Engineering Commons^™

Towards Multiple Model Approach To Bridge Deterioration, Jin A. Collins

Open Access Theses & Dissertations

The Intermodal Surface Transportation Efficiency Act of 1991 (ISTEA) marked the start of a new era in transportation in the United States. ISTEA required transportation agencies to take a proactive approach to planning and management of their assets. This included requirements for managing pavement, bridges, safety, congestion, public transportation, and intermodal systems. For horizontal transportation assets (i.e., bridges and pavement), deterioration modeling is an essential tool (Yanev and Chen 1993). Since ISTEA, Bridge Management Systems (BMS) have been utilized to inform decision-making regarding bridge projects such as maintenance, rehabilitation, and replacement (MR&R) under financial limitations (Agrawal, Kawaguchi, and Chen 2010). …

Assessment Of Point Of Use (Pou) Systems For Reducing Health Risks Associated With Drinking Water Along The U.S.-Mexico Colonias In The Paso Del Norte Region, Varinia Viridiana Felix Parra

Open Access Theses & Dissertations

In the Paso del Norte Region along the U.S. Mexico Border, there are more than 5,000 families living in impoverished communities known as colonias that lack access to basic infrastructure services such as a public water system. These depend on hauling trucks that deliver water into their storage tanks. Water storage practices by colonia residents on both sides of the border pose an enormous risk for waterborne disease outbreaks and heavy metal contamination because the water quality can decrease rapidly due to volatilization of the residual chlorine, intrusion of rainfall and air-laden dust. Since connection to centralized water treatment and …

Structural Design Of Complex Components, Armando Antonio Ochoa

Open Access Theses & Dissertations

The University of Texas at El Paso (UTEP) and the Center for Space Exploration and Technology Research (cSETR) is determined to develop a launch vehicle that is made completely of additive manufacturing materials, has the capability to transport a 100 lb payload to low earth orbit (LEO) as well as completing the design of a strucutral steel mobile launch stand that has the capability of withstanding the launch vehicle's static and dynamic loadings. The project will consist of carbon composite components to reduce weight while maintaining efficiency, strucutral steel components to resist extreme loadings and maintain strucutral shape, and lastly …

Quantifying Early-Age Concrete Mechanical Properties And Curing Conditions Utilizing An Automated System, Benjamin Arras

Open Access Theses & Dissertations

The validation of concrete quality based on the 28-day strength is a lengthy process. Predicting concrete mechanical properties through early-age methods can streamline the construction process. Early-age concrete behavior consists of assessing the concrete curing as-related to setting stages, the hydration process, strength and stiffness development, while considering various environmental system parameters. This paper reports on a nondestructive method for observing the early-age strength and modulus development of concrete mixes over seven days in a controlled, laboratory setting. An apparatus was designed and built for continuous acquisition of seismic modulus data (using free-free resonant column) and heat of hydration/maturity information …

Decision Support Tools For Parking Management On University Campuses, Okan Gurbuz

Open Access Theses & Dissertations

University campuses generate and attract trips with unique characteristics. Most universities are constantly challenged by the parking congestion issues. To manage campus parking infrastructure, most universities have established parking departments. This department is referred as the University Parking Office (UPO) in this Dissertation. There is no methodology or tool to assist the UPOs in their decision-making process. This Dissertation focuses on student parking and has developed models and methodologies as decision support tools to assist UPOs in managing student parking on campuses.

This Dissertation answers six Research Questions related to parking management on university campuses: (1) How many students are …

System Dynamic Model Of 1-Dimensional Unsaturated Water And Solute Transport For Predicting Salinity Stress In Crops, Thomas Poulose

Open Access Theses & Dissertations

There is a complex non-linear system dynamic between the water and salt transport in the unsaturated vadose zone where the salt transport and accumulation affect the water fluxes and vice versa. In addition, factors such as precipitation, transpiration, water infiltration and solute transport in the unsaturated zone of subsurface soil further complicate the processes involved. We have developed a system dynamics model for simulating the one-dimensional unsaturated water and solute transport along with root water uptake in the vadose zone. The model uses finite difference method for solving Richard's equation with a sink term for water transport and root water …

Load Rating Mobility As A Framework For Bridge Owners, Bryan Keith Stephens

Open Access Theses & Dissertations

In this time of financial economy, bridge owners are faced with the important decision of where to focus financial assets while attempting to determine which structures are in most need. Bridge Engineers and researchers alike agree that a large portion of the United States bridge population are reaching the end of their design life. Researchers are currently investigating various means and methods of lengthening the amount of usefulness of these key pieces of infrastructure. This paper introduces the novel idea of bridge Load Rating Mobility and how it can be leveraged by stake holders to assist in making those financial …