Civil Engineering Commons^™

Quantifying Workability, Compactability, And Cohesion Gain Of Asphalt Emulsion Cold In-Place Recycling, Sadie Casillas

Graduate Theses and Dissertations

To maximize the life and quality of a pavement, proper maintenance and rehabilitation are essential. Strategies for pavement rehabilitation with many sustainable benefits are pavement recycling. This dissertation focuses on two types of in-situ pavement recycling: Cold in-place recycling (CIR) stabilized with asphalt emulsion and full depth reclamation (FDR) stabilized with asphalt emulsion or foamed asphalt. One white paper (Chapter 2), two accepted peer reviewed journal articles (Chapters 3 and 4), and one submitted peer reviewed journal article (Chapter 5) are presented in this document to create better understanding of the unique material characterization of asphalt emulsion cold recycled materials, …

Verifying The Calcium Oxychloride Threshold In Cementitious Pastes, Fatoumata Traore

Graduate Theses and Dissertations

Calcium oxychloride (CAOXY) formation is a serious deterioration mechanism known to cause joint damage in concrete pavements. CAOXY is the product of a chemical reaction between calcium chloride (CaCl2) or magnesium chloride (MgCl) deicing salts and calcium hydroxide in the cementitious matrix. Currently, the accepted CAOXY threshold at which deterioration is mitigated in cementitious paste is 15 g/100 g paste (15 oz/100 oz paste); however, this limit was developed using flexural strength testing. For this investigation, the current threshold was evaluated using compressive strength and mass change over time in paste specimens exposed to CaCl2. Fly ash is used to …

Commodity-Based Freight Activity On Inland Waterways Through The Fusion Of Public Datasets For Multimodal Transportation Planning, Magdalena I. Asborno

Graduate Theses and Dissertations

Within the U.S., the 18.6 billion tons of goods currently moved along the multimodal transportation system are expected to grow 51% by 2045. Most of those goods are transported by roadways. However, several benefits can be realized by shippers and consumers by shifting freight to more efficient modes, such as inland waterways, or adopting a multimodal scheme. To support such freight growth sustainably and efficiently, federal legislation calls for the development of plans, methods, and tools to identify and prioritize future multimodal transportation infrastructure needs. However, given the historical mode-specific approach to freight data collection, analysis, and modeling, challenges remain …

Development Of An Improved Arterial Roadway Performance Reliability Methodology, Ernest Tufuor

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

The need for reliable performance measures of urban arterial roadways is increasing because of the rise in traffic congestion and the high value of travel time. Consequently, travel time reliability (TTR), which combines components of measures of central tendency and measures of dispersion of travel times, has recently received considerable research interest.

The basis of all TTR metrics is the travel time distribution (TTD). Estimating and forecasting arterial TTDs for TTR analysis is the focus of this dissertation. This dissertation proposes a new TTR methodology that is a marked improvement on recent TTR estimation and forecasting methodologies including the current …

South Texas Coastal Area Storm Surge Model Development And Improvement, Sara E. Davila, Cesar Davila Hernandez, Martin Flores, Jungseok Ho

Civil Engineering Faculty Publications

The intensification of climatic changes, mainly natural geophysical hazards like hurricanes, are of great interest to the South Texas region. Scientists and engineers must protect essential resources from coastal threats, such as storm surge. This study presents the development process and improvements of a hydrodynamic finite element model that covers the South Texas coast, specifically the Lower Laguna Madre, for the aid of local emergency management teams. Four historical tropical cyclone landfalls are evaluated and used as a means of verification of the hydrodynamic model simulation results. The parameters used to improve the accuracy of the model are the tidal …

The Use And Explanation Of The Phase Angle In Forced Vibration Testing, Nicholas R. Slavin, Ryan D. Thornton

Architectural Engineering

Forced vibration testing is a tool used to characterize a structure’s dynamic properties. When subjecting a structure to a forced harmonic load, the results help define the structure’s fundamental frequencies and dominant mode shapes. However, when conducting testing, it is difficult to determine the contributions of each mode to the response at a given location in the structure. The recorded response from a forced vibration test is a combination of unknown modal constituents. Excitation may not result in the pure, single mode response that the experimenter desires, but may instead result in a combination of modal responses that obscure the …

Case Study: Diesel-Powered Loaders Compared To Hybrid Loaders In Heavy Civil Construction, Jesus O. Pena

Construction Management

With the construction industry constantly changing, the environmental impacts of greenhouses gases have become a huge concern. Many contractors are adapting and switching over to hybrid powered systems to allow for more energy saving methods for heavy equipment, an increase in productivity, and efficient construction equipment that comply with emission regulations. The goal for this paper is to analyze the feasibility of heavy civil construction companies switching over from conventional diesel-powered wheel loaders to hybrid wheel loaders. Due to the competitive and saturated market in roadwork construction, many contractors have already begun to invest into hybrid systems. This provides cost …

Bs News July/August

Building Services Engineering

No abstract provided.

Performance Of A New Passive Damper For Seismic Protection Of Structures, Ghaedi Khaled

Student Works (2020-2029)

Passive energy dissipation devices have been successfully implemented in buildings around the world to reduce structural responses primarily to earthquakes, wind and other dynamic loads. Unlike active and semi-active control systems, passive systems make use of control devices that serve secondary functions. They are connected to structural members to increase structural damping without the use of external forces. The aim of this research is to introduce and investigate the performance of a new passive damper device called bar damper (BD), which is made of a number of solid bars sandwiched between two plates. The concept, placement and material properties of …

National Summer Transportation Institute: Increasing Career Awareness In Civil Engineering For Underserved High School Students, Melanie L. Villatoro, Janet Liou-Mark

Publications and Research

Our nation needs to increase the number of students pursuing degrees in the fields of Science, Technology, Engineering, and Mathematics (STEM) and those leading to transportation-related careers. In order to meet the demand for qualified graduates in transportation, it is necessary to diversify the pool of students entering college with an interest in these fields. The National Summer Transportation Institute (NSTI) is an educational initiative developed by the Federal Highway Administration (FHWA) and Department of Transportation (DOT). The NSTI at City Tech was designed to increase awareness of transportation-related careers among New York City high school students. The structure of …

Effects Of Physical And Chemical Characteristics Of Slags And Cements On Durability Of Portland Cement-Slag Blended Systems, Farzaneh Nosouhian

USF Tampa Graduate Theses and Dissertations

Ground granulated blast furnace slag (GGBFS) which is a commonly used supplementary cementitious material (SCM) needs to be more investigated for improving durability of concrete elements and service life of concrete structures. This research focuses on the effect of the physical and chemical characteristics of GGBFS and portland cement on durability of portland cement-slag blended systems. The effect of cement replacement level is also investigated using control mixes (no slag) and four different levels of slag content. To this end, eight GGBFS and eight portland cements were selected based on their physical characteristics and chemical composition. Four series of experimental …

Evaluation Of Temporal Damage Progression In Concrete Structures Affected By Asr Using Data-Driven Methods, Vafa Soltangharaei

Theses and Dissertations

Alkali-silica reaction (ASR) is a chemical reaction, which causes damage in concrete structures such as bridges, dams, and nuclear containments and powerplant structures. The ASR-induced damage may endanger the integrity and serviceability of structures. Several methods such as visual inspection, petrographic analysis, demountable mechanical strain gauges, and cracking index have been utilized for study the effect of ASR on structures, which are not always efficient in early damage detection and some are destructive and prohibited in nuclear structures. Nondestructive methods and structural health monitoring techniques can be alternatives for the condition assessment of structures. Among the nondestructive methods, acoustic emission …

Optimum Mixing Design Of Xanthan And Gellan Treated Soils For Slope Stabilization For Weathered Shales And Glacial Tills In Nebraska, Layal Bitar

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Verdigre located in North Eastern Nebraska experienced slope failures. The geological formations of theses slopes largely consist of several layers of weathered shales and glacial tills. It is believed that the weathering process reduced the shear strength of the soils leading to slope failures.

In this study, strength characteristics of Xanthan and Gellan gums treated soil specimens compacted at the optimum moisture content for field application were investigated so that the biopolymer treated soils may be properly used to stabilize the slopes. The untreated and treated samples were subjected to a wet-freeze(-6^oF)-thaw(167^oF)-dry weathering process up to …

Development Of A Mash Test Level 4 Open Concrete Bridge Rail, Jacob Delone

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

An open concrete bridge rail was designed and developed according to safety performance guidelines in the American Association of State Highway Transportation Officials (AASHTO) Manual for Assessing Safety Hardware (MASH) for Test Level 4 (TL-4). Systems designed and developed under previous guidance were studied, and their geometric information and full-scale crash testing performance was studied to establish the geometry of the new bridge rail. Yield-Line Theory and the AASHTO Post and Beam design methods were studied, and a modified version of the AASHTO Post and Beam method was utilized to determine the capacity of the new open concrete bridge rail. …

Freeways And Farms: Veggielution & Taylor Street Urban Farms Study, Joshua Baur, Ashley Estrada

Mineta Transportation Institute

This report presents the results of a project conducted by researchers at San Jose State University in partnership with Veggielution and Taylor Street Farm staff, funded by the Mineta Transportation Institute in San Jose, CA. The research team interviewed staff and volunteer farm workers to explore how nearby roadways impact experiences at farm sites. Research on outdoor nature-based recreation consistently identifies peaceful, natural site characteristics as important to a positive outdoor experience. This project sought to identify whether farm user attitudes and experiences would be consistent with these research findings resulting in farm users reporting that nearby roadways negatively impacted …

Congestion-Clearing Payments To Passengers, Paul Minett, John S. Niles, Richard W. Lee, Brittany Bogue

Mineta Transportation Institute

Peak period motor vehicle traffic volume congests roads all over the world. This project hypothesizes implementing congestion- clearing payments to passengers as a permanent congestion-management solution. Ongoing congestion-free travel would be achieved by removing existing congestion, and absorbing (re)generated demand, at costs that would be expected to increase as the total number of travelers increases over time. The project develops a comprehensive, step-by-step methodology to calculate the benefits and costs of paying for drivers to become passengers at a congestion-clearing level and to maintain this level over time. The method is derived from the literature, analysis by the project team, …

Estimating Flood Magnitudes Of Ungauged Urban Msimbazi River Catchment In Dar Es Salaam, Tanzania, Patrick Valimba Dr

Tanzania Journal of Engineering and Technology (TJET)

More often daily climate data have been used in hydrological models to estimate flood flows in small data scarce urban and rural catchments where flow peaking and recession are quick within short periods of few hours. This study assesses magnitudes of error of using daily climate data to simulate flood flow hydrographs of a small urban river catchment, Msimbazi River. Spot discharge measurements were available for Apr-May 2014 and Mar May 2015 periods.10-minutes climate records were available at one station, daily temperatures at two stations while daily rainfall records at several stations within the catchment. Visual analysis characterise rainfall events …

Data-Driven And Model-Based Methods With Physics-Guided Machine Learning For Damage Identification, Zhiming Zhang

LSU Doctoral Dissertations

Structural health monitoring (SHM) has been widely used for structural damage diagnosis and prognosis of a wide range of civil, mechanical, and aerospace structures. SHM methods are generally divided into two categories: (1) model-based methods; (2) data-driven methods. Compared with data-driven SHM, model-based methods provide an updated physics-based numerical model that can be used for damage prognosis when long-term data is available. However, the performance of model-based methods is susceptible to modeling error in establishing the numerical model, which is usually unavoidable due to model simplification and omission. The major challenge of data-driven SHM methods lies in data insufficiency, e.g., …

The Effects Of Surface-Water Flow On The Quality Of Groundwater And Surface-Water Systems, Quanghee Yi

USF Tampa Graduate Theses and Dissertations

My research has focused on the effects of surface-water flow on the quality of groundwater and surfacewater systems. For the first part of my research (Chapter 2 ), I s tudied the effects of s urface flow system changes in the water-conservation areas and canals in southeast Florida on the quality of groundwater in the surficial aquifer system.

For the second part of my research, by developing analytical models using the superposition method, I investigated the effects of bidirectional surface-water flow on the conservative contaminant concentrations (Chapter 4) and mean residence time (Chapter 5) in streams and rivers as well …

Structural And Agricultural Value At Risk In Florida From Flooding During Hurricane Irma, Alexander J. Miller

USF Tampa Graduate Theses and Dissertations

Flooding is the most costly type of natural disaster, as well as the most frequent. To provide risk-based flood insurance, providers such as FEMA must be able to accurately determine an asset’s risk of flooding. Additionally, after a flooding event, providers need to quickly determine the direct damages that occurred to verify insurance claims and provide assistance to the affected communities. Many current approaches to flood risk and flood damage estimation involve the use of data or statistical extrapolation that can add various sources of uncertainty into the final damage estimate. In order to reduce uncertainties in flood risk analyses, …