Civil Engineering Commons^™

A Comparative Analysis Of Complete Streets And Multimodal Transport Approaches: Implications For Sustainable Urban Mobility In Lincoln, And Global Contexts, Oliva Richard Kilyenyi

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

Movement of people and goods in urban areas through different modes of transportation including walking, cycling, public transit and by autos is termed as urban mobility. Urban mobility presents significant environmental, social, and economic challenges for cities worldwide as they grapple with the impacts of conventional transportation systems, particularly in North America context where car-centric planning approaches has dominated urban developments since 1950s. Car-centric dominance is 80% in North American Metropolitan areas (Manaugh et al., 2015). The impacts of these conventional systems include greenhouse gas emission emissions contributing approximately 24% of global carbon dioxide (CO₂) emissions, air pollution …

Occurrence Of Per And Polyfluoroalkyl Substances In Rural Wastewater Treatment Plants And Comparison To Large Treatments Plants, Madeleine Rauhauser

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

Per and polyfluoroalkyl substances (PFAS) are a class of compounds defined by their carbon – fluorine bonds, which are incredibly strong. The strength of this bond makes these compounds very useful industrially, they are used as waterproof and grease proof coatings, and as fire retardants. The same thing that makes them useful industrially makes them incredibly recalcitrant in the environment, it is difficult to destroy these compounds. PFAS are also suspected to cause health impacts in people, such as kidney cancer and low birth weights. Wastewater has been commonly identified as a contributor to the amount of PFAS in the …

Rapid Construction Of Short Gap Crossings Using Indigenous Timber, Jack Everett Hamburger

Graduate Theses and Dissertations

This thesis examines multiple design options for constructing short span crossings for the military using indigenous timbers. Using indigenous timbers allows for a significant reduction in resources that must be brought into a site for construction. Construction time is minimized by optimizing the steps to convert indigenous timber into structural members for use as timbers in a short gap crossing. A major objective during this thesis study was to examine approaches for maximizing timber strength for design purposes and reduce timber weight for handling purposes. Wood strength and wood weight are highly dependent on moisture content. Decreasing moisture content addresses …

Impact Of Equipment Type On Measured Particle Size Of Civil Engineering Materials, Tanner Turben, Tasnimul R. Ferdous, Andrew Braham, Wen Zhang

Civil Engineering Faculty Publications and Presentations

Particle size analysis (PSA) captures the size distribution of finely graded materials with particles generally smaller than 1000 microns. Many civil engineering materials do not leverage PSA for material specifications or acceptance despite the insight into material performance and quality gained through understanding the particle size. The objectives of this study are to compare PSA measurement principles by testing 13 civil engineering materials by laser diffraction, Coulter counter, and microscopy. Asphalt emulsions, cementitious materials, sands, clays, and biological samples were selected to represent a wide set of interests and shapes. It was found that between laser diffraction and Coulter counter …

Accident Data Analytics And Ai-Based Auditory Enhancement For Highway Construction Safety, Thinh Nguyen

All Dissertations

This research develops data-driven and AI-enhanced approaches to improve worker safety in highway construction environments. The study integrates advanced analytics and auditory signal enhancement to identify high-risk worker behaviors and improve real-time safety warnings. The work consists of three core studies. The first study applies Sequential Pattern Mining and Social Network Analysis to more than 1,000 construction accident reports to identify high-risk worker actions and their hidden sequential relationships with accident types and consequences. These insights reveal sector-specific risk patterns, supporting the creation of targeted, data-informed safety interventions. The second study introduces an AI-based auditory enhancement model built on a …

Piezoelectric Energy Harvesting From Roadways: Challenges, Advances, And Future Directions, Heba Mohamed Gaber, Mohamed Abdel-Raheem

Civil Engineering Faculty Publications

As the global demand for renewable energy intensifies, piezoelectric energy harvesting from roadways has emerged as a promising avenue for sustainable power generation. This systematic literature review analyzes 61 peer-reviewed studies to assess the feasibility, performance, and potential of integrating piezoelectric systems into roadway infrastructure. While technology faces challenges, such as high installation costs, limited energy output, and a scarcity of thorough economic evaluations, findings suggest it holds considerable promise as a supplementary renewable energy source. The review analyzes the operational characteristics and efficiencies of various piezoelectric transducers, identifies key factors influencing system performance, and evaluates recent technological advances. It …

Advancements In Sinkhole Remediation: Field Data-Driven Sinkhole Grout Volume Prediction Model Via Machine Learning-Based Regression Analysis, Bubryur Kim, Yuvaraj Natarajan, K. R. Sri Preethaa, V. Danushkumar, Ryan Shamet, Jiannan Chen, Rui Xie, Timothy Copeland, Boo Hyun Nam, Jinwoo An

Civil Engineering Faculty Publications

Sinkhole formation poses a significant geohazard in karst regions, where unpredictable subsurface erosion often necessitates costly grouting for stabilization. Accurate estimation of grout volume remains a persistent challenge due to spatial variability, site-specific conditions, and the limitations of traditional empirical methods. This study introduces a novel machine learning-based regression model for grout volume prediction that integrates cone penetration test (CPT)-derived Sinkhole Resistance Ratio (SRR) values, spatial correlations between CPT and grouting points (GPs), and field-recorded grout volumes from six sinkhole sites in Florida. Three data transformation methods, the Proximal Allocation Method (PAM), the Equitable Distribution Method (EDM), and the Threshold-based …

The Equity Implications Of Pecuniary Externalities On An Electric Grid, Charles Sims, Gasser G. Ali, J Scott Holladay, Tim Roberson, Chien-Fei Chen, Islam H. El-Haddad

Civil Engineering Faculty Publications

The adoption of rooftop photovoltaic (PV) systems can create upward pressure on retail electricity rates as utilities are forced to spread their fixed costs of generation and transmission across a smaller customer base. Since high-income households are more likely to purchase PV systems, low-income households may be disproportionately impacted by these rate increases. Using a novel combination of agent-based computational economic modeling and a choice experiment of rooftop solar adoption, we show how this pecuniary externality between low- and high-income customers increases low-income electricity bills by 10% in an area with some of the highest poverty rates in the United …

Calibration Of Low-Cost Pm2.5 Sensors Using Data Continuously Generated At A Reference Station In El Paso, Texas, Brenda Lizbeth Hernandez

Open Access Theses & Dissertations

Low-cost sensors (LCS) offer a cost-effective way to expand air-quality monitoring networks, but they require strong calibration methods to ensure reliable performance under changing environmental conditions. In this study, Clarity LCSs were co-located with a state reference monitor for 6 months to evaluate fixed-time (2-, 3-, 4-, and 6-week) and rolling (2- and 3-week) calibration approaches. A multivariate regression model using PM1, PM2.5, PM10, and relative humidity was used to generate calibration coefficients for a “base sensor.” Data from two additional sensors were normalized to the base unit using linear regression, and their calibration coefficients were applied across the network. …

Investigation Of Hot Mix Asphalt Aging Effect On Binder Performance, Zahra Mohajeri

Open Access Theses & Dissertations

Asphalt roads continuously experience physicochemical changes under the combined influence of oxygen, heat, ultraviolet (UV) radiation, and water. Oxidation increases molecular polarity and association, causes maltenes loss, and continues hardening the asphalt binder, reducing ductility, stress-relaxation capacity, and resistance to cracking (Petersen 1982; Colbert and You 2012). Because aging is a cumulative process beginning at plant production, accelerating during construction/compacting, and continuing in service, the laboratory tests and indices must capture the extent of short-and long-term aging to support performance-related specification and Balanced Mix Design (BMD) (AASHTO R30 2022; Kim et al. 2017). This chapter reviews: (i) laboratory and field-representative …

Development Of A Handy Tool For The Selection Of Urban Stormwater Best Management Practices, Aaron T. Kenny

Civil & Environmental Engineering Theses & Dissertations

The City of Norfolk, Virginia faces substantial stormwater management challenges due to shallow groundwater, tidal influence, dense urban development, and limited right-of-way. These constraints limit the applicability of many Best Management Practices (BMPs) and require the early identification of feasible practices before detailed hydrologic modeling. This thesis introduces a decision-support tool that quickly and systematically identifies and prioritizes BMPs that are both feasible and well-suited to Norfolk’s Municipal Separate Storm Sewer System (MS4) program, streamlining early-stage selection and saving time and resources.

The tool implements a two-stage methodology. First, feasibility gates are applied using catalog attributes derived from the Virginia …

Using Hydraulic And Hydrologic Modeling To Determine Scour At Toro Creek Under Climate Change Conditions, Gabriel E. Alaniz

Master's Theses

ABSTRACT

This study evaluates bridge scour at the Toro Creek crossing of Highway 1 in Morro Bay, California, under present conditions and future climate conditions with more frequent extreme rainfall events. California infrastructure is becoming increasingly vulnerable to extreme storm events and increased intense precipitation events brought by climate change. This analysis focuses on the calculation of scour for both the northbound and southbound spans. Highway 1 plays a vital role in California’s coastal transportation infrastructure by carrying more than 20,000 vehicles daily (Caltrans, 2017). In this thesis, a hydrological model (HEC-HMS) is used to simulate runoff under present-day and …

Building Services Engineering November/December 2025

Building Services Engineering

No abstract provided.

Evaluating Use Of Multiple Hydrologic Storage Indicators To Enhance Streamflow Forecasting, Reza Morovati

All Graduate Theses and Dissertations, Fall 2023 to Present

Accurate seasonal streamflow forecasts are essential for managing water resources in the western United States, where much of the water supply depends on snow accumulation and melt. Water managers, farmers, and communities rely on these forecasts to plan for water use, prepare for droughts, and protect the environment. However, traditional forecasting methods often do not fully use all the available information about how water is stored in the landscape, such as in snowpacks, soil moisture, and groundwater. This can limit the accuracy of predictions and make water management more difficult.

This study aimed to improve streamflow forecasts by explicitly including …

Experimental Determination Of Modulus Of Rupture For Concrete Masonry Beams And Implications For The Tms 402/602 Code, Shreedhar K C

All Theses

Currently, the experimental database for Modulus of Rupture (MOR) of masonry beams is limited, and current provisions in TMS 402/602-22 use the MOR values from wallette tests. The primary goal of this research is to experimentally determine the parameters that influence MOR. The secondary goal of this work is to compare the MOR values from beam and bond wrench tests obtained in this study with each other as well as with values published in the literature. The standard ASTM E518 test was used for determining MOR values for beams, and a modified approach to ASTM C1072 that nullifies the eccentricity …

Depth-Averaged Two-Dimensional Hydrodynamic Modeling In Headwater Channel And Floodplain Design., Jesse Dylan Robinson

Electronic Theses and Dissertations

In the channels and floodplains of inland waterways the hydrodynamic forces of floods destroy property and infrastructure, threaten lives, and damage aquatic habitat. Flood simulations using robust and efficient depth-averaged two-dimensional hydrodynamic models (2D models) can be interpreted to design effective solutions for areas vulnerable to damage. The reliable interpretation of 2D models for use in design is improved here through direct comparison of 2D model output to observed flood events at 6 headwater research sites. Instrumentation was used for model calibration and to define the surface hydrodynamics at sites with confined flows, wide and shallow flows, at vertical steps, …

Alkali-Silica Reactivity And Ionic Transport In Mortar With Hydrophobic Inclusions., Isaac Offei

Electronic Theses and Dissertations

Alkali-silica reaction (ASR) causes extensive damage to concrete infrastructure worldwide, with traditional mitigation strategies increasingly constrained by supplementary cementitious material (SCM) supply limitations. This dissertation investigates an innovative approach to ASR prevention through strategic application of hydrophobic materials to modify moisture and ionic transport pathways in cement mortars. The research employed a comprehensive three-objective experimental program using highly reactive aggregates and three hydrophobic materials: hexamethyldisilazane (HMDS)-treated fumed silica, silane-based emulsion, and silane-based crème. The first objective demonstrated the feasibility of hydrophobic aggregate surface modification, achieving 46% and 38% reductions in ASR expansion for washed and non-washed hydrophobic aggregates, respectively. Microstructural …

Modeling Flood Risks For Small-Scale Coastal Watershed Across Shared Socioeconomic Pathway Scenarios, Sebastian Loschner

Graduate Theses and Dissertations (2019 - present)

Coastal flooding, driven by the mixture of natural processes and human activities such as precipitation, waves, sea level rise, and urbanization, remains a growing concern. While recent flood-risk studies use IPCC's Shared Socioeconomic Pathways with climate projections to assess future flood exposure, smaller coastal watersheds, < 120,000 acres, remain insufficiently studied. Projected sea level rise is expected to intensify these impacts in smaller systems, potentially causing more severe flooding than reported for larger watersheds. To address this gap, this study used the SRH-2D model integrated with Aquaveo's Surface-water Modeling System to simulate flooding in the lower Fish River basin, Alabama. A coastal watershed sensitive to both riverine and tidal influences. Simulations tested different sea levels based on SSP scenarios corresponding to low, moderate, and high emissions for the years 2050 and 2100. Results indicate that the midcentury scenarios remained even in inundation extent and volume, between 9.9-10.4% compared to the 2020 baseline, the latter scenarios had a wider range in results of between 25.9-50.3% compared to the same baseline. Across scenarios, the most vulnerable and inundated areas of the smaller coastal watershed were the narrow points where upstream flow convene with downstream backwater. These findings highlight the need for futuristic location-specific flood mitigation strategies.

Rainfall-Runoff Modelling In An Indonesian Humid Tropical Area Using Satellite-Based Precipitation Products, Noordiah Helda

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

This dissertation explores three rainfall-runoff models in the humid tropical regions of Indonesia using satellite-based precipitation products (SBPPs) and develops integrated machine-learning modeling frameworks. Several ground-based observations from BMKG (Badan Meteorologi, Klimatologi, dan Geofisika (also known as the Indonesian Agency for Meteorology, Climatology, and Geophysics)) stations across Indonesia (133−165 stations) are compared and evaluated against satellite products, indicating that GPM performs well, with R-squared values ranging from 0.54 to 0.76 and correlation coefficients ranging from 0.45 to 0.69, respectively.

In the Martapura Watershed, South Kalimantan, due to a lack of observational discharge data, streamflow was generated using the FJ Mock …

Upcycling Carbide Slag Waste For Low-Temperature Co2 Sequestration: Direct Application And Adsorption After Chemical Alteration, Manisha Sukhraj Kothari

Thesis/ Dissertation Defenses

Excessive carbon dioxide (CO₂) emissions and large-scale industrial waste generation are the results of rapid industrialization and ever-increasing energy demand. The recent trend of repurposing waste materials for pollution prevention is a promising approach to address both these environmental challenges. One such industrial waste residue generated from acetylene gas production is called carbide slag (CS). Its high Ca(OH)₂ content presents a promising opportunity for its utilization in CO₂ sequestration. However, CS waste is primarily studied as a CaO source for the intensive Ca-looping process. Despite the great potential, the high temperature requirements of the Ca-looping process limit its industrial application. …