Effect Of Mixing On Monochloramine Formation Through In-Line Injection Of Chemicals In Water Disinfection Process,
2019
University of Texas at Arlington
Effect Of Mixing On Monochloramine Formation Through In-Line Injection Of Chemicals In Water Disinfection Process, Farhikhteh Samadi
Civil Engineering Dissertations - Archive
Addition of chlorine and ammonia to water for monochloramine formation in the secondary disinfection process in treatment plants has some challenges. Monochloramine formation as the only desirable product of the chloramination process is affected by several factors. These factors are pH, chlorine to nitrogen ratio and chemical mixing. In this study an investigation was conducted to measure the effect of mixing on monochloramine formation through direct injection of chemicals in a pipeline when keeping the other factors constant. In this study two sets of experiments were conducted. In the first study a tracer salt testing was used to find a …
On The Concept Of Synthetic Fiber Reinforced Thin-Walled Concrete Pipes,
2019
University of Texas at Arlington
On The Concept Of Synthetic Fiber Reinforced Thin-Walled Concrete Pipes, Arash Emami Saleh
Civil Engineering Dissertations - Archive
This research investigates the structural and industrial possibility to create a new type of concrete pipes called synthetic fiber reinforced thin-walled concrete pipes, which would be lighter, cheaper, and more durable than what is currently in use while still providing a pipe product much less dependent upon installation conditions than the very flexible metal and plastic pipes in the American market. The idea is to reduce the thickness and reinforcement of the current reinforced concrete pipes to increase their deflection before failure and control the crack formation and width by using synthetic fibers. The flexibility of these pipes will enable …
Development Of A Framework For Design And Installation Of Cementitious Spray Applied Pipe Linings In Renewal Of Corrugated Metal Culverts,
2019
University of Texas at Arlington
Development Of A Framework For Design And Installation Of Cementitious Spray Applied Pipe Linings In Renewal Of Corrugated Metal Culverts, Seyedmohammadsadegh Jalalediny Korky
Civil Engineering Dissertations - Archive
Millions of culverts under road embankments provide drainage for U.S. transportation network system and are in need of maintenance, repair, and renewal. Over time culverts, like any other asset, deteriorate due to many factors. Spray applied pipe lining (SAPL) is one of the trenchless technology methods applicable for culverts renewal. In the SAPL method, polymers or cementitious materials are sprayed by machine or manually in different lifts to achieve required thickness based on the design criteria. The scope of this dissertation includes reinforced concrete pipe and corrugated metal pipe (RCP and CMP) culverts renewal with cementitious and polymer SAPLs. The …
Rainfall Simulation For Investigating Hydrologic Responses To Storm Characteristics And Facilitating Frequency Analysis,
2019
University of Texas at Arlington
Rainfall Simulation For Investigating Hydrologic Responses To Storm Characteristics And Facilitating Frequency Analysis, Shang Gao
Civil Engineering Dissertations - Archive
Hydrologic and Hydraulic practices depend on the characterization of extreme precipitation that is rare in nature. Despite the advancement in sensing technology, the observation record of extreme rainfall with good spatio-temporal resolution has not reached a sufficient length. Furthermore, rainfall observation may never be sufficient in a non-stationary climate. Towards solutions to these issues, rainfall simulation was explored in this study (1) to investigate hydrologic responses to storm characteristics and (2) to facilitate rainfall frequency analysis. To that end, this study initially employed storm transposition plus hydrologic simulation for generating possible rainfall-runoff scenarios which further reveal relationships between storm characteristics …
Utilizing The State Of Art Technologies To Assess And Address Urban Flooding,
2019
University of Texas at Arlington
Utilizing The State Of Art Technologies To Assess And Address Urban Flooding, Daniel Li
Civil Engineering Dissertations - Archive
Today, 55% of the world’s population lives in urban area, a proportion that is expected to increase to 60% by 2050. Projections show that urbanization, the gradual shift in residence of the human population from rural to urban areas, combined with the overall growth of the world’s population could add another 2.5 billion people to urban areas by 2050. With growing opportunities, there are great challenges. One of the challenges that urban communities are facing is the increasing flood risks. In U.S., over the past decade, extreme storm events have wreaked havoc on many urban areas. Aging and inadequate infrastructure, …
Performance Study Of Link Slab Continuity In Prestressed Concrete Bridges,
2019
Louisiana State University and Agricultural and Mechanical College
Performance Study Of Link Slab Continuity In Prestressed Concrete Bridges, Marco Tulio Canales Jr
LSU Doctoral Dissertations
Link slabs in bridges can be a cost-effective solution to increase the service life of bridge structures. The partial continuity condition in link slab bridges, however can be challenging to quantify. In this work link slab performance is studied by means of a parametric study, a long-term Structural Health Monitoring (SHM) System, and a detailed finite-element model.
The parametric study was conducted using mathematical and a two-dimensional (2D) finite element model. The study considers bridge design factors such as number of spans, span length, span length ratio, girder separation, and temperature settings, in conjunction with the corresponding girder and support …
The Influence Of Incorporation Of Mn On The Pitting Corrosion Performance Of Crfeconi High Entropy Alloy At Different Temperatures,
2019
Clemson University
The Influence Of Incorporation Of Mn On The Pitting Corrosion Performance Of Crfeconi High Entropy Alloy At Different Temperatures, H. Torbati-Sarraf, Mitra Shabani, Paul D. Jablonski, Garrett J. Pataky, A. Poursaee
Publications
The electrochemical behavior and susceptibility to pitting corrosion of CrFeCoNi and CrMnFeCoNi high entropy alloys were studied in a 0.1 M NaCl solution at temperatures ranging from 25 to 75 °C. Electrochemical measurements revealed that CrMnFeCoNi is more susceptible to oxide film breakdown and localized corrosion compared to CrFeCoNi. Post corrosion microscopic observations showed severe pitting corrosion for CrMnFeCoNi in higher temperatures compared to CrFeCoNi. Based on in-depth XPS profile measurements on the remaining oxide films, this behavior was attributed to the depletion of Cr in the oxide film and detrimental presence of Mn in the matrix solid solution of …
Elimination Of Empirical, Ineffective And Expensive Pg Plus Tests To Characterize Modified Binders,
2019
Arkansas State University
Elimination Of Empirical, Ineffective And Expensive Pg Plus Tests To Characterize Modified Binders, Zahid Hossain, Ashraf Elsayed, Mm Tariq Morshed, Mohammad Hassan
Publications
For characterizing the polymer modified binders, different state Departments of Transportation (DOTs) use different time consuming and empirical Performance Grade (PG) Plus test methods. Furthermore, the PG Plus tests are silent when asphalt binders are modified with chemicals such as polyphosphoric acid (PPA). But, the effects of the elastomeric or plastomeric polymer are not accurately identified through these conventional tests such as Elastic Recovery (ER) and tenacity. Thus, the main research goal of this study is to recommend alternative test method(s), which can possibly be pursued by using a commonly available device, a Dynamic Shear Rheometer (DSR). Three PG binders …
Use Of Rice Husk Ash (Rha) In Flowable Fill Concrete Mix Material,
2019
Arkansas State University
Use Of Rice Husk Ash (Rha) In Flowable Fill Concrete Mix Material, Zahid Hossain, Kazi Tamzidul Islam
Publications
In the way of finding sustainable development, the flowable fill is a relatively new construction technology. Flowable fill is a self-compacting material, which has been developed in recent years. Flowable fill has been used for different applications such as backfilling walls, sewer trenches, bridge abutments, conduit trenches, pile excavations, and retaining walls. This study examines the potential uses of Rice Husk Ash (RHA) as a sustainable cementitious material (SCM) in the preparation of flowable fill concrete. (RHA is an agricultural by-product of the rice milling process. This study has evaluated the usage of RHA in producing low strength and self-consolidating …
Self-Healing Concrete Using Encapsulated Bacterial Spores In A Simulated Hot Subtropical Climate,
2019
Louisiana State University
Self-Healing Concrete Using Encapsulated Bacterial Spores In A Simulated Hot Subtropical Climate, Marwa Hassan, Jose Milla, Tyson Rupnow, Ahsennur Soysal
Publications
Bacterial concrete has become one of the most promising self-healing alternatives due to its capability to seal crack widths through microbial induced calcite precipitation (MICP). In this study, two bacterial strains were embedded at varying dosages (by weight of cement) in concrete. Beam specimens were used to identify the maximum crack-sealing efficiency, while cylinder samples were used to determine their effects on the intrinsic mechanical properties, as well as its stiffness recovery over time after inducing damage. The concrete specimens were cured in wet-dry cycles to determine their feasibility in Region 6. The results showed that the specimen groups with …
Karst Sinkhole Detecting And Mapping Using Airborne Lidar,
2019
University of New Mexico
Karst Sinkhole Detecting And Mapping Using Airborne Lidar, Su Zhang, Shirley Baros, Susan Bogus
Publications
The focus of this study is to detect sinkhole hazards using airborne light detection and ranging (LiDAR) data. The premise is sinkholes, particularly those close to transportation infrastructure assets, could cause substantial damages to infrastructure assets, and therefore, being able to accurately and rapidly detect them is essential. However, it is expensive, time-consuming, labor-intensive, and unsafe to survey sinkholes using conventional ground observation methods. This research project was focused on developing accurate and rapid airborne LiDAR-based sinkhole detection and mapping methods, and transfer the technologies to transportation engineers for implementation and workforce development. The project team also identified best practices …
Decision-Making Tool For Road Preventive Maintenance Using Vehicle Vibration Data,
2019
Texas A&M University
Decision-Making Tool For Road Preventive Maintenance Using Vehicle Vibration Data, Changbum Ahn, Chao Wang, Jing Du
Publications
Automated and timely road pavement damage inspection is critical to the preventive maintenance and the long-term sustainability and resilience of roads in Region 6. Current road inspection practices rely heavily on a manual process. Sensor-based methods (e.g., LiDAR scanning) are promising but can be too expensive for a wider adoption. This study employs a crowdsourcing approach of using the vibration patterns of regular vehicles in inferring specific types of road damages. A cloud-based smart phone app and system was developed to collect real-time vehicle vibrations, location data, and road damage images for training the detection model. However, there is a …
Strategies For Prioritizing Needs For Accelerated Construction After Hazard Events,
2019
University of New Mexico
Strategies For Prioritizing Needs For Accelerated Construction After Hazard Events, Fernando Moreu, Chao Wang, Xinxing Yuan, Laleh Ghanbari, Claudia Garrido
Publications
There is a need for rapid and responsive infrastructure repair and construction after natural disaster events such as hurricanes, wildfires, and tornadoes. These natural disasters often shut down basic infrastructure systems, as experienced recently in several Region 6 states as well as in other states around the country. Accelerated construction practices are often used in these situations to speed up the traditional, and often slow, project delivery process. However, after a natural disaster, several and different types of transportation infrastructure components are in need of inspection, rehabilitation or reconstruction, and transportation agencies are challenged with the task of prioritizing these …
Augmented Reality Enhancing The Inspections Of Transportation Infrastructure: Research, Education, And Industry Implementation,
2019
University of New Mexico
Augmented Reality Enhancing The Inspections Of Transportation Infrastructure: Research, Education, And Industry Implementation, Fernando Moreu, Chris Lippitt, Dilendra Maharjan, Marlon Aguero, Xinxing Yuan
Publications
Transportation infrastructure needs continuous monitoring that is conducted by field inspectors regularly in the field. Currently, infrastructure inspectors climb, measure, and photograph structures annually to inform repair needs and prioritize decisions. In order to promote and accelerate early learner's expertise in decision-making capabilities during infrastructure inspections, this research project developed various software applications using augmented reality (AR) as an inspection tool for bridges and bridge management, more specifically. By objectively quantifying infrastructure field inspections, inspectors can make more accurate field assessments and managers can make better-informed decisions. This project collaborated with stakeholders, national laboratories, DOT agencies such as NCHRP and …
Workforce Development Symposiums For Uhpc,
2019
New Mexico State University
Workforce Development Symposiums For Uhpc, Brad Weldon, Craig Newtson, Grace Mcmurry, Leticia Davila
Publications
Ultra-high performance concrete (UHPC) is a cementitious material with a dense microstructure that contributes to high compressive strengths as well as enhanced durability properties. UHPC also possesses significant post-cracking strength and ductility due to the addition of fibers. These characteristics produce a material that provides advantages over conventional concrete; however, high costs attributed to materials and production, lack of industry familiarity and knowledge, and the absence of standardized design procedures have impeded its widespread use. To help disseminate knowledge on UHPC, two workforce development symposiums on UHPC were held in Las Cruces, New Mexico. The symposiums consisted of presentations and …
Evaluation And Enhancement Of Carbon Sequestration Potential Of Existing Vegetation Along Roadsides,
2019
University of Texas at San Antonio
Evaluation And Enhancement Of Carbon Sequestration Potential Of Existing Vegetation Along Roadsides, Vikram Kapoor, Jeffrey Hutchinson, Samer Dessouky
Publications
The objectives of this study were to evaluate the vegetative composition and carbon sequestration potential of vegetation along a major roadway in Texas. Soil and vegetation were evaluated along IH-35 within Bexar County for composition and carbon content. Three 20 m transects were placed at each site and percent vegetative cover was estimated and above ground plant biomass, and soil was collected from three 0.25 m2 subplots along each transect. Plant and soil samples were analyzed for carbon content. Two non-native grasses, bermudagrass and King Ranch bluestem, were the dominant cover at all sites accounting for > 90% coverage at several …
Development Of Metals Corrosion Maps Of Arkansas And Maintenance Of Cross-Drains,
2019
Arkansas State University
Development Of Metals Corrosion Maps Of Arkansas And Maintenance Of Cross-Drains, Zahid Hossain, Ashraf Elsayed, Mdariful Hasan
Publications
Corrosion potential of metallic structures in alluvial soils is governed by chemical and electromagnetic properties of the soils. Geotechnical engineers are generally more concerned about different types of soils and their physical and mechanical properties than the chemical aspects. The main objective of this study is to analyze the geotechnical, electrochemical and electromagnetic properties of soils in Arkansas. Important parameters (e.g., soil resistivity) related to corrosion potential of metal culverts have been predicted through neural network (NN) models. The developed NN models have been trained and verified by using laboratory test results of soil samples collected from Arkansas Department of …
Assessing The Impacts Of Super Storm Flooding In The Transportation Infrastructure – Case Study: San Antonio, Texas,
2019
University of Texas at San Antonio
Assessing The Impacts Of Super Storm Flooding In The Transportation Infrastructure – Case Study: San Antonio, Texas, Marcio Giacomoni, Francisco Olivera, Cesar Do Lago
Publications
Flooding are likely to increase worldwide due to climate change. Large storms, referred here as superstorms, defined as events with return period equal or larger than 100 years, can lead to an increase of property damages and loss of life. The ability to predict and plan for the impacts of superstorms on transportation infrastructure is key to mitigate future damages and losses. This study analyzed 51 combinations of future projections for representative concentration pathways (RCP) 4.5 and 8.5 scenarios, which were used to calculate future 1st and 3rd quartiles, median, minimum and maximum intensity-duration-frequency curves (IDF). A HEC-HMS and GSSHA …
Use Of Bagasse Ash As A Concrete Additive For Road Pavement Application,
2019
Louisiana State University
Use Of Bagasse Ash As A Concrete Additive For Road Pavement Application, Gabriel Arce, Marwa Hassan, Maria Gutierrez, Michele Barbato
Publications
The objective of this study was to evaluate the use of sugarcane bagasse ash (SCBA) as a partial replacement of cement in concrete for road pavement application. The study explored the pozzolanic activity of SCBA produced from three different processing methodologies (i.e., raw SCBA, controlled SCBA and post-processed SCBA). The experimental results revealed that SCBA produced by the controlled burning of sugarcane bagasse fiber (SBF) at 650°C and grinding (C-650), presented the maximum pozzolanic activity. However, this SCBA production process was deemed challenging for large-scale industrial application due to low SCBA yield (i.e., 3 to 6%). On the other hand, …
Developing Implementable Climatic Input Data And Moisture Boundary Conditions For Pavement Analysis And Design,
2019
Oklahoma State University
Developing Implementable Climatic Input Data And Moisture Boundary Conditions For Pavement Analysis And Design, Rifat Bulut, Amir Hossein Javid
Publications
The main objective of this study is to develop a practical and implementable numerical model for predicting the moisture (suction) regime within the pavement subgrade system. The research quality and uniformly-dispersed climate data over short distances from Oklahoma Mesonet and the Mitchell based moisture (suction) prediction methods establish the main background of the research study. The study involved numerical modeling and statistical analysis of climatic weather data. The proposed moisture variation model predicts the suction distribution throughout the soil subgrade by solving the diffusion equation and incorporates the measured suction from the Oklahoma Mesonet to estimate the diffusion coefficient. The …
