Engineering Commons^™

Evaluation Of Fracture Principles In Asphalt Concrete Utilizing The Sc(B) Geometry, Airam Marlee Morales Vega

Graduate Theses and Dissertations

Since cracking is one of the principal distresses to be considered in asphalt concrete, multiple fracture tests and geometries have been used to quantify cracking resistance. One of the most popular geometries that have been used in fracture tests is the Semi-Circular bend (SC(B)). However, for this geometry, most of the fracture test methods use different parameters such as thickness, testing temperatures, and loading rates. Thus, the purpose of this research was first to evaluate fracture energy by performing a ruggedness test based on ASTM E1169. Then, to apply fracture mechanics concepts to evaluate three specimen thicknesses (25, 50, and …

Incorporating Geophysical Data In Slope Stability Modeling For Two Slopes In Arkansas, Vanessa Lebow

Graduate Theses and Dissertations

Slope failures in the United States alone cause millions of dollars in damage to infrastructure, threaten national monuments, create environmental hazards, and take an average of 25-50 lives a year. With the inevitable construction that occurs on slopes, it is imperative that the slopes be properly designed which requires a thorough understanding of slope grade, subsurface soil conditions, soil strength parameters, water table locations, and depth to bedrock across the entire site. The preferred method of data collection would be to use borings and other in-situ methods; however, sometimes due to cost constraints or site accessibility only a very limited …

Evaluation Of Concrete Deck Curing Regimens Using Capillary Pressure Sensing System, Samuel Spann

Graduate Theses and Dissertations

Early-age plastic shrinkage cracking is a common problem with the construction of concrete bridge decks due to the high surface area-to-volume ratio and exposure to potentially detrimental environmental effects. Curing regimens are utilized to mitigate cracking risk during the plastic stage of the concrete; the curing regimens evaluated for this study were wet burlap-polyethylene sheeting, two acrylic curing compounds, and one lithium compound. Capillary pressure in the water filled pores has been shown to correlate to the plastic shrinkage cracking risk of concrete. A new portable system has been developed to measure the capillary pressure that could potentially be used …

Truck Activity Pattern Classification Using Anonymous Mobile Sensor Data, Taslima Akter

Graduate Theses and Dissertations

To construct, operate, and maintain a transportation system that supports the efficient movement of freight, transportation agencies must understand economic drivers of freight flow. This is a challenge since freight movement data available to transportation agencies is typically void of commodity and industry information, factors that tie freight movements to underlying economic conditions. With recent advances in the resolution and availability of big data from Global Positioning Systems (GPS), it may be possible to fill this critical freight data gap. However, there is a need for methodological approaches to enable usage of this data for freight planning and operations.

To …

Study Of Internal Strains Developed In Concrete Decks At Early Ages In Steel Continuous Bridges, Fernando R. Benitez Ortiz

Graduate Theses and Dissertations

The Arkansas Department of Transportation (ARDOT) has identified bridge deck cracking shortly after concrete decks are placed and prior to applying traffic loads. Previous researchers have confirmed improper construction practices and design methods can lead to deck cracking. Currently, many contractors throughout Arkansas are using continuous deck pours. This construction approach may restrict the concrete slab from movement during early age shrinkage, causing tensile stresses to develop. The final stresses at the end of construction must be lower than the concrete tensile strength, if not cracking issues will develop. Eventually, these cracks may enlarge due to service load stresses and …

Development Of A Mechanical Device For Measuring Connection Rotations During Seismic Loading, Garrett Tatum

Civil Engineering Undergraduate Honors Theses

This engineering design project sought to design a cheap and easy-to-use sensor to monitor seismic connection rotations in steel buildings during earthquakes by using a linear ratchet mechanism. The idea for the project goes against the mainstream of research that is seeking to develop complex digital networks for monitoring structures in earthquake regions. Whereas many modern sensor networks require high-cost, professionally maintained digital networks, an analog sensor could provide much of the same information at a fraction of the cost, allowing sensors to be more widely utilized, particularly in developing countries. This project required an iterative engineering design process to …

Turbulent Effects On Building Pressure Using A Two-Dimensional Finite Element Program, Jonese Woods

Civil Engineering Undergraduate Honors Theses

Much of the knowledge about building aerodynamics today was obtained from physical testing like wind tunnel testing. Physical testing is time-consuming and very expensive. As a result, computational methods like the finite element method are being explored for use in building aerodynamics. Despite several years of research, there is still not a clear understanding of the peak pressure on buildings due to turbulence. Many of the research thus far has focused on comparing different computational methods. However, much work is needed in understanding the capability of the individual methods. In this work, a two-dimensional finite element program is used to …

Tension Splitting Strength Of Bcsa Concrete Cylinders, Andrew Steven Deschenes

Civil Engineering Undergraduate Honors Theses

The focus of this research was to compare the tension splitting strength (TSS) of belitic calcium sufloaluminate (BCSA) cement concrete to tensile strength predicted by the American Concrete Institute (ACI) and to similarly proportioned portland cement (PC) concrete. BCSA is a rapid-setting cement with higher early strength, higher ettringite content, and lower calcium silicate hydrate (C-S-H) content than PC. PC and BCSA cement concrete cylinders were broken at different ages in both uniaxial compression and TSS. It was found that BCSA had a similar TSS to both the ACI prediction and PC TSS, but the results require further testing for …

The Influence Of Citric Acid On Setting Time And Temperature Behavior Of Calcium Sulfoaluminate-Belite Cement, Edgar Soriano

Civil Engineering Undergraduate Honors Theses

Today the need to opt for alternative cementitious materials is growing due to environmental reasons and construction time frames that portland cement cannot always satisfy. Calcium Sulfoaluminate (CSA) cements are a strong candidate to supplement or replace portland cement in the construction field for certain applications. In the United States, CSA cement has been limited mostly to pavement repairs because of its rapid initial setting time. The chemical compound responsible for this phenomenon is the alumina. This compound and sulfate are present in larger proportions compared to portland cement. The purpose of this research is to study how the use …