithm Approach To Calibrate A Vissim Model, Brian Joseph Schaefer

Masters Theses

"The variable speed limit (VSL) system has been adopted on more and more roadways across the globe as an engineering tool for controlling traffic flow, particularly during congestion situations. An important and fundamental question raised among traffic engineers is: Are the costs of installing and operating variable speed limits really justified? In order to answer this question, this thesis measures the effectiveness of the VSL system applying the VISSIM microscopic simulation model to a non-recurrent congestion situation. For the analysis, a section of interstate was modeled in VISSIM and calibrated so that the simulated results closely reproduce the observed data …