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Full-Text Articles in Civil and Environmental Engineering

Surrogate-Assisted Simulation-Optimization Framework For Groundwater Management In A Multi-Aquifer System, Melika Mani Nov 2023

Surrogate-Assisted Simulation-Optimization Framework For Groundwater Management In A Multi-Aquifer System, Melika Mani

LSU Master's Theses

Uncontrolled groundwater exploitation can lead to aquifer depletion, land subsidence, and saltwater intrusion. Effective groundwater management is challenging due to the intricate nature of subsurface hydrogeology and spatiotemporally variable pumping, especially in a multi-aquifer system. To ensure sustainable withdrawal, multi-objective optimization is an effective tool for balancing management goals and drawdown effects. However, running simulation-optimization using detailed groundwater models is computationally expensive, pushing decision-makers to decide based on limited scenarios. In this study, a hydrogeological framework was constructed for the Capital Area, Louisiana, allowing for individual assessment of each unit to better understand each aquifer's condition. Moreover, a surrogate-assisted simulation-optimization …


Integrated Tire Wear Buildup And Rainfall-Runoff Model To Simulate Tire Wear Particles In Stormwater, Matthew Dupasquier, Jaime Hernandez, Alondra Gonzalez, Cesar Aguirre, Walter M. Mcdonald Nov 2023

Integrated Tire Wear Buildup And Rainfall-Runoff Model To Simulate Tire Wear Particles In Stormwater, Matthew Dupasquier, Jaime Hernandez, Alondra Gonzalez, Cesar Aguirre, Walter M. Mcdonald

Civil and Environmental Engineering Faculty Research and Publications

This paper presents an approach to integrate tire wear buildup and rainfall-runoff models to simulate tire wear buildup on road surfaces and its subsequent transport in stormwater runoff events. To do so, a buildup model is presented based on vehicle kilometers traveled, vehicle type, vehicle speed, and road roughness within a watershed. This buildup model was integrated into an EPA SWMM model that simulated the runoff of tire wear particles in twelve watersheds in the San Francisco, CA bay area. Results demonstrate that tire wear particle buildup within the watersheds ranged between 0.4 and 0.51 (kg/km2) per hour. Applied to …


Analyzing Major Elements Of Crash Injury Severity Involving Priority-I Detriments Of Vision-Zero Plan, Muhammad Umer Farooq, Cole Madson, Aemal Khattak Nov 2023

Analyzing Major Elements Of Crash Injury Severity Involving Priority-I Detriments Of Vision-Zero Plan, Muhammad Umer Farooq, Cole Madson, Aemal Khattak

Mid-America Transportation Center: Final Reports and Technical Briefs

Road traffic crashes result in significant economic losses for individuals, their families, and entire nations. These losses stem from the expenses associated with injury treatment, as well as the productivity lost due to fatalities or disabilities caused by these injuries. The 2030 Agenda for Sustainable Development set an ambitious target of halving the global number of fatalities and injuries from road traffic crashes by 2020 and achieving zero deaths by 2030, commonly referred to as the 'Target Zero Plan.' The Target Zero Plan prioritizes traffic safety issues into three distinct levels. The three priority levels are determined based on the …


Compound Flooding In A Non-Stationary World: A Primer For Practice, Gerarda M. Shields, J. Rolf Olsen, Miguel Medina Jr., Jayantha Obeysekera, Poulomi Ganguli, Carlo Demichele, Gianfausto Salvadori, Mohammad Reza Najafi, Hamed Moftakhari, Ferdinand Diermanse, Amir Aghakouchak Nov 2023

Compound Flooding In A Non-Stationary World: A Primer For Practice, Gerarda M. Shields, J. Rolf Olsen, Miguel Medina Jr., Jayantha Obeysekera, Poulomi Ganguli, Carlo Demichele, Gianfausto Salvadori, Mohammad Reza Najafi, Hamed Moftakhari, Ferdinand Diermanse, Amir Aghakouchak

Publications and Research

Compound flooding conditions present a significant challenge for civil engineers in their pursuit to design for and maintain the integrity of a structure’s entire life cycle. Coupled with non-stationary processes due to a changing climate and land use change, risk is a moving target. Through the support of ASCE’s Task Committee on Compound Flooding, the Hydroclimatology Engineering Adaptation (HYDEA) sub-committee is developing a Manual of Practice (MOP) to provide a synthesis of available tools and methods of best practice for civil engineers designing for compound flooding conditions. This paper presents a primer for practicing civil engineers on this work. Hydrodynamic …


Exploring Statistical And Machine Learning-Based Missing Data Imputation Methods To Improve Crash Frequency Prediction Models For Highway-Rail Grade Crossings, Muhammad Umer Farooq, Aemal Khattak Nov 2023

Exploring Statistical And Machine Learning-Based Missing Data Imputation Methods To Improve Crash Frequency Prediction Models For Highway-Rail Grade Crossings, Muhammad Umer Farooq, Aemal Khattak

Mid-America Transportation Center: Final Reports and Technical Briefs

Highway-rail grade crossings (HRGCs) are critical spatial locations of transportation safety because crashes at HRGCs are often catastrophic, potentially causing several injuries and fatalities. Every year in the United States, a significant number of crashes occur at these crossings, prompting local and state organizations to engage in safety analysis and estimate crash frequency prediction models for resource allocation. These models provide valuable insights into safety and risk mitigation strategies for HRGCs. Furthermore, the estimation of these models is based on inventory details of HRGCs, and their quality is crucial for reliable crash predictions. However, many of these models exclude crossings …


Road Work Zone Safety: Investigating Injury Severity In Motor Vehicle Crashes Using Random Effects Multinomial Logit Model, Aemal Khattak, Muhammad Umer Farooq Nov 2023

Road Work Zone Safety: Investigating Injury Severity In Motor Vehicle Crashes Using Random Effects Multinomial Logit Model, Aemal Khattak, Muhammad Umer Farooq

Mid-America Transportation Center: Final Reports and Technical Briefs

Work zones serve the purpose of facilitating maintenance and rehabilitation activities on roadways. However, these areas can also present unforeseen conditions to drivers, including narrowed right-of-way, lane shifts, and traffic disruptions. These conditions frequently contribute to vehicular crashes within work zones, resulting in property damage, injuries, and even loss of life. This paper aims to highlight work zone related crash data insights and presents statistical estimates of significant determinants of injury severity by analyzing ten-year crash data (2008-2018) from Nebraska, USA. The examination of crash data helped in highlighting work zone attributes that are empirically associated with serious injury crashes …


Understanding And Modeling Drivers’ En-Route Diversion Behavior During Congestion, Mohammad Shapouri Nov 2023

Understanding And Modeling Drivers’ En-Route Diversion Behavior During Congestion, Mohammad Shapouri

LSU Doctoral Dissertations

In the field of transportation, traffic assignment models primarily have been used to forecast driver route preferences, translating their choices into traffic flow patterns across networks. These models are grounded in distinct behavioral theories and strive to explain how drivers navigate routes based on network features and personal tendencies. Using an aggregation approach, conventional traffic assignment models distribute demand among paths, considering utility and attractiveness. Despite their prevalent use in transportation planning and operations, the fundamental behavioral assumptions of these models have rarely been thoroughly explored. This gap is further compounded by their limited consideration of real-time adjustments and choices …


Compatibility Investigation Of Waste Plastics In Bitumen Via A Molecular Dynamics Method, Hui Yao, Xin Li, Hancheng Dan, Qingli Dai, Zhanping You Nov 2023

Compatibility Investigation Of Waste Plastics In Bitumen Via A Molecular Dynamics Method, Hui Yao, Xin Li, Hancheng Dan, Qingli Dai, Zhanping You

Michigan Tech Publications

The compatibility between waste plastic polymers and bitumen is the most challenging issue hindering the improvement of modified bitumen performance. The current practice of recycled waste plastics includes the use of polyvinyl chloride (PVC), polypropylene (PP), polyethylene (PE), etc. This study was designed to investigate the compatibility of different waste plastic polymers with bitumen binders by conducting molecular dynamics (MD) simulations at different temperatures. The molecular models of these materials were constructed in this study for the compatibility analysis, and they include the base bitumen, polymers (PVC, PP, and PE), polymer- bitumen blending systems. Using the output and related calculations …


Integrated Flood Risk Assessment Of Properties And Associated Population At County Scale For Nebraska, Usa, Shivendra Srivastava, Tirthankar Roy Nov 2023

Integrated Flood Risk Assessment Of Properties And Associated Population At County Scale For Nebraska, Usa, Shivendra Srivastava, Tirthankar Roy

Department of Civil and Environmental Engineering: Faculty Publications

Risk assessment of properties and associated population was conducted for the state of Nebraska, leveraging only open-source datasets. The flood risk framework consisted of interactions among drivers, i.e. hazard, exposure, vulnerability, and response, to assess the risks related to properties and associated populations. To quantify hazard on a county scale, we considered properties at risk of flooding based on a flood score (a higher score represents a greater chance of flooding). Exposure was quantified by considering population density at the county level. We quantified vulnerability under four categories: social, ecological, economic, and health. Response, a relatively newer component in flood …


Integrated Flood Risk Assessment Of Properties And Associated Population At County Scale For Nebraska, Usa, Shivendra Srivastava, Tirthankar Roy Nov 2023

Integrated Flood Risk Assessment Of Properties And Associated Population At County Scale For Nebraska, Usa, Shivendra Srivastava, Tirthankar Roy

Department of Civil and Environmental Engineering: Faculty Publications

Risk assessment of properties and associated population was conducted for the state of Nebraska, leveraging only open-source datasets. The flood risk framework consisted of interactions among drivers, i.e. hazard, exposure, vulnerability, and response, to assess the risks related to properties and associated populations. To quantify hazard on a county scale, we considered properties at risk of flooding based on a flood score (a higher score represents a greater chance of flooding). Exposure was quantified by considering population density at the county level. We quantified vulnerability under four categories: social, ecological, economic, and health. Response, a relatively newer component in flood …


Behavior Of Two-Span Continuous Gfrp-Reinforced Concrete Deep Beams, Mohamed Shokry Abouelsaoud Nov 2023

Behavior Of Two-Span Continuous Gfrp-Reinforced Concrete Deep Beams, Mohamed Shokry Abouelsaoud

Thesis/ Dissertation Defenses

Steel-reinforced concrete deep beams are structural elements characterized by their large depth-tospan ratio. They play a crucial role in supporting heavy loads and transferring them to columns or walls in bridges, high-rise buildings, and marine structures. Corrosion is a major concern in steel-reinforced concrete structures, which can significantly reduce their lifespan and undermine their structural integrity. By replacing steel bars with fiber reinforced polymer (FRP) bars, the corrosion resistance of reinforced concrete (RC) structures can be improved and prolong their longevity. However, FRP bars behave elastically up to failure and have lower modulus of elasticity compared to steel, which affects …


Application Of Text Mining Techniques To Identify Actual Wrong-Way Driving (Wwd) Crashes In Police Reports, Parisa Hosseini, Seyedalireza Khoshsirat, Mohammad Jalayer, Subasish Das Nov 2023

Application Of Text Mining Techniques To Identify Actual Wrong-Way Driving (Wwd) Crashes In Police Reports, Parisa Hosseini, Seyedalireza Khoshsirat, Mohammad Jalayer, Subasish Das

Henry M. Rowan College of Engineering Departmental Research

Wrong-way driving (WWD) has been a long-lasting issue for transportation agencies and law enforcement, since it causes pivotal threats to road users. Notwithstanding being rare, crashes occurring due to WWD are more severe than other types of crashes. In order to analyze WWD crashes, there is a need to obtain WWD incidents or crash data. However, it is time-consuming to identify actual WWD crashes from potential WWD crashes in large crash databases. It often involves large man-hours to review hardcopy of crash narratives in the police reports. Otherwise, it may cause an overestimation or underestimation of WWD crash frequencies. To …


Environmental Sustainability Of Small Wastewater Treatment Systems And Pathways For Improvement, Matthew James Thompson Nov 2023

Environmental Sustainability Of Small Wastewater Treatment Systems And Pathways For Improvement, Matthew James Thompson

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Wastewater treatment protects society and the environment by reducing pollutants generated from communities prior to discharge into local water bodies. Small water resource recovery facilities (WRRFs) represent the majority of centralized wastewater treatment systems, are resource intensive, and often lack resources needed to evaluate sustainability improvements. The goal of this dissertation was to identify primary sources and drivers of environmental impacts in small WRRFs and exploration of pathways to improve their environmental sustainability.

Case study data collected from small WRRFs in Nebraska was analyzed using environmental life cycle assessment (LCA) to quantify the environmental impact of facilities and existing opportunities. …


Durability Of Cfrp/Steel Bond In Natural Weather, Mastour Alsulami Nov 2023

Durability Of Cfrp/Steel Bond In Natural Weather, Mastour Alsulami

USF Tampa Graduate Theses and Dissertations

Fiber reinforced polymers (FRP) are increasingly being used for infrastructurestrengthening and repair of steel structures. Though there have been several durability studies, exposures used are not representative of outdoor service conditions. Fewer studies have explored the effect of changing outdoor conditions typical in infrastructure use. The goal of the research is addressing this gap by evaluating the performance of commercially available CFRP systems under natural weather characteristic of hot, humid tropical conditions mainly and cold weather secondary in three different locations.

Thirty CFRP/steel joint specimens were prepared in laboratory conditions and exposed to ambient temperature on the Engineering building roofs …


A Bridge Information Modeling (Brim) Framework For Inspection And Maintenance Intervention In Reinforced Concrete Bridges, Ahmed Gouda Mohamed Nov 2023

A Bridge Information Modeling (Brim) Framework For Inspection And Maintenance Intervention In Reinforced Concrete Bridges, Ahmed Gouda Mohamed

Civil Engineering

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A Bridge Information Modeling (BrIM) Framework for Inspection and Maintenance Intervention in Reinforced Concrete Bridges

by Ahmed Gouda Mohamed 1, Ahmed Khaled 2 and Ibrahim S. Abotaleb 3,* 1 Department of Civil Engineering, Construction Engineering and Management Programme, The British University in Egypt, El Sherouk City 11837, Egypt 2 Department of Civil Engineering, The British University in Egypt, El Sherouk City 11837, Egypt 3 Department of Construction Engineering, The American University in Cairo, Cairo 11835, Egypt * Author to whom correspondence should be addressed. Buildings 2023, 13(11), 2798; https://doi.org/10.3390/buildings13112798 Submission received: …


Optimizing The Dynamic Replacement Of Soft Soils With Sand Using A Fem Tools, Walid Salem A Elsiwi Nov 2023

Optimizing The Dynamic Replacement Of Soft Soils With Sand Using A Fem Tools, Walid Salem A Elsiwi

USF Tampa Graduate Theses and Dissertations

First a dynamic finite element methodology (FEM) was developed to simulate an entire dynamic replacement (DR) program of clay with sand involving multiple poundings. The main objective of this research was to employ FEM and geotechnical test data such as cone penetration test (CPT) data at the site to predict the maximum achievable sand column (SC) depth and the corresponding optimum levels of attributing parameters such as number and height of pounder drops. Another goal was to predict the pore pressure generated in clay due to pounding. A full-scale ground improvement project was used to guide the analytical process. Comparison …


Predictive Modelling Of Road Deterioration Using An Artificially Intelligent Bayesian Belief Networks Approach, Babitha Elizabeth Philip Nov 2023

Predictive Modelling Of Road Deterioration Using An Artificially Intelligent Bayesian Belief Networks Approach, Babitha Elizabeth Philip

Thesis/ Dissertation Defenses

The ability to predict road deterioration is the cornerstone for developing a reliable Pavement Management System (PMS) that optimizes pavement maintenance programs. Such prediction capacity becomes increasingly important, especially when highway agency funds are confined. This research focuses on the development of prediction models based on an artificial intelligence technique, Bayesian Belief Networks (BBN), that aid decision-makers in forecasting expected road distress curves on the lights of various (e.g., environmental, traffic, and road-specific) factors and maintenance decisions. The novelty of this research revolves around deploying BBNs which allow analysts to yield Markovian predictions of annual road deterioration based on incomplete …


Characterization And Structural Shear Behavior Of Recycled Aggregate Concrete Beams Reinforced With Basalt Fibers And Basalt Bars, Shahrukh Shoaib Ul Haq Nov 2023

Characterization And Structural Shear Behavior Of Recycled Aggregate Concrete Beams Reinforced With Basalt Fibers And Basalt Bars, Shahrukh Shoaib Ul Haq

Thesis/ Dissertation Defenses

Recycling construction waste material offers a sustainable solution to the problem of disposing of concrete construction and demolition waste. The use of basalt fibers (BF) and basalt fiber-reinforced polymer (BFRP) reinforcing bars in concrete structures made of recycled concrete aggregate (RCA) would prolong their service life and reduce the maintenance cost. This research aims to investigate the potential use of BF, RCA, and BFRP reinforcing bars to produce sustainable and steel-free structural concrete. The study consisted of material characterization testing, numerical simulation, and large-scale beam testing.
Material characterization tests were performed on normal-strength concrete (NSC) and high-strength concrete (HSC). The …


Interdependency Between Water And Road Infrastructures: Cases And Impacts, Shihab Uddin Nov 2023

Interdependency Between Water And Road Infrastructures: Cases And Impacts, Shihab Uddin

USF Tampa Graduate Theses and Dissertations

This dissertation studies the interdependency between road and water infrastructures and associated interdependency impact on these two critical infrastructure systems. Critical infrastructures and the interdependency among these infrastructures have gained much attention recently because of its growing complexity, importance, and vulnerability to natural and man-made threats. In response, researchers have spent significant effort to study these infrastructures individually as well as when they are interdependent to understand complex interdependency relationship and to figure out ways to make these infrastructures more reliable, robust, and resilient. However, water and road infrastructure systems have not been studied as vastly as other critical infrastructures …


Hydrological System And Water Balance Of Ungauged Crater Lakes Of The Northern Crater Highlands, Godwin Lucas Nov 2023

Hydrological System And Water Balance Of Ungauged Crater Lakes Of The Northern Crater Highlands, Godwin Lucas

Tanzania Journal of Engineering and Technology (TJET)

The study aimed to unveil the hydrological system and water balance of the ungauged crater lakes with major focus on the Emakati Lake which occupy 46% of the Empakaai Crater associated to the East African Rift Valley and form part of the Northern Crater Highlands. Water samples for analysis of NO3- , Cl- and stable isotopes (2H and 18O) were collected from the Emakat lake, springs of the inner, outer and the foot of the Empakaai Crater rims. A combination of satellite data such as digital elevation model (DEM), Climate Hazards Group Infrared Precipitation with Station data (CHIRPS), net shortwave …


A Bayesian Network-Based Methodology For Improved Bridge Load Rating And Asset Management, Jeffery Mark Roberts Nov 2023

A Bayesian Network-Based Methodology For Improved Bridge Load Rating And Asset Management, Jeffery Mark Roberts

Dissertations and Theses

From the day a new structure is made available for use, to the day that the structure is no longer able to fulfill an intended purpose, structural safety is a vital interest. Managing a portfolio of structures can be a difficult undertaking for an asset manager, particularly if different types of structures are being maintained. The goal is to manage assets in the most efficient manner which can be influenced by, at a minimum, safety and financial concerns.

A potential tool for an asset manager or owner is the use of Bayesian Networks (BNs). When a BN is used to …


Integrated Periphyton Biofilters In Marine Recirculating Aquaculture Systems, Adam N. Bell Nov 2023

Integrated Periphyton Biofilters In Marine Recirculating Aquaculture Systems, Adam N. Bell

USF Tampa Graduate Theses and Dissertations

Marine aquaculture is a growing industry that has the potential to reduce eutrophication, overfishing, and loss of biodiversity. Recirculating aquaculture systems (RAS) are a type of aquaculture system that decreases discharge, raises biological control, and conserves water; however, RAS are challenged due to high energy cost, low biodiversity, water quality control, and waste nutrients. Periphyton biofilters are a new technology that allows for feed production, water quality control, microbial diversity, and resource recovery in marine aquaculture systems. The overarching question that this dissertation investigates is, how can periphyton biofilters be integrated into RAS to address the challenges of modern sustainable …


Biological Seawater Desalination Using Green Algae And Cyanobacteria, Abdul Mannan Zafar Nov 2023

Biological Seawater Desalination Using Green Algae And Cyanobacteria, Abdul Mannan Zafar

Thesis/ Dissertation Defenses

Water shortage in many coastal parts of the world is reaching alarming situation, including the United Arab Emirates. Urbanization and rapid population growth are generating critical water demands with an increase in per capita consumption. Seawater is usually treated by membrane processes such as reverse osmosis (RO). However, this technology is energy intensive and generates excessive brine as a waste. The solution to this problem can be found in natural remediation techniques that can reduce salt concentration from seawater, such as halophytes. A salt-tolerant species can consume Na+ and Clions and increase cellular growth which is termed biological desalination or …


Evaluation Of Residual Flexural Behavior Of Corroded Fiber-Reinforced Super Workable Concrete Beams, Jingjie Wei, Nima Farzadnia, Alfred Addai-Nimoh, Kamal Khayat Nov 2023

Evaluation Of Residual Flexural Behavior Of Corroded Fiber-Reinforced Super Workable Concrete Beams, Jingjie Wei, Nima Farzadnia, Alfred Addai-Nimoh, Kamal Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This Study Investigates the Effect of Macro Synthetic Fiber (MSF) Volume and Crack Widths on Corrosion of the Reinforcing Bars and Residual Flexural Behavior of Fiber-Reinforced Super-Workable Concrete (FR-SWC) Beams Exposed to Accelerated Corrosion. FR-SWC Beams Prepared with 0, 0.33%, and 0.66% MSF Were Pre-Cracked at 0.2-, 0.4-, and 0.75-Mm Widths Before Corrosion Testing. the Controlled Crack Width Was Initiated in One Set of Beams that Were Then Unloaded. the Crack Width Was Maintained for Another Set of Beams during Corrosion Testing by Inserting a Shim. Test Results Showed that the Use of 0.33% and 0.66% MSF Reduced Crack Development …


Cement-Based Materials With Solid-Gel Phase Change Materials For Improving Energy Efficiency Of Building Envelope, Zhuo Liu, Jiang Du, Ryan Steere, Joshua P. Schlegel, Kamal Khayat, Weina Meng Nov 2023

Cement-Based Materials With Solid-Gel Phase Change Materials For Improving Energy Efficiency Of Building Envelope, Zhuo Liu, Jiang Du, Ryan Steere, Joshua P. Schlegel, Kamal Khayat, Weina Meng

Nuclear Engineering and Radiation Science Faculty Research & Creative Works

This paper evaluated the cement-based materials incorporated with novel solid-gel phase change materials (PCMs) for improving the energy efficiency of building envelopes. This novel PCM is form-stable, which will not leak as solid-liquid PCMs do and not need encapsulation, and it features high energy-storage capacity. Experimental results showed that the thermal properties of cement-based materials were improved as the increase of PCM content. A 30% replacement of sand by volume with PCM can increase the latent heat of the mixture from around 0 to 7 J/g and decrease the thermal conductivity of PCM mortar based on the generalized self-consistent (GSC) …


Permeable Concrete Barriers To Control Water Pollution: A Review, Rehab O. Abdel Rahman, Ahmed M. El-Kamash, Yung-Tse Hung Nov 2023

Permeable Concrete Barriers To Control Water Pollution: A Review, Rehab O. Abdel Rahman, Ahmed M. El-Kamash, Yung-Tse Hung

Civil and Environmental Engineering Faculty Publications

Permeable concrete is a class of materials that has long been tested and implemented to control water pollution. Its application in low-impact development practices has proved its efficiency in mitigating some of the impacts of urbanization on the environment, including urban heat islands, attenuation of flashfloods, and reduction of transportation-related noise. Additionally, several research efforts have been directed at the dissemination of these materials for controlling pollution via their use as permeable reactive barriers, as well as their use in the treatment of waste water and water purification. This work is focused on the potential use of these materials as …


Shallow‑Water Habitat In The Lower Columbia River Estuary: A Highly Altered System, Will Templeton, David A. Jay, Heida Diefenderfer, Stefan Talke Nov 2023

Shallow‑Water Habitat In The Lower Columbia River Estuary: A Highly Altered System, Will Templeton, David A. Jay, Heida Diefenderfer, Stefan Talke

Civil and Environmental Engineering Faculty Publications and Presentations

Decreases in shallow-water habitat area (SWHA) in the Lower Columbia River and Estuary (LCRE) have adversely affected salmonid populations. We investigate the causes by hindcasting SWHA from 1928 to 2004, system-wide, based on daily higher high water (HHW) and system hypsometry. Physics-based regression models are used to represent HHW along the system as a function of river inflow, tides, and coastal processes, and hypsometry is used to estimate the associated SWHA. Scenario modeling is employed to attribute SWHA losses to levees, flow regulation, diversion, navigational development, and climate-induced hydrologic change, for subsidence scenarios of up to 2 m, and for …


Effect Of Type And Quantity Of Inherent Alkali Cations On Alkali-Silica Reaction, Pengfei Ma, Jiaoli Li, Jincheng Bai, Ying Zhuo, Lingyu Chi, Yanping Zhu, Zhenhua Shi, Hongyan Ma, Genda Chen Nov 2023

Effect Of Type And Quantity Of Inherent Alkali Cations On Alkali-Silica Reaction, Pengfei Ma, Jiaoli Li, Jincheng Bai, Ying Zhuo, Lingyu Chi, Yanping Zhu, Zhenhua Shi, Hongyan Ma, Genda Chen

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In this study, the macroscopical expansion induced by alkali-silica reaction (ASR) and its corresponding ASR products are investigated using ordinary Portland cement (OPC) mortar specimens with a gradient of boosted alkalis. Experimental results show that the expansion increases with the concentration of inherent alkalis. Sodium-boosted samples expand approximately three times as much as potassium-boosted samples. ASR gels that are present in aggregate veins are calcium-free and amorphous; the atomic ratios of ASR gels are nearly independent of the type and quantity of alkali cations. Aggregate ASR gel exudation occurs in high (≥2.5 %) sodium cases and produces potential Na-shlykovite. Crystalline …


Implementation Of Experimental Static Recrystallization Of High Strength Steel Into Computational Simulation Of Multi-Pass Slab Hot Rolling, S. K. Dasari, S. Ganguly, A. Abutunis, K. Chandrashekhara, M. F. Buchely, S. N. Lekakh, R. J. O'Malley, T. Natarajan Nov 2023

Implementation Of Experimental Static Recrystallization Of High Strength Steel Into Computational Simulation Of Multi-Pass Slab Hot Rolling, S. K. Dasari, S. Ganguly, A. Abutunis, K. Chandrashekhara, M. F. Buchely, S. N. Lekakh, R. J. O'Malley, T. Natarajan

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Microstructural changes and softening due to static recrystallization have a critical influence on thermo-mechanical behavior of high strength steels during industrial multi-pass hot rolling. Numerical simulation using finite element analysis (FEA) can be used to accurately predict the softening behavior during the hot rolling process. Therefore, the implementation of an experimentally defined static recrystallization model into FEA is necessary to get realistic simulation prediction. in this study, the extent of softening during static recrystallization in Si and Mn alloyed high strength steel was measured using double hit tests. a Gleeble™ thermo-mechanical simulator was used to perform the double hit tests …


Transportation Components Of The City Of Bennet Comprehensive Plan And Downtown Economic Development Plan, Kyle Mclaughlin Nov 2023

Transportation Components Of The City Of Bennet Comprehensive Plan And Downtown Economic Development Plan, Kyle Mclaughlin

Community and Regional Planning Program: Theses

In partnership with the City of Bennet, the University of Nebraska, and Marvin Planning Consultants, this project assisted the creation of the City’s Comprehensive Plan and Downtown Economic Development Plan by creating a transportation focused report as a supplement to those plans. The project operates in six sections; Introduction and Overview, Evaluate the Present, Engage the Community, Recommendations, Strategies, and Policies, Implementation and Funding, and Monitoring and Evaluation. The project scope included existing conditions understanding, qualitative and quantitative transportation analysis, public engagement and stakeholder meetings, coordination with two plan creators, identifying transportation improvements, description of implementation steps, overview of available …