Civil and Environmental Engineering Commons^™

High Ammonia Strength Wastewater Treatment Using Algae, Bacteria And Ion Exchange, Nadezhda Zalivina

USF Tampa Graduate Theses and Dissertations

Nitrogen pollution has been considered one of the major problems of the 21st century. Discharge of nitrogen from improperly treated wastewaters into surface water bodies causes eutrophication and hypoxia, which results in significant environmental, public health and economic damages. In addition to the incoming flow, wastewater treatment plants generate internal highly concentrated ammonium streams, such as anaerobic digestion sidestream. As a current practice, sidestream without prior treatment is returned to the head of the plant, which increases the total incoming nitrogen load by 20-30% and often exceeds the treatment capacity. The most commonly used conventional biological nitrogen removal processes are …

Innovating Green Stormwater Infrastructure For Nutrient Management: Long-Term Field And Modeling Studies Of Conventional And Modified Denitrifying Bioretention Systems, Emma V. Lopez-Ponnada

USF Tampa Graduate Theses and Dissertations

Urban stormwater and nutrient management are increasingly important topics to address globally, as coastal urbanization increases, disturbing the natural landscape, hydrology, and water quality. Untreated urban stormwater runoff carries pollutants that enter our waterways, such as rivers and marine environments, which serve as drinking water sources, recreational sites, and locations for economic livelihood. One pollutant and nutrient of concern for water quality is reactive nitrogen (N). Since pre-industrial time, reactive nitrogen has doubled from human activity. When found in excess in waterways, nitrogen causes an overabundant growth of algae, which can result in eutrophic and hypoxic conditions, impacting ecosystems, human …

Implementations Of Resilience Engineering For Natural System Disturbances: A Panarchical Perspective, Mark Charles Stone Victoria Jaramillo

Civil Engineering ETDs

This body of work seeks to advance knowledge of resilience and resilience engineering (RE) from a practical and theoretical perspective. Three distinct applications of resilience and RE that align two fundamental frameworks are presented. The first application, a vulnerability assessment, exemplifies the largest scale of panarchy and the measuring aspect of RE. The second application, a Bayesian network approach, exemplifies the intermediate scale of panarchy and the modeling aspect of RE. The third application, an engineering design project using analytical hierarchy process (AHP), exemplifies the smallest scale of panarchy and the building aspect of RE. Studying these applications enriches understanding …

The Development Of A Novel Experiment On Confined, Flattened Brazilian Disks To Correlate Damage And Permeability In Brittle Geo-Materials, Samuel H. Boyce

Civil Engineering ETDs

This research develops a novel experiment using flattened Brazilian disks under confining pressure with concurrent permeability measurements and acoustic emission monitoring. The purpose of this work is to correlate damage and permeability in brittle geo-materials. Two series of tests are performed on concrete and one series on tuff, under a range of confining stresses between 2.76 and 13.79 MPa. Tests were continued beyond peak stress conditions, capturing data in the post-peak region. The acoustic emission data (cumulative energy and counts) are used to identify damage thresholds and track the progression of microscopic damage. This quantified damage is then correlated to …

Dynamic Prediction Of Runway Configuration And Airport Acceptance Rate, Yuan Wang

USF Tampa Graduate Theses and Dissertations

Automated prediction of runway configuration and airport capacity is critical for the future generation of air traffic management. In the future aviation industry, multi-sources weather forecast information will be available for air traffic decision-making units; how to use these data efficiently is key for overall efficiency of air traffic management. Currently, air traffic management personnel lack tools to assist them to translate weather forecast data into real-time airport capacity. Runway configurations and AARs of airports in a multi-airport system are determined by different air traffic controller personnel. The lack of synchronization may lead to the loss of efficiency of the …

Biointerfacial Studies Of Nitrifying Biofilms On Physically And Chemically Modified Surfaces, Philip Marley Roveto

Civil Engineering ETDs

Interactions between bacteria and surfaces during the initiation of biofilm formation are complex phenomena with significant and wide-ranging implications for nutrient cycling, ecosystem and human health, and the remediation of anthropogenic pollutants. Nitrifying biofilms are currently used for ammonia removal in wastewater treatment plant (WWTP) systems. As well-studied biofilms, they can serve as models towards understanding crucial aspects of biofilm engineering. The overall objective of this research was to better understand how variations in specific surface chemistries and topographical features affect nitrification rates and microbial populations in an effort to develop technologies for improved productivity. The experimental approach was to …

Imix Exz Wall Wp Residential Basement Waterproofing, Chad Clark

Building Academy Conference

No abstract provided.

Understanding And Utilizing Basic Codes, Rodney Johnson

Building Academy Conference

This presentation is designed for inspectors and design professionals, to have a basic understanding of how the various codes work together to accomplish a well designed and a safe building for the end user when completed and ready for occupancy. One code doesn’t fit all parts of the big picture of the design and inspection of the building during construction and at the final completion of the building prior to occupancy and one code does not address the future uses and maintenance of the structure without the assistance of the entire family of codes to support and complement one another.

Agricultural Rental Hall Wedding And Event Venues Party Barns, Sallie D. Fahey, Mike Wolf, Pat Grimes

Building Academy Conference

Rural event and wedding venues are all the rage, but many simply begin operation without proper code and zoning compliance. Rural property owners seldom understand that their old barn or new pole building was not built to Class 1 structure standards to allow public access, but when enforcement is initiated tearful brides and angry event planners blame local government. Other non-approved event venue owners are knowingly exceeding the limits and pushing enforcement of codes and public nuisance laws.

Advances In Remote Sensing To Understand Extreme Hydrological Events, Dongkyun Kim, Minha Choi, Jongho Kim, Ungtae Kim

Civil and Environmental Engineering Faculty Publications

No abstract provided.

Recovery Of Gypsum & Magnesium Hydroxide From Brackish Water By Chemical Precipitation, Sugam Tandukar

Civil Engineering ETDs

Exhaust gases from coal combustion contain contaminants such as sulfur dioxide (SO₂) and nitrous oxide (NO_x), and traces of other pollutants such as arsenic (As), mercury (Hg), nitrate (NO₃), and selenium (Se). Exhaust gas scrubbers are used to limit the emissions of these constituents to air. Treating exhaust gases to remove SO₂ is referred to as flue gas desulfurization (FGD), and the most common method is the use of wet scrubbers using limestone slurries. The limestone slurry is recycled multiple times in the scrubber, and to limit the concentration of dissolved constituents, a …

Enhancing Concrete Pavement Service Life Using Multiple Strategies To Reduce Cracking Potential, Dhanushika Mapa Mudiyanselage

USF Tampa Graduate Theses and Dissertations

Over the past years, prevention of cracking in concrete structures, especially at early age, has been a challenge facing transportation agencies. During early age, restraint of thermal and moisture related volume changes causes cracking in concrete. This research focuses on evaluating the effectiveness of different cracking mitigation strategies that can be implemented, in different concrete elements, to reduce early-age cracking incidents and therefore enhance concrete service life. To this end, a battery of field and laboratory testing were conducted, and finite element analysis was performed to better understand the mechanisms of primary significance on minimizing cracking risks commonly associated with …

Land Surface Temperature Variability Across India: A Remote Sensing Satellite Perspective, Satya Prakash, Hamidreza Norouzi

Publications and Research

Land surface temperature (LST) plays a key role in the surface energy budget computation and land surface process studies. The Moderate Resolution Imaging Spectroradiometer (MODIS) sensors onboard the Aqua and Terra satellites provide comprehensive global LST estimates at a fine spatial resolution. The MODIS products were recently upgraded to Collection 6, and shown to be more accurate than its predecessor Collection 5 products. In this study, LST and its variability have been examined across India from Collection 6 of the Aqua MODIS data at 0.05° spatial resolution for the period of 2003 to 2017. All-India mean LST characteristics show distinctive …

Damage Evaluation Of Full-Scale Rc Slab By Ultrasonic Tomography, Hiroshi Hayashida, Tamon Ueda

International Conference on Durability of Concrete Structures

There have been reports of road bridges that deteriorated after their RC slabs had been repaired. The insufficient removal of damaged materials is said to be the cause of such post-repair deterioration. Consequently, there is a call for a survey method that can detect deteriorated materials of bridges with high accuracy. Towards the development of such a method, this report focuses on ultrasonic tomography, because it can detect damage to the RC slabs of road bridges over relatively large areas. We examined the applicability of ultrasonic tomography to a method of assessing the RC slab damage by a test that …

Integrated Sensor Network For Monitoring Steel Corrosion In Concrete Structures, José Enrique Ramón-Zamora, José Manuel Gandia-Romero, Román Bataller, Ana Martínez-Ibernón, Isabel Gasch, Juan Soto

International Conference on Durability of Concrete Structures

The developed Integrated Sensor Network (ISN) allows a non-destructive monitoring of the rebar condition at different parts of the structure. The corrosion sensor allows the accurate determination of the corrosion rate (µm/year). Moreover, additional sensors are integrated in order to detect relevant changes in the concrete electrochemical condition.

The ISN has been published as an international invention patent (reference number WO 2016/177929 A1). The system is based on an economic, simple, reliable and durable technology, which makes its implementation viable on new and repaired reinforced concrete structures (RCS). Therefore, it is also possible monitoring non-accessible parts such as deep foundations …

Similarity Analysis Of Rebar Corrosion Under Different Electrochemical Accelerated Method, Chuanqing Fu, J Chen, X Jin, H Ye, Jun Zhu

International Conference on Durability of Concrete Structures

The concrete cover cracking caused by non-uniform corrosion of reinforcing bar is one of the most important reason for structure service performance degradation. The most widely used electrochemical accelerated corrosion methods include external and internal electrode methods. The reinforcement are used as anode in both methods. The different between two methods is the position of auxiliary. In external electrode method, the auxiliary is set outside the specimen, including three methods, i.e. samples whole/part submerged in saline, samples wrapped by sponge and steel mesh. The electrochemical mechanism of these four accelerated method were analyzed by using the FE software COMSOL. According …

Micro-Mechanical Analysis Of Corrosion Products Formed During Long-Term Carbonation Induced Corrosion Of Steel, Marijana Serdar, Dubravka Bjegovic, Valérie L’Hostis, Stéphane Poyet, Damien Féron

International Conference on Durability of Concrete Structures

During corrosion distinct types of corrosion products form, composed of different ratios of ferrous ions and oxide, hydroxides. Corrosion products have different physical and mechanical properties, mainly density, resistivity, volume and modulus of elasticity compared to iron. Knowing properties of corrosion products is indispensable for service life modelling of structures and can give valuable insight into the long-term corrosion propagation process. In this study micro-indentation method was used to evaluate mechanical properties of different layers formed during long-term carbonation induced corrosion of steel in concrete. Investigation was performed on three sets of reinforced concrete samples, that underwent corrosion during 50, …

An Experimental Study Of Concrete Resistivity And The Effects Of Electrode Configuration And Current Frequency On Measurement, Hayder Oleiwi, Yu Wang, Nan Xiang, Levingshan Augusthus-Nelson, Xianyi Chen, Igor Shabalin

International Conference on Durability of Concrete Structures

Electrical resistivity, a measurable parameter of the state of concrete, plays an important role in the assessment of reinforced concrete structures. An experimental study using two-electrode method has been conducted to evaluate the resistivity of Portland cement concrete. Internal and external electrodes were varied in order to understand effect of the electrodes configuration, where carbon fibre (CF) sheets were employed as the internal electrodes and CF and copper sheets were used as external electrodes. Furthermore, frequency of applied current was varied from low to high, to identify the most suitable frequency that can be utilized for stable and reliable results. …

Will Blended-Cement Systems With Similar Chloride Penetration Potentials Resist Similarly To Corrosion?, William Wilson, Vincent Labattaglia, Arezki Tagnit-Hamou, Luca Sorelli

International Conference on Durability of Concrete Structures

The capacity of concrete to prevent chloride ions penetration represents a key durability factor for steelreinforced structures exposed to de-icing salts and/or marine environments. Although blended-cement systems are commonly characterized with accelerated chloride penetration tests developed for Portlandcement concrete (e.g. the ASTM C1202 method), their microstructures and pore solutions are very different. This study aims to illustrate how the full potential of blended-cement systems to resist chloride ingress (and thus, chloride-induced corrosion) may not be justly disclosed by these accelerated tests using electrical current, even when tested after three months of curing. A Portland-cement-only mortar and five binary blended-cement mortars …

An Investigation On Moisture And Water Absorption In Cement Paste With Electrical Resistance Method, Manami Mizoguchi, Tatsuya Kitagawa, Totsawat Daungwilailuk, Yuko Ogawa, Kenji Kawai

International Conference on Durability of Concrete Structures

Moisture in concrete is one of main factors related to degradation and deterioration of concrete structure, and there are various moisture transport phenomena in concrete such as drying and absorbing. There are a lot of previous studies on the drying process of concrete to clarify the mechanisms of creep as well as shrinkage. However, few studies have been reported on the process of water absorption and moisture absorption although carbonation and chloride attack are strongly related to moisture and water absorbing. It is necessary to investigate moisture transfer in concrete in detail. This study investigated the moisture transfer in moisture …

Pore Characteristics And Computed Permeability Of Pastes Subject To Freeze-Thaw Cycles At Very Early Ages By X-Ray Ct, Ya Wei, Zehong Wu, Xiang Gao

International Conference on Durability of Concrete Structures

Freeze-thaw cycling can damage microstructure of concrete and reduce the service life of concrete structures. This is especially detrimental for concrete subject to freeze-thaw cycles at very early-ages, such as within the first few days after constructions. Typical low and high water-to-cement (w/c) ratio pastes are investigated experimentally and numerically in this study. The pastes are subject to freeze-thaw cycles at the age of 1, and 7 days and then sealed-cured to the age of 45 days. The pore size distribution is measured and quantified by X-ray computer tomography (CT) with high resolution. The permeability of the corresponding pastes is …

Investigation Of Microstructure Of Cementitious Materials Exposed To High Temperature By Non-Destructive Integrated Ct-Xrd Method, Takuya Mikami, H Takahashi, T Sugiyama

International Conference on Durability of Concrete Structures

Severe accident occurred in 2011 at the Fukushima Daiichi nuclear power plant and it can be assumed that the concrete building was exposed to high temperatures environment for a long time due to loss of the cooling function of the nuclear reactor. In order to prepare for the best scenario in the decommission plan, it should be first needed to clarify and evaluate the level of damage and deterioration of the contaminated concrete. To solve this problem, experiments were conducted for cementitious materials with the maximum temperature of 400 or 1000 degrees Celsius with durations of up to 2 hours. …

Influence Of Pore Structure On Relative Chloride Diffusion Coefficient In Unsaturated Cementitious Materials, Yong Zhang, Guang Ye

International Conference on Durability of Concrete Structures

Chloride-induced corrosion of reinforcement in concrete structures is a serious issue in engineering practice. This paper investigates the influence of pore structure on the relative chloride diffusion coefficient Drc in unsaturated cementitious materials. The effects of various pore features, including porosity, pore size, and pore connectivity, on the continuity of water-filled pores in unsaturated porous systems are analyzed based on the Kelvin law and water desorption process. In the experimental program, different cementitious materials (OPC, slag, fly ash, and limestone powder) were used to prepare paste and mortar samples. The Drc of the mortar samples (one year old) at various …

Development Of Engineered Cementitious Composites With Conductive Inclusions For Use In Self-Sensing Applications, Benny Suryanto Dr, Danah Saraireh Ms, Steven Walls Mr, Jaehwan Kim Dr, W John Mccarter Prof

International Conference on Durability of Concrete Structures

The mechanical and a.c. electrical properties of a new varietal of engineered cementitious composite (ECC) incorporating conductive inclusions are presented. Electrical measurements were undertaken over a wide frequency range while curing and when under uniaxial tensile loading to study the influence of ongoing hydration and multiple microcrack formation on the composite electrical impedance. When presented in Nyquist format, the work shows that conductive inclusions reduce the bulk resistance of the composite while enhancing its polarizability, transforming the classic, single-arc bulk response of typical cement-based materials to a two-arc response. The bulk resistance was shown to increase with time and damage, …

Self-Sensing And Self-Healing ‘Smart’ Cement-Based Materials – A Review Of The State Of The Art, Dhanada Mishra Phd, Jing Yu, Christopher Leung Phd

International Conference on Durability of Concrete Structures

The paper reviews recent research on self-sensing and self-healing cement-based materials as part of Smart Civil Engineering Infrastructures. Incorporated in Structural Health Monitoring systems, these materials are likely to play an important role in making future infrastructure robust, resilient and sustainable. Smart or intelligent cement-based materials have attracted extensive attention in the last decade or so with strong implications for improving structural durability and service life. Additions of carbon fibres, carbon nano-tubes and various nano-powders giving cement-based matrix electrical properties used for self-sensing have been known for over a decade and a half. In addition, the strong capacity of Strain-Hardening …

Diagnosis On Expansion Of Heat-Cured Precast Concrete Blocks Due To Delayed Ettringite Formation In Japan, Yuichiro Kawabata

International Conference on Durability of Concrete Structures

Delayed ettringite formation (DEF) in concrete causes internal swelling, which reduces the mechanical properties of concrete and can lead to issues with concrete structures due to potentially large expansive deformation. In order to address the issues of DEF-affected structures, proper assessment of the structures affected is important. However, petrographic diagnosis of concrete affected by DEF remains a controversial issue. In this paper, as case studies, diagnosis on precast concrete blocks suspected of experiencing DEF was carried out. The concrete blocks were made of white Portland cement, limestone gravel, and limestone sand mixed with copper slag. The blocks were excessively heat-cured …

Rehabilitation Of Low Rise Rcc Structure Along 9m High Retaining Wall, Aniruddha Nakhawa Er, Vivek Deshmukh Dr

International Conference on Durability of Concrete Structures

Mumbai is the financial, commercial and entertainment capital of India, facing bigger challenges in accommodating its over growing population day by day. The Mumbai City has population of 18.4 million over its 634 km2 area, ie. Almost 350 ft2/person. This enormous rise in population density has restricted the development to expand vertically. This also, results in growth of major slums, which is almost 62% of the population dwelling in slums. Subsequently, the authorities is in need of a large scaled Slum Sanitation Program, which utilize the scarcely available land for construction of Community Toilet Blocks with involvement of NGO’s and …

A “Double-Multi” Model For Electromigration Of Lithiums And Chlorides In Asr Affected Concrete, Qing-Feng Liu, Li-Xuan Mao, Zhi Hu, Jin Xia, Gan-Lin Feng, Long-Yuan Li

International Conference on Durability of Concrete Structures

Existing reinforced concrete structures experience severe durability degradation when subjected to alkali– silica reaction (ASR) and chloride attack. A special electrochemical rehabilitation treatment, containing lithium compound anolyte, has been developed to drive lithium ions into concrete as well as remove chlorides simultaneously, for mitigating both the ASR-induced cracks and the chloride-induced corrosion. Good performance of introduced lithiums in controlling ASR-induced expansion has already been proved. Unfortunately, the migration mechanism of lithium in concrete under an external electric field is seldom investigated in existing literature. In this study, with help of the “double-multi” model, the efficiency of impregnation of lithium ions …

Distribution Of Lithium Nitrite Injected Into Concrete And Its Asr Suppression Effect, Koichi Kobayashi, K Rokugo, Y Takagi, T Otani

International Conference on Durability of Concrete Structures

In this research, lithium nitrite was injected into ASR-deteriorated concrete specimens made with reactive aggregates in order to suppress further deterioration. The amount of injected lithium nitrite was set to three different levels, and the subsequent expansion behavior and area of lithium permeation were investigated. The area of permeation was checked using the coloring reagent TDI. It was found that the prescribed amount of lithium cannot be injected fully into the non-deteriorated specimens. When the lithium was injected at an early stage of deterioration, the area of permeation was small and the ASR suppression effect was small regardless of the …

Mortar Quality Assessment For An Iconic Building Repair In Sydney Australia, Ion Dumitru, Tony Song, John Sury, Tom Wenzel

International Conference on Durability of Concrete Structures

Remedial work for an iconic building in Sydney, Australia is currently being carried out. Two façade mortars, capable of matching the current exposed quartz aggregate finish and achieving a 40 years design life, are required. In order to ensure the quality of the imported quartz aggregates for this project, test have been carried out for particle size distribution, density, wet/dry strength variation, sodium sulphate soundness and Los Angeles Abrasion value. The two mortar mixes employed for repair work (Form & Pour and Hand Applied mixes) were comprehensively assessed for mix workability, compressive strength in warm and cold conditions, drying shrinkage, …