Engineering Commons^™

Enhanced Wind Velocity Imputation Near Building Structures Using Advanced Machine Learning Techniques, Istiak Ahammed, Sujeen Song, Gang Hu, Jinwoo An, Bubryur Kim

Civil Engineering Faculty Publications

The evaluation of instantaneous wind flow patterns nearest to building architecture is crucial to ensuring structural stability, architectural integrity, and pedestrian safety. Particle image velocimetry (PIV), a technique for studying fluid flow by tracing particles, provides accurate predictions of instantaneous wind velocities (IWV). However, PIV encounters challenges in specific regions due to laser light-based experimentation, leading to missing data. Consequently, investigating the wind circulation pattern around buildings becomes more challenging. Numerous ML techniques have been employed to impute missing wind velocities at random building locations with minimal structural impact. This paper focuses on addressing this concern by utilizing a machine …

Enhancing Civil Infrastructure Performance Through Lidar-Based Dynamic Monitoring And Phased-Construction Bridges, Khalid Hossam Alkady

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

This dissertation aims to enhance the performance and structural integrity of civil infrastructure systems through two primary goals. The first goal is to develop and rigorously validate end-to-end frameworks for full-field monitoring of the dynamic response of civil structures via Ground-based Lidar (GBL) scanners. GBL can be employed to sample point clouds at a high sampling rate for dynamic data collection, which addresses the limitations of using contact-based sensors in structural health monitoring (SHM) applications used for early-detection of structural damage.

The second goal of this dissertation concerns the challenges associated with constructing bridges in phases, so they can remain …

Increasing Drift Capacity Of Non-Ductile Concrete Shear Walls Through Confinement With Fiber-Reinforced Polymer Application, Andrew Duong, Sophia Maglabe, Sheyna Rongong

Architectural Engineering: Graduate Reports

The seismic response and laboratory testing of pre-1980s reinforced concrete (RC) shear walls commonly exhibit undesirable concrete crushing and rebar buckling in the wall end-zones leading to a flexural compressive failure. The lack of ductility of these walls is attributed to low reinforcement ratios and absence of special boundary elements (SBE) as required by modern design code. Thus, the authors are proposing a fiber reinforced polymer (FRP) retrofit method to provide confinement to the end-zones of pre-1980s walls equivalent to that of an SBE. Current industry applications of FRP have largely been for shear strengthening of RC beams, columns, and …

Assessing The Effect Of Material Properties On Full Depth Reclamation (Fdr) Mixtures Via Compressive Strength Characterization, Toluwanimi Ogundipe

Graduate Theses and Dissertations

Enormous amounts of money to replace all poorly maintained roads with brand new construction or with rehabilitation options like the mill and overlay which neglects the address of underlying pavement issues. To reduce the cost intensity of new construction of dilapidated pavements, state departments of transportation are seeking cost-effective techniques to rehabilitate roads. One of the techniques that have been explored and implemented by state DOTs is full-depth reclamation. Full depth reclamation (FDR) as a pavement rehabilitation technique is the reclaiming and recycling of an existing pavement with a predetermined amount of existing base layer. The combination of the reclaimed …

Controlling Expansion Behavior Through Curing And Mix Design For An Expansive, Rapid-Setting Bcsa Cement, Amanda Parolini Dutra

Graduate Theses and Dissertations

Cracking in concrete has been a concern for engineers because it reduces its durability and strength. Some of this cracking behavior is due to shrinkage, which occurs when the water in the concrete evaporates and causes a reduction in volume. Expansive cements were invented to counteract this shrinkage behavior. This research studies a new formulation of a standalone, fast-setting, fast-strength gain expansive BCSA cement. Since it is a new cement, a limited amount of literature is available about mixture design, strength properties, and how to obtain the desired level of expansion. This study then aims to fill some of these …

Determination Of The Internal Erosion Potential Of Bcsa Soil-Cement Using A Modified Hole Erosion Test System, Edgar Enrique Ortega De La Cruz

Graduate Theses and Dissertations

Levees play a fundamental role in preserving human lives and resources and are the key infrastructure protecting against flood events. In the United States, the levee system is extensive, but unfortunately many of the levees were either not engineered or have well exceeded their intended design life. This was evident after the Midwest floods of 2019, which resulted in the failure of multiple levees leading to costly losses and repairs. In addition, flood levels remained high for days at a time, making it imperative to find fast and effective repair methods. This thesis presents a study conducted at the University …

Paste Properties, Hardened Concrete Properties, And Mix Design Process For Magnesium Phosphate Cement, Rilye Dillard

Graduate Theses and Dissertations

Magnesium phosphate cement (MPC) is a rapid-setting alternative cement typically used as a quick repair material. MPC has gained popularity in recent years due to its ability to reduce CO2 emissions, its strong chemical resistance, and potential use in large scale applications. There is currently limited research on the properties of MPC when varying the proportions of its ingredients. Several hardened concrete properties were analyzed on concrete mixtures made with MPC. A mix design process for MPC concrete is proposed based on testing of 300 MPC paste mixtures and 115 MPC concrete mixtures. A standardized mix design process is imperative …

An Investigation Into The Effect Of Performance Engineered Mixture (Pem) Design On The Workability And Strength Of Concrete Pavement Mixtures, Alexander Cook

Graduate Theses and Dissertations

The Arkansas Department of Transportation (ARDOT) currently requires a minimum cement content of 564 pounds of cement per cubic yard of concrete. This minimum cement requirement can be reduced through the utilization of optimized gradation of aggregates within concrete mixtures as well as the addition of supplementary cementitious materials (SCMs) such as fly ash. The study presented in this paper aims to demonstrate how the use of the Tarantula Curve can be used to design concrete mixtures with reduced cement contents while maintaining sufficient workability for concrete mixtures to be used for slipform paving. Fresh workability was measured using the …

Life-Cycle Cost Analysis Of Fm4 Txdot Roadway Alternatives In Cleburne, Texas, Ethan A. Bright

2024 Fall Honors Capstone Projects - Archive

The Engineering senior design group proposed a three-span concrete bridge, merged lane intersection, and a single storm conduit system. The Honors contribution to this project was analyzing the design’s alternative’s life-cycle costs to compare the most economic design. The project’s cost consists of initial construction, maintenance, and decommission. Utilizing Texas Department of Transportation (TxDOT) bid code unit prices, each design alternative is calculated by multiplying each material amount by the unit price then summed. Although the parallel conduit system has a cheaper initial cost, it requires more maintenance during its lifetime, therefore the single conduit system was recommended. Notably, cost …

A Strategic Insight Into The Market For Carbon Management Capacity, Mahelet G. Fikru, Ting Shen, Jennifer Brodmann, Hongyan Ma

Economics Faculty Research & Creative Works

This study presents the market for carbon management capacity via carbon capture, utilization, and storage technologies, identifying demand and supply forces, as well as clarifying the potential impact of market and non-market-based shocks on technology developers versus adopters. The paper addresses a prevailing gap in market analysis, introducing a microeconomic framework and unique dataset to identify key players, market forces, and policy incentives shaping the carbon capture, utilization, and storage landscape. The analysis equips industry stakeholders, policymakers, and investors with valuable insights regarding (1) leaders in the design, development, and manufacture of carbon capture, utilization, and storage technologies (supply), (2) …

Fitting Quality Of Nmr Relaxation Data To Differentiate Asphalt Binders, Rebecca M. Herndon, Kevin Lai, Magdy Abdelrahman, Klaus Woelk

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Asphalt binder performance grades (PGs) are important metrics in designing pavements for effective transportation infrastructure. the PG system relies on the binder's stiffness and is determined through energy- and time-intensive physical testing. Physical properties, like stiffness, can also be determined by spin–lattice NMR relaxometry, a non-destructive chemical method. NMR relaxometry can quantify the molecular mobility of materials by determining relaxation times from exponential decays of excited nuclear magnetization. While relaxation times have been used to determine physical properties of materials, a quantitative relation to the PG grades of asphalt binder is yet to be established. in this study, T1 NMR …

Collision Hazard Prevention And Notification For Construction Worker Safety Using Audio Surveillance, Kehinde Elelu

All Dissertations

The construction industry faces significant safety challenges, with collision hazards ranking as the second highest cause of annual fatalities and injuries in the United States, as reported by the Occupational Safety and Health Administration (OSHA). Current collision detection methods predominantly rely on proximity technologies, which necessitate costly and complex installations on each construction equipment piece. Furthermore, auditory situational awareness declines among workers due to hearing loss and intricate construction noises, which further heightens collision risks. This research introduces an innovative, low-cost, audio-based collision prevention technology aimed at enhancing auditory situational awareness for construction workers exposed to high noise levels. The …

Sustainable And User-Driven Scope Development Framework For Engineering Design Services Of Transportation Infrastructure Projects, Ahmad Zaki Ghafari

All Dissertations

Rapid economic growth has led to a significant increase in transportation demands, exerting unprecedented pressure on infrastructure systems in the United States. State transportation agencies play a vital role in maintaining and developing transportation infrastructure networks within their regions. State transportation agencies face immense pressure from federal and state governments, elected officials, and the public to deliver projects efficiently and within budget. State transportation agencies rely on professional consultants for engineering design services. Engineering design services for transportation infrastructure projects are delayed due to incomplete inaccurate scope. For state Department of Transportation (DOTs), a streamlined scope development process is essential …

Deep Learning Vision-Based Bridge Inspection With Resource-Constrained Unmanned Aircraft Systems, Ji Young Lee

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

Bridge inspection is critical for ensuring structural integrity, extending the service life of infrastructure, and minimizing maintenance costs. As bridges age and endure increasing loads, regular inspections help detect early signs of wear, such as cracks or corrosion, that could impact safety and performance. However, traditional inspection methods are labor-intensive, requiring significant time, specialized equipment, and manual access to challenging areas, which can lead to costly disruptions. Additionally, reliance on human inspectors introduces subjectivity, with assessments varying by individual expertise. These factors highlight the inefficiencies and safety risks in current inspection practices, underscoring the need for more objective, efficient solutions. …

Comparative Analysis Of Design-Build And Design-Bid-Build Project Delivery Methods Through Cost, Schedule And Quality Performance For Warehousing And Storage Facilities, Vijaya Ravi Prasanth Reddi

All Theses

Storage facilities are essential for e-commerce operations, providing inventory, distribution, and delivery space. As per the Bureau of Labor Statistics, the number of warehousing and storage businesses in the United States increased from 15,152 in 2010 to 21,287 in 2024, showing continuous growth over the decade. Given the recent surge, there is a need to understand the performance of these facilities better. This study aims to contrast the measure of quantitative performance of design-build (DB) versus traditional design-bid-build (DBB) project delivery methods (PDM) based on cost, schedule, and quality metrics for storage facilities. This research conducted a literature review to …

Non-Contact Acoustic Emission Detection Of Rail Defects Using Air-Coupled Sensors, Lei Jia

UNLV Theses, Dissertations, Professional Papers, and Capstones

Rail defects, whether internal or external, present significant safety risks. Acoustic Emission (AE) technology has emerged as a promising technique for monitoring damage progression and detecting these rail defects. This project addresses this critical concern by testing air-coupled optical microphones for non-contact AE detection. The goal of this research is to investigate AE signal characteristics using both rail-mounted and vehicle-mounted methods, establishing the understanding of AE signals in relation to defects and their effectiveness in identifying them.

This research focused on investigating air-conduct sensors in the lab-controlled pencil lead break (PLB) test. The objective was to evaluate the propagation characteristics …

Real-Time Assessment Of Rebar Intervals Using A Computer Vision-Based Dvnet Model For Improved Structural Integrity, Bubryur Kim, Sri Preethaa K.R., Yuvaraj Natarajan, Danushkumar V., Jinwoo An, Dong-Eun Lee

Civil Engineering Faculty Publications

Structural durability is critical for building and civil engineering safety, wherein the arrangement and distribution of reinforcing bar (rebar) is crucial. Improperly aligned rebar impacts bearing capacity, whereas uniform spacing optimally distributes loads, reducing stress. We introduce a computer-vision based Deep Vision Net (DVNet) model for real-time evaluation of rebar placement. A customized dataset is prepared in an environmental setup and augmented to address overfitting issues. This research conducts a comparative analysis of the learning performance exhibited by the proposed DVNet model against several other pre-trained models, such as Mask-RCNN and YOLOv5. The proposed DVNet model is built on a …

Impacts Of Stream Bed Adjustment On Local Bridge Morphology At Highway 281, Molly G. Likins

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

Nebraska sand-bed rivers have long been a part of sediment transport studies and have been used in the development of numerous well-known empirical bedload equations. Some of these studies have shown how adjustments in streambed elevation led to changes in local stream morphology. The sand-bed rivers of Nebraska are highly susceptible to such changes due to their wide, shallow cross-sections and erodibility. The objective of our study is to synthesize a hydrodynamic model with high-resolution field data and improved methods of representing sediment transport to better predict both short and long-term channel adjustments for an aggraded sand-bed river.

The field …

Numerical Study On The Behavior Of Natural And Recycled Aggregate Concretes, Shahriar Mardpour

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

This thesis investigates the mechanical behavior of natural and recycled aggregate concretes (NAC and RAC) using a multi-phase numerical approach to predict performance. Growing interest in sustainable materials has led to using recycled concrete aggregates (RCA) to replace natural aggregates, creating Recycled Aggregate Concrete (RAC). Due to their different structural components, RAC and NAC exhibit varying mechanical properties, particularly in strength and durability.

This study validated tension and bending (flexural) test models by comparing numerical results with similar models from the literature. Following validation, a multi-phase approach modeled NAC and RAC for the bending (flexural) and tension tests, providing a …

Development And Evaluation Of Highly Thixotropic Uhpc Mixtures For Bridge Overlay Applications, Akbota Aitbayeva

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

Ultra-high-performance concrete (UHPC) is an advanced construction material renowned for its exceptional strength and durability. However, conventional UHPC is typically self-consolidating, making it unsuitable for bridge deck overlay applications due to challenges posed by potential surface slopes. UHPC overlay construction requires a highly thixotropic material that not only responds well to vibration but also maintains workability over an extended period and remains stable on sloped surfaces. Despite the complex rheological properties of highly thixotropic UHPC, limited testing methods are available to effectively assess the workability and rheology of overlay mixtures. To address this gap, the present study provides a comprehensive …

Exploring Variably Saturated Flow Formulations For Modflow: Implementing A Fully 3d Richards' Equation In Modflow 6, Sebastian Vazquez-Gasty

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

This thesis explores the implementation of a fully 3D Richards’ equation solution into MODFLOW 6 to solve for saturated/unsaturated flow. Currently, MODFLOW 6 has limited capability for solving unsaturated zone flow problems by using the Unsaturated Zone Flow (UZF) package, which neglects capillarity and assumes vertical 1-dimensional flow. Various formulations of the Richards’ equation were first evaluated for their strengths and weaknesses. Various numerical solution approaches to Richards’ equation were also studied to understand the robustness and efficiency of different approaches and to select one that would best fit into the MODFLOW 6 framework. The MODFLOW 6 framework was also …

Prediction Of Cost And Schedule Changes In Transportation Projects Through Historical Bid And Change Order Document Analysis – Using Oklahoma Dot Project Cases., Rabin Shrestha

UNLV Theses, Dissertations, Professional Papers, and Capstones

Construction bid documents encompass project specifications, drawings, schedules, and other critical details and are the foundation for project bidding and execution. Accurate bid documents are essential to ensure project bids are competitive, realistic, and aligned with requirements. However, bid documents are susceptible to risks from various sources. Failure to identify and rectify these risks can result in inaccurate cost estimates and higher bids. Therefore, identifying and resolving risks within bidding or contract documents are of utmost importance. While prior research has shed light on potential risk factors within the bid documents, a noticeable gap remains in the literature regarding identifying …

Accelerating Microbial-Induced Calcite Precipitation Treatment Protocols Using Calcium-Based Stabilizers Targeting Pavement Construction, Grant Goertzen

Boise State University Theses and Dissertations

The research, development, and implementation of sustainable and resilient infrastructure is a critical mission for all aspects of modern Civil Engineering. The engineering and construction sector accounts for 37% of all global greenhouse gas emissions, comprising the largest proportion of any industry (Kafu-Quvane et al. 2024). Typically comprising 100% of base and subbase layers, 90% of asphalt pavement, and 80% of concrete pavement, it takes approximately 38,000 tons of aggregate to construct a single-lane mile of interstate highway (Feuling 2024). This presents significant environmental challenges due to the negative impacts of quarrying and aggregate transportation such as habitat destruction, biodiversity …

Performance Of Geopolymer Concrete Incorporating Recycled Aggregates And Glass Fibers, Mohammed Abughali

Thesis/ Dissertation Defenses

This study aims to investigate the potential use of geopolymer concrete (GC) incorporating recycled concrete aggregates (RCA) and glass fibers (GF) as a sustainable alternative to traditional cement-based concrete. It comprehensively evaluated the impact of RCA and GF on the fresh, physical, mechanical, and durability properties. A blended precursor binder consisting of ground granulated blast furnace slag and fly ash was utilized. To mitigate the challenges associated with the brittle behavior and low crack resistance of GC, mainly when incorporating RCA, two types of GF were used. Type A had a length of 24 mm, while Type B exhibited a …

Integrated Sustainability Analysis Of A Shared Micro-Mobility System In University Campus: Life-Cycle Assessment And User Impact Study Of Electric Scooters, Md Afif Rahman Chowdhury

LSU Master's Theses

The objective of this study is to evaluate the environmental, economic, and social impacts of implementing e-scooter technology on the LSU campus. The study is structured into three main parts: (1) an environmental life-cycle assessment of e-scooters, (2) a comparative environmental and economic impact assessment of e-scooters, cars, and campus shuttle buses, and (3) a comprehensive survey of e-scooter users to assess their characteristics, satisfaction levels, and comfort while using e-scooters on the LSU campus.

To achieve the objectives of the study, a life-cycle assessment (LCA) was conducted to assess the environmental sustainability of e-scooters, encompassing all stages from raw …

Next Generation Permeable Pavement For Enhanced Durability And Functionality, S M Tanvir

LSU Master's Theses

Porous Asphalt Concrete (PAC), also known as Open-Graded Friction Course (OGFC), is known for its high permeability, which provides benefits such as enhanced rainwater drainage, improved skid resistance, and reduced hydroplaning risks. These characteristics are due to its high air void content, allowing water to flow through the pavement and reducing splash, spray, and noise compared to conventional asphalt mixes. However, this high air void content also contributes to durability concerns, such as raveling, stripping, and clogging, which can reduce service life and increase costs, making OGFC more expensive than conventional asphalt mixtures.

This research focuses on identifying the failure …

Geotechnical Characterization Of Saline Sabkha Soil Of Abu Dhabi, Uae, And Its Stabilization Using Steel Slag And Sodium Silicate, Ahmed Maher Abdulla

Thesis/ Dissertation Defenses

Saline sabkha soil is widely distributed across the Abu Dhabi coastal regions of the UAE. These soils are associated with geotechnical problems that principally emerge from the heterogeneous nature of the soil and its high soluble salt content. Upon exposure to fresh water, the soluble salt dissolves, resulting in loss of the bond that once cemented the soil particles. In addition, the volume occupied by the salt minerals becomes part of the voids between the particles. This process results in a weak and loose soil structure of lower bearing capacity that is ready to collapse upon being subjected to loads. …

Float: A Multi-Scale Flood Loss Assessment Tool Developed From Experimentally Derived Material Damage, Anna Katya Opel

Doctoral Dissertations

Current practice of flood loss prediction presents limitations in accurately predicting building flood losses at multiple scales. While whole-building estimates can more accurately predict high-level losses (i.e., large groups of buildings), a significant analysis error is revealed with small-scale (i.e., individual, or small groups of buildings) investigation. The novel approach of collecting experimental flood data to support damage estimation has provided sufficient evidence that current damage models can and do under or overestimate loss. This research has developed a multi-scale approach to assessing flood losses based on experimentally derived material damage. The methodology is stored and accessible in a multi-scale …

Integrating Gis And Ca-Markov Model To Study Urban Dynamics Of Salem, India In Terms Of Pattern, Intensity And Direction, Linda Theres B

Theses and Dissertations

Urban populations have grown substantially in the modern era and the information age as people seek better living prospects. Currently, more than half of the world's population resides in the cities. Such growth must be monitored to ensure that people enjoy the boons of urban spaces, not the banes. Recognising the significance of urban studies, several researchers have attempted to analyse and predict urban dynamics using remote sensing, Geographic Information Systems, and machine learning methods. However, certain limitations exist, especially in improving the CAMarkov model's prediction performance. In addition, studies have suggested that growth characteristics, such as pattern, intensity, and …

Unlocking Telecommuting Patterns Before, During, And After The Covid-19 Pandemic: An Explainable Ai-Driven Study, Adedolapo Ogungbire, Suman Kumar Mitra

Civil Engineering Faculty Publications and Presentations

The COVID-19 pandemic has instigated a global paradigm shift in employment practices, precipitating a widespread transition to telework. While past events had no long-lasting effect on the continued working conditions of the population, it is unclear what a prolonged need for telecommuting on such a nationwide scale would continue to have on the working population. This study uses an explainable artificial intelligence approach to investigate the changes in those telecommuting across three periods: i) pre-pandemic, ii) pandemic, and iii) post-pandemic periods. Machine learning methods, including decision trees, random forest, extreme gradient boost, naïve Bayes, and artificial neural networks, were developed …