Engineering Commons^™

Estado Esfuerzo-Deformación De La Estructura De Sostenimiento De Un Túnel A Partir De Un Modelo Físico, Henry Oswaldo Gómez Balceros

Ingeniería Civil

No abstract provided.

A Study Of Electricians' Preferences Of Pvc And Alternative Conduit Materials In The State Of Utah, Robert Andrus

Theses and Dissertations

Polyvinyl Chloride, commonly known as PVC is a common and effective construction material. PVC is also one of the most common types of plastic. In 2008, global production and consumption of PVC was approximately 34.5 million tons. The construction industry is responsible for about 70% of the world's consumption of PVC. The largest construction use of PVC is for pipe and conduit. Modern construction, especially structures built for data services depend heavily upon PVC conduit for underground pathways to distribute electricity and data. PVC is also at the center of a fierce effort by environmental groups who would like to …

An Improved Cube Cell Assembly For The Use With High Pressure/High Temperature Cubic Apparatus In Manufacturing Polycrystalline Diamond Compact Inserts, Kevin Christian Bach

Theses and Dissertations

The goal for this research was to reduce the current manufacturing cost of the polycrystalline diamond compact (PDC) inserts utilized in the natural gas and oil drilling industry while not reducing their current performance. Polycrystalline Diamond is added to the tungsten-carbide (WC) substrates commonly utilized in these applications because of its greater wear and thermal resistance. With the current cube cell design for the high-pressure/high-temperature apparatus, it is necessary to bond an extra WC substrate to the polycrystalline diamond insert to achieve the sizes generally ordered by the customers. The problem of bonding the extra WC substrate was solved by …

Variability In Construction Of Cement-Treated Base Layers: Probabilistic Analysis Of Pavement Life Using Mechanistic-Empirical Approach, Tyler J. Rogers

Theses and Dissertations

The primary objective of this research was to quantify the improvement in service life of a flexible pavement constructed using full-depth reclamation (FDR) in conjunction with cement stabilization when specified reductions in the spatial variability of specific construction-related parameters are achieved. This study analyzed pavement data obtained through field and laboratory testing of a reconstruction project in northern Utah. Data analyses included multivariate regression, Monte Carlo simulation, and mechanistic-empirical analyses of a model pavement structure. The results of the research show a steadily increasing trend in 28-day unconfined compressive strength of the cement-treated base (CTB) layer with increasing reductions in …

Construcción De Un Modelo Físico Para El Estudio Experimental De Los Efectos En Superficie Del Avance De Túneles Con Una Tuneladora Tbm-Epb En Suelos Blandos, Diego Armando González Vernaza, Jorge Bercid Lombana Rincón

Ingeniería Civil

No abstract provided.

Optimization Of Two-Way Post-Tensioned Concrete Floor Systems, Gaelyn B. Krauser

Master's Theses

This thesis investigates a parametric study of a flat plate floor system designed using post-tensioning. The load balanced by the post-tensioning, the slab depth, and the strength of concrete were varied to create the parametric study of a hotel/condominium grid layout. In order to perform the parametric study, research was conducted on the development of post-tensioning, methods of analysis for two-way slab design, and post-tensioning methods of analysis. Design was conducted by hand through a series of Excel spreadsheets and compared to results found using the computer analysis program, ADAPT-PT. The designs found in the parametric study were then used …

Evaluación De La Disipación De Energía Realizada Por Un Dispositivo Para Choque Frontal Contra Una Estructura De Concreto, Cesar Augusto Librado Castillo, José Luis Hernandez Manrique

Ingeniería Civil

No abstract provided.

Hot Mix Asphalt Longitudinal Joint Evaluation, Annette Porter

Civil Engineering Undergraduate Honors Theses

Longitudinal joints are the portion of the road where two lanes meet and are formed because the lanes are paved at different times. Longitudinal joints tend to be the weakest portion of the roadway, and yet few regulations exist to control their quality. Currently, Arkansas specifications for asphalt pavement do not include any requirements for the measurement of joint quality. The purpose of this research project is to determine the most effective method for evaluating longitudinal joints in hot-mix asphalt (HMA) pavements. Most of the literature concerning longitudinal joints focuses on density as the determining factor of quality because density …

An Economic Analysis Of Military Family Housing: Should The Government Continue To Privatize?, Chad A. Woods

Theses and Dissertations

Providing military family housing has always been a difficult task for the United States government. To solve the latest housing short fall, the government signed the Military Housing Privatization Initiative (MHPI) into law in 1996. Under this program the government contracts private developers to build, own, and operate housing units. The developer then collects rent through housing allowance payments. At the time MHPI was signed into law, military members were expected to pay 15 percent of their housing costs out of pocket. Subsequent legislation has increased housing allowance to provide 100 percent of all housing costs eliminating out of pocket …

The Utilization Of Light Gauge Steel In Residential Construction On The State Of Utah, Matthew Zaugg Perkins

Theses and Dissertations

This thesis researched why light gauge steel framing members are not used more in single-family residential construction. A survey was designed to extract information from licensed contractors in Utah on uses of light gauge steel framing members in residential homes. The purpose of the research was to discover what Utah builder's perception was concerning light gauge steel framing. Also, the researcher tried to learn a little about the contractors to see if there was a correlation between contractors that used light gauge steel and those that did not. Names of licensed general building contractors and residential contractors and their contact …

An Analysis Of Construction Contractor Performance Evaluation System, Rebecca S. Brown

Theses and Dissertations

A rigorous system for rating construction contractor performance does not exist for the USAF as identified by the Air Force Civil Engineer (USAF CE), Major General Del Eulberg (Eulberg, 2007). The United States Army Corp of Engineers (USACE) uses DD Form 2626 for contractor performance evaluation and contractor selection. The objective of this research is to strengthen the USAF contractor rating system by exploring USACE‘s use of DD Form 2626. Using data from DD Form 2626, statistical analysis was conducted to determine if the measured performance sub-items reflect their respective performance elements, whether the resulting performance elements relate to the …

Estudio Comparativo De Dos Alternativas De Reforzamiento Estructural Para El Edificio Maternal Del Liceo Frances Louis Pasteur, Utilizando El Método De Análisis Lineal Dinámico Y Un Método No Lineal Estático Pushover, Yessica Andrea Hernandez Morales

Ingeniería Civil

No abstract provided.

A Condition Assessment Approach For Buildings, Sally Maher Naguib El-Gizawy

Archived Theses and Dissertations

No abstract provided.

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 …

Thermomechanical Modeling And Optimization Of Friction Stir Welding, Manthan Malde

LSU Master's Theses

This thesis research implemented an existing thermomechanical model of friction stir welding process, and studied the surrogate model-based optimization approach to obtain optimal process parameters for the modeled friction stir welding process. As an initial step, the thermomechanical model developed by Zhu and Chao for friction stir welding of 304L stainless steel was replicated using ANSYS. The developed model was then used to conduct parametric studies to understand the effect of various input parameters like total rate of heat input, welding speed and clamping location on temperature distribution and residual stress in the workpiece. With the data from the simulated …

Quantity-Based Cost Forecasting System For Street Construction Projects, Nipesh Pradhananga

UNLV Theses, Dissertations, Professional Papers, and Capstones

Construction projects typically are not withdrawn after going into the competitive bidding process. The decision of contracting authorities regarding which projects will proceed to the bidding stage depends, in part, upon the early estimates of probable cost. Efforts are made to make this estimate as realistic as possible. Irrespective of the estimate of probable cost, the actual project cost is established by the amount of the winning bid.

This study analyzed historical bid data of street construction projects undertaken by the Public Works Department, Clark County, Nevada, from 1991 through 2006. The focus of this study was on utilizing statistical …

Neck Muscles Activity And Upper Body Extremity Angles In Dynamic Overhead Lifting, Mohamed Wassim Mokrani

LSU Master's Theses

Injuries of the neck and shoulders are common among workers who perform overhead tasks. In order to develop an injury-free working environment with regards to occupational musculoskeletal stress, it is pivotal to understand the pathophysiology of mechanical stress on the musculoskeletal system. The objective of this research was to study the effect of overhead lifting on the sternocleidomastoid and upper Trapezius muscles. Upper body joint angles were also analyzed using APAS during the overhead lifting. This study was conducted using two devices. The set of equipment incorporates an electromyography device, and the APAS. Two electrodes were placed at the muscle …

Assessing The Accuracy Of Task Time Prediction Of An Emerging Human Performance Modeling Software - Cogtool, Oluwakemi Damilola Adio

LSU Master's Theses

There is a need for a human performance modeling tool which not only has the ability to accurately estimate skilled user task time for any interface design, but can be used by modelers with little or no programming knowledge and at a minimal cost. To fulfill this need, this research investigated the accuracy of task time prediction of a modeling tool – CogTool - on two versions of an interface design used extensively in the petrochemical industry – DeltaV. CogTool uses the KeyStroke Level Model (KLM) to calculate and generate time predictions based on specified operators. The data collected from …

Effects Of Physical And Mental Tasks On Heart Rate Variability, Satya Anasuya Paritala

LSU Master's Theses

Demands at work are associated with an increased risk of cardio vascular diseases, but little is known about its underlying connection. The purpose of this study was to evaluate the effects of physical and mental tasks that induced stress, on Heart Rate Variability (HRV). Another aim was to observe the trends in subjective workload ratings in conjunction with the physiological response of the heart and also to assess the comfort level of the participants while wearing the heart rate monitor and performing tasks. Heart rate was recorded while at rest and while performing the tasks. Subjective workload ratings were obtained …

Hearing Assessment Of Forest Loggers, Antonio A. Fonseca

LSU Master's Theses

Forest logging is the process in which trees are cut down for forest management and/or timber harvest. According to OSHA, logging is the most dangerous occupation in the United States. It consistently represents one of the most hazardous industries, with a fatality rate more than 21 times higher than the rate for all workers in the United States. Yet, little research has been performed to determine the long term effect of noise on forest loggers. OSHA regulations state that the maximum permissible hearing in an 8 hour shift should not exceed 90 dB. Occupational noise exposure is recognized as a …

Laser Assisted Friction Stir Welding: Finite Volume Method And Metaheuristic Optimization, Shivani Daftardar

LSU Master's Theses

Friction Stir Welding (FSW) is a solid state joining process that uses a non-consumable rotating welding tool to generate frictional heat at the welding location. Large forces are required to produce friction between the welding tool and the work piece which increases the wear rate of the welding tool in welding materials with high melting temperature. Several different approaches have been developed to address this problem. This thesis focuses on a new modification of friction stir welding, called Laser Assisted Friction Stir Welding, a process developed in the last decade. This process uses laser energy to preheat the work piece …