Civil Engineering Commons^™

Semi-Rigid Steelwork Connections, Conor Murphy

Theses

This thesis sets out to assess the stiffiiess of typical fin plate steelwork connections. The classification of joints as pinned, semi-rigid or fixed is described and the different models of moment-rotation relationship are explained. Eurocode treatment of steelwork connections is assessed with particular emphasis on joint stiffness. Procedures for the design of fin plate connections are set out and an example presented and a spreadsheet developed. Tests on a number of fin plate connections were carried out in the Heavy Structures Laboratory, to determine the moment rotation characteristics. The finite element software LUSAS was used to analyse the fin plate …

Seismic Tomography For The Integrity Assessment Of Earthen Dams And Levees., Leti Teklu Wodajo

Electronic Theses and Dissertations

Dams are a vital part of a nation's infrastructure. Considering the fact that many of the dams in the United States have approached or are approaching their projected life expectancy of 50 years, these critical infrastructures represent a risk to public safety. Minimizing this risk requires an ongoing safety inspection, monitoring, maintenance and rehabilitation program. This research examines the use of a non-invasive geophysical seismic method to provide additional information where the usual visual inspection is insufficient and the comboring investigation is not an option. Even though seismic techniques provide valuable information of the subsurface strata, the interpretation is not …

Estimation Of Pedestrian Safety At Intersections Using Simulation And Surrogate Safety Measures, Nithin K. Agarwal

University of Kentucky Doctoral Dissertations

With the number of vehicles increasing in the system every day, many statewide policies across the United States aim to increase the use of non- motorized transportation modes. This could have safety implications because the interaction between motorists and non-motorists could increase and potentially increasing pedestrian-vehicle crashes. Few models that predict the number of pedestrian crashes are not sensitive to site-specific conditions or intersection designs that may influence pedestrian crashes. Moreover, traditional statistical modeling techniques rely extensively on the sparsely available pedestrian crash database.

This study focused on overcoming these limitations by developing models that quantify potential interactions between pedestrians …

Evaluation And Recommendation Of Mix Design For Emulsion Stabilized Bases, Samuel Franco

Open Access Theses & Dissertations

Asphalt emulsion has been used for base material stabilization in a few TxDOT districts. Results from these practices were quite different. The initial performance of two projects on US287 constructed around 2000 in the Amarillo District has been found to be satisfactory. However, the Yoakum District has reported problems with asphalt emulsion for base work in a project on FM 237. The preliminary conclusion from these trials has been that asphalt emulsion may not perform well in the high humidity/high rainfall areas like east Texas. On the other hand, using calcium-based additives to stabilize base courses in road construction has …

Study Of Probabilistic Approach For Structural Health Assessment Of Aerospace Structures, Jose Antonio Garcia

Open Access Theses & Dissertations

Current practical approaches used in structural health assessment programs of aerospace structures involve performing a fracture mechanics analysis to verify the safe life of structural components. The analysis typically makes several conservative assumptions implemented by NASA fracture control standard practices for critical structural components. This well-established paradigm for fracture control follows a deterministic approach and, in some cases, the calculations may produce overly conservative remaining life estimates.

This thesis describes the results of a study to approach the health assessment challenge of several critical components using probabilistic methods. The probabilistic analysis takes the current deterministic model and identifies variables that …

Determination Of Critical Parameters For Solar Probe Plus Shielding, Sergio Rafael Mendez

Open Access Theses & Dissertations

A methodology to determine critical design parameters such as critical "design" particle size, and critical "design" impact speed for the shielding of the Solar Probe Plus spacecraft was developed in this thesis. Several critical components and surfaces of the spacecraft such as the Solar Array North, the Thermal Protection System, and the ISIS Instruments were analyzed in this study. The methodology determines the critical "design" particle size based on the required reliability or probability of no impact. Current NASA methods do not provide means to calculate critical "design" impact speeds for missions such as Solar Probe Plus, where the distributions …

Methodology To Convert A Transportation Planning Origin-Destination Matrix Into A Microscopic Traffic Simulation Origin-Destination Matrix, Jose Osiris Vidana-Bencomo

Open Access Theses & Dissertations

Microscopic traffic simulation (MTS) is a cost-effective approach for the evaluation of traffic conditions in urban highways networks. In MTS models, traffic demand that is entered into the network is specified by one or several Origin-Destination (O-D) matrices. A major challenge in the application of MTS for large urban networks is the specification of the O-D matrices. This dissertation proposes a methodology that may be used to transform a O-D matrix from a transportation planning model (which is based on Traffic Analysis Zone, or TAZ, and is readily available) into a O-D matrix for a MTS model (which is traffic …

Evaluation Of Nondestructive Technologies To Assess Presence And Extent Of Delamination Of Hot Mix Asphalt Airfield Pavements, Manuel Celaya

Open Access Theses & Dissertations

Sufficient bonding between the hot mix asphalt layers is essential to ensure the desired structural capacity of a pavement. Delamination or debonding problems are particularly more severe on airfield pavements, due to higher traffic loads applied by aircrafts. Further progression of delamination may result in stripping of the lower layers due to the intrusion of moisture or may develop other dangerous distresses such as foreign object debris. The existing nondestructive testing procedures and equipment that have the potential to address the problem were identified and their effectiveness and potential for success were evaluated. The Ground Penetrating Radar, Falling Weight Deflectometer, …

Impact Of Truck Suspension And Road Roughness On Loads Exerted To Pavements, Shahram Misaghi Bonabi

Open Access Theses & Dissertations

A software package, called IntPave, an Integrated Pavement Damage Analyzer, was developed at the Center of Transportation Infrastructure Systems at The University of Texas at El Paso with the capacity to calculate the pavement distress for flexible pavements under any type of traffic load, and to make a comparison of the level of distress caused by a standard and a non-standard, assuming statically exerted loading. However, what has been lacking is a tool to measure the dynamic impact on the pavement due to vehicle-road interaction. In this report, the interaction of truck suspension systems with the roughness of the road …

Adaptation Of Low Impact Design To The Desert Southwest, Abubaker Ali Alamailes

Open Access Theses & Dissertations

A low Impact Development (LID) practices were used to design an Integrated Management Practices (IMP) system for a residential lot .The design was adapted to the Desert Southwest region based on twenty years of climate data including precipitation and temperature for three representative cities: El Paso, TX, Albuquerque, NM, and Phoenix, AZ. In order to capture stormwater runoff close to its source and to provide as much stored water as possible for plants, LID practices including bioretention cells and vegetated swales were applied throughout the lawn. The purpose of the design is to maintain the pre-development hydrologic characteristics of the …

Analysis Of Peer Intersection Data For Arterial Traffic Signal Coordination Decisions, Christopher M. Day, Thomas M. Brennan Jr, Hiromal Premachandra, James R. Sturdevant, Darcy M. Bullock

Lyles School of Civil Engineering Faculty Publications

This is the author-accepted manuscript version of Day, C.M., T.M. Brennan, H. Premachandra, J.R. Sturdevant, and D.M. Bullock, “Analysis of Peer Data on Intersections for Decisions About Coordination of Arterial Traffic Signal,”Transportation Research Record: Journal of the Transportation Research Board, No. 2259, Transportation Research Board of the National Academies, Washington, D.C., pp. 23–36, 2011, copyright National Academy of Sciences.http://dx.doi.org/10.3141/2259-03

Its corresponding poster can be found here:http://docs.lib.purdue.edu/atspmw/2016/Posters/3/

Reliability, Flexibility, And Environmental Impact Of Alternative Arterial Offset Optimization Objective Functions, Christopher M. Day, Thomas M. Brennan Jr, Alexander M. Hainen, Stephen M. Remias, Hiromal Premachandra, James R. Sturdevant, Greg Richards, Jason S. Wasson, Darcy M. Bullock

Lyles School of Civil Engineering Faculty Publications

No abstract provided.

Improving Safety And Mobility At High-Speed Intersections With Innovations In Sensor Technology, Anuj Sharma, Darcy M. Bullock, Senem Velipasalar, Mauricio Casares, Jacob Schmitz, Nathaniel P. Burnett

Department of Civil and Environmental Engineering: Faculty Publications

A series of innovations has been made in the vehicle sensors field. Technologies such as IntelliDrive and radar-based smart sensors make it pos­sible to track each vehicle in proximity to an intersection. However, current technologies have limitations, such as lack of robustness, accuracy, or level of penetration. This paper assumes an accurate wide-area detector (WAD), which might be soon available, and highlights the potential benefits that might be derived in safety and efficiency of oper­ations at high-speed intersections from the deployment of the WAD. Two critical areas in which wide-area detection can lead to significant improvements are discussed: (a) location …

Role Of Information On Probability Of Traffic Conflict On The Onset Of Yellow, Nathaniel P. Burnett, Anuj Sharma

Department of Civil and Environmental Engineering: Faculty Publications

This paper examines the effect of information provided to drivers through advance warning flashers (AWFs) on driver’s probability of conflict at the onset of yellow at a high-speed intersection. AWFs are specifically designed to minimize the number of vehicles trapped in their respective dilemma zones at the onset of yellow. A probit modeling technique was used to establish dilemma zone boundaries. Based on the dilemma zone boundaries probability of a perceived conflict curves was computed and compared against actual conflicts observed at each of the studied intersections. The comparison between the actual and theoretical probability of conflict curves generated a …

Impact Of Signal Timing Information On Safety And Efficiency Of Signalized Intersections, Anuj Sharma

Department of Civil and Environmental Engineering: Faculty Publications

Signalized intersections are provided in traffic networks to improve the safety and efficiency of vehicular and pedestrian movement. There are various measures under education, enforcement and engineering headings that are being attempted to improve safety and efficiency of operations at a signalized intersection. Provision of signal countdown timer, a timer showing the remaining red and green time in a phase, is one such measure and is commonly adopted in India. However, studies on effects of countdown timer under Indian traffic conditions are very scarce. Traffic heterogeneity and lack of lane discipline makes transferability of models developed in other countries (with …

Experimental Damage Diagnosis Of A Model Three-Story Spatial Frame, Samantha Sabatino

Electronic Theses and Dissertations

Structural damage can be induced by a variety of events from short-term abnormal stresses to long-term natural aging. Detection of changes in a structure's ability to withstand subsequent loads can aid decisions on safety, repair, rehabilitation, and demolition. Dynamic property shifts can show internal cracks and minor damage before propagation or failure occurs, but only if a proper indicator is selected. In order to evaluate potential damage indices, a three-story metal frame building was constructed. Using Star Modal software, dynamic structural properties were obtained from modal decomposition on experimental tap test responses. The natural frequencies and mode shapes of the …

Column Capacity Evaluation For Low-Rise Moment Frame Steel Buildings In Mississippi Subject To Wind And Seismic Hazards, Yihong Shi

Electronic Theses and Dissertations

For the design of steel frame structures, AISC outlines approaches of second-order analysis. In this study, two of these approaches are considered: Amplified First-Order Analysis Method and Direct Analysis Method. The methods were studied using SAP2000. Amplification of moments in a two-story plane frame subject to a wind load case is computed using both methods and shown to be of comparable magnitude for small deformations. ASCE/SEI 7 and IBC provisions were used to develop lateral design load conditions for the frames. In this study, a hypothetical building was assumed to be constructed in four different locations (Southaven, Batesville, Jackson and …

Improved Joining Method For Segmental Prestressed Structures, Ralph Warren Jensen

Open Access Theses & Dissertations

This dissertation addresses the need for more robust and materially efficient structures, specifically structures that absorb higher levels of energy, can self-erect and which have variable reaction capabilities. These structures can take much higher levels of strain and loading compared to current technologies in reinforced concrete and carbon fiber composites. These structures are made using a novel method of joining segmental elements. A great advantage with this segmental structural system is it's survivability under overloaded conditions. During an impact, or concentrated pressure load, the structure will wrap around the impact zone thereby widely distributing the contact stresses. This function or …

Development Of A New Mix Design Method And Specification Requirements For Asphalt Treated Bases, Hector Antonio Hernandez

Open Access Theses & Dissertations

Asphalt stabilized bases in Texas are usually designed and constructed as per Item 292, "Asphalt Treatment (Plant Mixed)," of the 2004 Standard Specification book. This specification is a hybrid of base and hot mix asphalt concrete procedures and requirements, which are sometimes incompatible. In addition, this Item uses a specific Texas Gyratory compactor that is not readily available to all districts. Some districts have started using test method Tex-204-F, Part III, `Mix Design for Large Stone Mixtures Using the Superpave Gyratory Compactor." However, this procedure was originally developed to design Type A and Type B hot mix at 96% density …

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Building Services Engineering

No abstract provided.