Civil Engineering Commons^™

Comprehensive Analytical Investigation Of The Safety Of Unsignalized Intersections, Kirolos Haleem

Electronic Theses and Dissertations

According to documented statistics, intersections are among the most hazardous locations on roadway systems. Many studies have extensively analyzed safety of signalized intersections, but did not put their major focus on the most frequent type of intersections, unsignalized intersections. Unsignalized intersections are those intersections with stop control, yield control and no traffic control. Unsignalized intersections can be differentiated from their signalized counterparts in that their operational functions take place without the presence of a traffic signal. In this dissertation, multiple approaches of analyzing safety at unsignalized intersections were conducted. This was investigated in this study by analyzing total crashes, the …

Managed Lanes Weaving And Access Guideliness, Chulsu Yang

Civil Engineering Dissertations - Archive

To maximize the potential for successful managed lanes (MLs) operations, there are critical design issues that require special attention. Adequate ML access spacing and length of the ML access opening are required for the preservation of freeway capacity, level of service, and safety. The traffic weaving from an entrance ramp to the general purpose lanes across to a ML access point and vice versa are effectively modeled as a two-sided Type C weave. The 2000 Highway Capacity Manual (HCM) methodology was calibrated for the major weave without lane balance or merging (standard Type C weave) but not for the two-sided …

Comparative Damage Of Different Truck Configurations On Jointed Plain Concrete Pavement, Tito P. Nyamuhokya

Civil Engineering Theses - Archive

This study estimated the damage done by trucks with 35 different configurations on a typical structure of a Jointed Plain Concrete Pavement. The configurations were proposed by New York Department of Transportation, the sponsor of this study. The generalized three dimensional finite element program Abaqus was used to calculate the response of linear elastic rigid pavement structure under truck loading. The loads for each truck case were placed at critical locations on the surface of the pavement to obtain the maximum tensile stresses at the bottom of concrete slab. The computed tensile stresses were used in Darter fatigue model (1977) …

An Integrated Damping And Strengthening Strategy For Performance-Based Seismic Design And Retrofit Of Highway Bridges, Kazi Rezaul Karim

Masters Theses

"In this study, a damping-enhanced strengthening (DES) strategy was introduced to retrofit bridge structures for multiple performance objectives. The main objectives of this study are (1) to numerically demonstrate the effectiveness of the anchoring mechanism of a constrained damping layer in the proposed DES system, and (2) to evaluate the performances of a highway bridge retrofitted with a DES retrofit technique of viscoelastic (VE) damping and carbon-fiber-reinforced-polymer (CFRP) strengthening components that are nearly independent under weak earthquakes but strongly coupled under strong earthquakes"--Abstract, page v.

Screw Connections Subject To Tension Pull-Out And Shear Forces, Ryan M. Francka

Masters Theses

"Currently, the behavior of screw connections subject to combined tension pull-out and shear forces is not well understood. An experimental study was conducted at Missouri University of Science and Technology to better understand the relationship or interaction between these forces. The test program evaluated four parameters that may influence the behavior of pure tension and pure shear in screw connections: the thickness of the sheet not in contact with the screw head, the ultimate strength of the steel, the ductility of the steel, and the screw diameter. This investigation extends the application of the pure pull-out and pure shear equations …

Anchorage And Bond Characteristics Of Externally Bonded Frp Laminates Used For Shear Strengthening Of Rc And Pc Girders, Carlos Andres Ortega Ordonez

Masters Theses

"In the last three decades, the use of fiber reinforced polymer (FRP) materials to strengthen structures externally has emerged as one of the most promising technologies in materials and structural engineering, and these materials have been gaining popularity in the civil engineering community. Externally bonded FRP sheets and laminates have been used successfully to increase flexural and shear capacity. The overall performance of the strengthened system depends heavily on the quality of the bond between the concrete and the FRP laminate. Low bond strength can cause delamination at the fiber-matrix interface and at the FRP laminate-concrete interface. As a result, …

In-Plane Behavior Of Strengthened Unreinforced Masonry Infill Walls With Alternative Wood-Fiber Fly Ash Material, Yosuke Tanizawa

Masters Theses

"This research investigates the potential for an alternative masonry product to use in masonry infill wall systems. The study also investigates the effects of an external fiber reinforced polymer (FRP) strengthening system on in-plane behavior of the alternative unreinforced masonry (URM) walls. The alternative masonry product is produced in a solid unit configuration and utilizes recycled white oak wood-fibers and an ASTM Class-C fly ash as its raw materials. The external strengthening system investigated consists of an elastomeric polyurea surface coating with and without integrated discrete chopped E-glass fibers which is directly sprayed on the URM wall surfaces. The alternative …

An Evolutionary Algorithm Approach To Actuated Signal Timing Optimization Under Lane-By-Lane Detection Condition, Eric G. Strack

Masters Theses

"Motivated by the need to reduce congestion on the nation's roadway network, this research seeks to determine when a new detection scheme at actuated signalized intersections may help. This new detection scheme is called lane-by-lane detection. It "looks" at traffic in all lanes individually to determine the traffic volume on the roadway. Specifically, the problems addressed are investigating alternate signal timings and investigating the traffic volume's effect on performance of the detection scheme. For the alternate signal timings, an Evolutionary Algorithm (EA) was employed to identify the optimal signal timing. This algorithm creates signal timings and tests them in the …

Synthesis Of Best Practices In Transportation Security, Volume I: Vulnerability Assessment, Haritha Reddy Venna, Jon D. Fricker

JTRP Technical Reports

Part I of the research focused on developing a methodology to identify and evaluate the most critical and vulnerable INDOT assets. This method aims at obtaining an index that reflects the vulnerability and criticality of an asset on the basis of multiple performance criteria. This methodology was tested on the seven INDOT districts. Because not all the factors that influence the vulnerability do have same weight, the analytical hierarchical process is used to obtain the weights for the criteria. Countermeasures are suggested as a part of the research to reduce the vulnerability of a given asset based on its relevant …

Mechanistic Evaluation Of Rubblized Pcc Pavements, Yigong Ji

JTRP Technical Reports

This report presents a mechanistic approach and procedures for determining layer coefficients to characterize the in-situ behaviors of rubblized pavements. This procedure was developed based on the 1993 AASHTO Pavement Design Guide utilizing Falling Weight Deflectometer (FWD) testing and in-place simulation using back-calculation layer modulus. In order to evaluate the rubblized pavement systematically, twelve constructed pavement sections were extensively tested by FWD annually after construction. The FWD data was processed using the proposed mechanistic procedure. In addition, statistical analysis was conducted to compare the pavement structure parameters each year, including layer coefficient and in-situ resilient modulus using Analysis of Variance …

Verification Of Nyslab A Software For The Analysis Of Jointed Pavements, Maryam Limouee

Open Access Theses & Dissertations

A significant amount of research and development has been conducted for decades to provide a tool for the design and analysis of jointed slabs on different types of foundations. ILLI-SLAB, JSLAB, EverFE and ISLAB are the most used finite element modeling (FEM) codes that have gone through several iterations of improvement. JSLAB has been maintained by the Federal Highway Administration (FHWA) and is distributed free of charge and there is significant interest in further improving the capabilities of that software package.

Researchers at the University of Texas at El Paso have been charged to implement several modifications in the latest …

Investigation Of Surface Fine Grained Laminae, Streambed, And Streambank Processes Using A Watershed Scale Hydrologic And Sediment Transport Model, Joseph Paul Russo

University of Kentucky Doctoral Dissertations

Sediment transport at the watershed scale in the Bluegrass Region of Kentucky is dominated by surface fine grained laminae, streambed, and streambank erosion; high instream sediment storage; and surface erosion processes. All these processes can be impacted by agricultural, urban, and suburban land-uses as well as hydrologic forcing. Understanding sediment transport processes at the watershed scale is a need for budgeting and controlling sediment pollution, and watershed modeling enables investigation of the cumulative effect of sediment processes and the parameters controlling these processes upon the entire sediment budget for a watershed. Sediment transport is being modeled by coupling the hydrologic …

Structural Behaviour And Analysis Of A Steel-Concrete Balcony Bracket, Sean Carroll

Theses

For commonly used moment connections, such as the various types of beam to column endplates, a large amount of information in relation to testing data and suggested design methods exist. Engineers can use this information to safely design such connections. When developing new and unique types of connections however, usually no prior testing information is available to engineers due to the unique design. At the present time, the most effective method of designing and developing any structural element or connection is through testing. Testing and detailed analysis of the results gives factual information on the behaviour of the structure, which …

Macroscopic Traffic Safety Analysis Based On Trip Generation Characteristics, Chowdhury Siddiqui

Electronic Theses and Dissertations

Recent research has shown that incorporating roadway safety in transportation planning has been considered one of the active approaches to improve safety. Aggregate level analysis for predicting crash frequencies had been contemplated to be an important step in this process. As seen from the previous studies various categories of predictors at macro level (census blocks, traffic analysis zones, census tracts, wards, counties and states) have been exhausted to find appropriate correlation with crashes. This study contributes to this ongoing macro level road safety research by investigating various trip productions and attractions along with roadway characteristics within traffic analysis zones (TAZs) …

Asset Management Application Towards An Improved Right Of Way Acquisition, Dora Oralia Francis

Open Access Theses & Dissertations

The purpose of this research is to discover a most suitable approach when the right of way acquisition process begins. As soon as it is known that the right of way acquisitions begin, speculations are made to parcels in order to increase the values of these parcel. Different types of speculations can be made, at a different phase of the right of way (ROW) acquisition process. The parcel cost can vary due to speculations according to the phase of the right of way acquisition process. To help assist the Texas Department of Transportation (TxDOT) on the right of way acquisition …

Assessing Repeatability Of Four-Point Bending Method For Estimating Fatigue Cracking Of Hot Mix Asphalt, Sara -. Montazeri

Open Access Theses & Dissertations

The objective of this thesis was to assess the repeatability of four-point bending method for estimating fatigue cracking of hot mix asphalt. This experimental research examined the influence of mix proportions, specifically asphalt and air void contents, on fatigue behavior of asphalt beam specimens in the laboratory tested with four-point bending method of loading. Following the relevant specifications, the strain-controlled mode of loading was selected. Fatigue failure is expected to occur at the cycle which the flexural stiffness of asphalt specimen reduced to 50% of initial amount. Up to a 1,000,000 cycles of loading were applied to each specimen.

Different …

Integrated Finite Element Analysis Program To Evaluate Pavement Performance And Predict Non-Destructive Testing Response, Cesar Tirado

Open Access Theses & Dissertations

The response of a pavement system under wheel loading has been a subject of research for many decades. Several models have been developed to predict pavement performance based on layer deformation and fatigue cracking. Among them stand out computer programs based on linear elasto-static layered systems and viscoelastic-plastic models; however, newer or more advanced constitutive models cannot be rigorously incorporated into them. In contrast, finite element techniques allow incorporation of nonlinear and viscoelastic-plastic behavior of the pavement materials but licensing of software and the need to train personnel greatly limits its use by highway agencies. A mechanistic-empirical (M-E) approach for …

Methodology To Develop A Minimum Cost Acceptance Sampling Plan For Highway Construction, Gandhar Wazalwar

Open Access Theses & Dissertations

Quality Assurance has always been a part of manufacturing processes. Since World War II, Acceptance Sampling has been introduced and implemented for quality control and improvement. Since statistical methods are applied for quality assurance, especially in acceptance sampling, various methods are becoming popular among the highway agencies over the period of time. As a result, several specifications have been designed to date based upon different statistical theories, each with its own advantages and shortcomings. Acceptance is a form of quality assurance which is employed as an audit tool for decision making to accept or reject the product based on its …

Estimating Variation In Stiffness And Volume Change Of Clays From Geochemical And Index Properties, Cynthia Roxanna Zuniga

Open Access Theses & Dissertations

Clayey soils from six different locations in Texas were analyzed and evaluated with respect to their expansion and shrinkage and change in stiffness associated with moisture content variation. These soils consist of five high plasticity-index (PI) clays (PI greater than 25) and one low-PI clay (PI = 17). The behavior of the clays changes dramatically with moisture content fluctuation, thus causing stiffness and volume changes throughout the year. Total or differential volume movements caused by swell or shrinkage strains of expansive soils and reduction in modulus can exert enough pressure to damage the pavements and cause maintenance problems.

The intent …

Gis-Based Tool For Assessing Hydraulic Performance Of Drainage Infrastructure System In El Paso, Gema L. Camacho

Open Access Theses & Dissertations

Maintaining a city's storm-water drainage infrastructure system can be an overwhelming effort, especially when data is inaccurate, incomplete, or located in disparate sources. This was the case for the City of El Paso. This research was part of a project funded by the City of El Paso to enhance their GIS storm drainage infrastructure system. For the first task of the project, the GIS software was used to store stormwater drainage data into one convenient GIS file. A GIS framework was created during the first phase of the project. This GIS database contained drainage data (such as location, material, dimensions, …

International Service Learning Projects For Senior Capstone Projects, Steve Reichle, Avery Bang, Carol Considine

Engineering Technology Faculty Publications

Service learning is being adopted in many engineering programs at various course levels. International service learning experiences can provide senior level engineering students with opportunities to practice the required skills of engineering graduates as detailed by the ABET Criteria for Accrediting Engineering Programs. Bridges to Prosperity is a non-profit organization that builds footbridges in rural third world communities. These design build footbridge projects require a full year for fundraising, site visit, design and construction, and provide engineering students an opportunity to practice their knowledge of globalization, sustainability, engineering design, teamwork, and leadership. A team of students from the University of …

Filterpave Systems, Purdue Ect Team

ECT Fact Sheets Archive

The need for hard-surfaced porous pavements has grown over the past few years as the market accepts PPS technology as a viable solution, as regulations leave few other options and as frequency of use increases. The FilterPave system is a unique porous pavement system that uses post-consumer recycled glass as the open-graded aggregate. Approximately 90 glass beverage bottles are used in just one square foot of pavement, making constructive use of abundant recycled materials that are traditionally sent to the landfill and used as daily cover.

Synthesis Of Best Practices In Transportation Security, Volume Ii: Emergency Response, Rodrigo Vargas, Jon D. Fricker

JTRP Technical Reports

Part I of the research focused on developing a methodology to identify and evaluate the most critical and vulnerable INDOT assets. This method aims at obtaining an index that reflects the vulnerability and criticality of an asset on the basis of multiple performance criteria. This methodology was tested on the seven INDOT districts. Because not all the factors that influence the vulnerability do have same weight, the analytical hierarchical process is used to obtain the weights for the criteria. Countermeasures are suggested as a part of the research to reduce the vulnerability of a given asset based on its relevant …

Saw-Cutting Guidelines For Concrete Pavements: Examining The Requirements For Time And Depth Of Saw-Cutting, Kambiz Raoufi, Tony Their, W. Jason Weiss, Jan Olek, Tommy E. Nantung

JTRP Technical Reports

Joints are placed in Portland cement concrete pavements (PCCP) to control random cracking. These joints provide a weakened plane that enables a crack to form in a controlled manner, relieving residual stresses that develop when thermal, hygral, or hydration movements are resisted by sub grade and adjoining pavement. While the concept of creating a weakened plane through saw-cutting is straightforward, determining the time and depth of the saw-cut has proven to be complicated. The goal of this project was to reduce the risk for joint raveling and random cracking. Specifically, this project has focused on: developing a procedure for determining …

Characterization Of A Mems Accelerometer For A Highway Health Monitoring Ultra-Low Power Sensor, Karla Cecilia Enriquez

Open Access Theses & Dissertations

With the 2009 American Recovery and Reinvestment Act, government officials recognized the need to implement automated methods that reduce the cost of assessment projects and provide a long-term solution to monitor the structural health of bridges and highways. Although important research exists in the area of non-destructive evaluation, current road health monitoring efforts continue to be costly and time consuming. This Thesis focuses on the characterization of a MEMS accelerometer intended to be the basis of a novel ultra-low power sensing system to remotely asses the condition of highways. The architecture of a sensor prototype built to validate an algorithm …

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Building Services Engineering

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Feedback Between Residual Circulations And Sediment Distribution In Highly Turbid Estuaries: An Analytical Model, Stefan A. Talke, Huib E. De Swart, H. M. Schuttelaars

Civil and Environmental Engineering Faculty Publications and Presentations

Motivated by field studies of the Ems estuary which show longitudinal gradients in bottom sediment concentration as high as O(0.01 kg/m⁴), we develop an analytical model for estuarine residual circulation based on currents from salinity gradients, turbidity gradients, and freshwater discharge. Salinity is assumed to be vertically well mixed, while the vertical concentration profile is assumed to result from a balance between a constant settling velocity and turbulent diffusive flux. Width and depth of the model estuary are held constant. Model results show that turbidity gradients enhance tidally averaged circulation upstream of the estuarine turbidity maximum (ETM), …

An Idealized Model And Systematic Process Study Of Oxygen Depletion In Highly Turbid Estuaries, Stefan A. Talke, Huib E. De Swart, Victor De Jonge

Civil and Environmental Engineering Faculty Publications and Presentations

The sensitivity of oxygen depletion in turbid estuaries to parameters like freshwater discharge, depth, and sediment availability is investigated using an idealized model. The model describes tidally averaged circulation and suspended sediment concentration (SSC), which are input into an advection–diffusion sink module of dissolved oxygen (DO). Based on the analysis of field data collected in the Ems estuary, the modeled oxygen depletion rates are proportional to SSC. The model is calibrated to the observed variation of DO with SSC and temperature. Modeled DO closely tracks changes to the estuarine turbidity zone (ETZ): increased channel depth, decreased freshwater discharge, and decreased …

Mitigation Of Impact Vibrations Using Impedance Mismatch In Cylindrical Structures, Sachiko Sueki

UNLV Theses, Dissertations, Professional Papers, and Capstones

The focus of this work is to study the phenomenon of material impedance mismatch to determine its effect on the mitigation of high frequency accelerations in projectile and long bar structures within linear ranges of materials. In this study, the acceleration responses of structures with various materials and material combinations were studied experimentally, numerically and by the Finite Element Analysis (FEA). Air-gun tests conducted by the US Army Research Laboratory were modeled using FEA to simulate the acceleration pulse and shock waves experienced by artillery components during a launch. After the prototype of projectile was selected, further studies were conducted …

Analysis Of A Caliche Stiffened Pile Foundation, Richard C. Stone Jr.

UNLV Theses, Dissertations, Professional Papers, and Capstones

Cemented carbonate deposits (known locally as "caliche") in Las Vegas have been used to support shallow and deep foundations with relatively high bearing pressures compared to soil. Most high rise structures in Las Vegas are founded on either a large mat or a long pile foundation. Recently, a new foundation type consisting of a short pile system bonded to shallow cemented layers was utilized for a large high rise building in Las Vegas and settlements during construction were recorded. The bonding of caliche layers together with short piles forms a caliche stiffened pile (CSP) foundation. The CSP foundation is unique …