Civil Engineering Commons^™

Size Effects In Additively Manufactured Inconel-718 Thin Elements And Cellular Structures, Reem Abdelkarim Abo Znemah

LSU Doctoral Dissertations

A current focus in the additive manufacturing (AM) research community is the production of complex shaped metallic parts and cellular structures. Many researchers went on analyzing and simulating these structures without considering the effect of the element thickness and heterogeneous printing parameters on the resulting material behavior. To advance the application of laser powder bed fusion (LPBF), an AM process, in producing Inconel718 (IN718) complex shaped parts and cellular structures, this study aimed to investigate the effect of thin-walled elements thickness on the mechanical characteristics of both the individual elements and overall cellular structure. A multiscale experimental evaluation of the …

Probabilistic Modeling Of North Atlantic Ocean Hurricane Spawn Considering Climate Change, Susmita Bhowmik, Weichiang Pang, Michael Stoner

Publications

Hurricanes are a significant natural hazard, which cause significant damage and financial losses in the coastal areas of the United States almost every year. For example, the devastating nature of North Atlantic Ocean (NAO) storms can easily be understood from the 2005 Hurricane Katrina, which was the most damaging NAO storm in modern history, causing more than 1,800 deaths and a financial loss of at least 161.3 billion USD. It has been found that the formations of hurricanes depend heavily on climate conditions, which implies a direct relationship between the changes in climate extremes and the occurrences of hurricanes or …

Characterizing Wind-Wave Flow Physics And Loading Effects On Power Transmission Systems And Offshore Wind Turbines, Tianqi Ma

LSU Doctoral Dissertations

Recent extreme hurricanes caused extensive damage to critical civil infrastructure. Accurate modeling of the extreme complex wind fields and coupled wind-wave fields is essential to quantify the single wind or combined wind-wave loading effects on the structures. This research aims to characterize wind and wind-wave flow physics to quantify the loading effect on power transmission systems and offshore wind turbines.

First, a microscale (∼km) high-fidelity high-resolution computational model is developed to simulate hurricane wind fields with detailed physics. The generated wind field is applied to analyze the structural response of a power transmission system. The proposed hurricane boundary layer (HBL) …

Exploration Of Shared Passenger Urban Air Mobility – Integrated Network Design, Operation Scheduling And System Configuration, Zhiqiang Wu

USF Tampa Graduate Theses and Dissertations

Urban air mobility (UAM) is an emerging concept proposed in recent years that uses electric vertical take-off and landing vehicles (eVTOLs). UAM is expected to offer an alternative way of transporting passengers and goods in urban areas with significantly improved mobility by making use of low-altitude airspace. Considering the high capital investment of eVTOLs and relative high fee of using UAM passenger service, a viable UAM format is shared passenger service. Such a service is usually station-based, i.e., with vertiport located in popular sites where potential passengers can access. To understand the viability of such use cases, the vertiport owners …

Uncovering The Spatio-Temporal Impact Of The Covid-19 Pandemic On Shared E-Scooter Usage: A Spatial Panel Model, Farzana Mehzabin Tuli, Arna Nishita Nithila, Suman Mitra

Civil Engineering Faculty Publications and Presentations

This study examines the spatio-temporal effects of the COVID-19 pandemic on shared e-scooter usage by leveraging two years (2019 and 2020) of daily shared micromobility data from Austin, Texas. We employed a series of random effects spatial-autoregressive model with a spatially autocorrelated error (SAC) to examine the differences and similarities in determinants of e-scooter usage during regular and pandemic periods and to identify factors contributing to the changes in e-scooter use during the Pandemic. Model results provided strong evidence of spatial autocorrelation in the e-scooter trip data and found a spatial negative spillover effect in the 2020 model. The key …

Improved Burned Area Mapping Using Monotemporal Landsat-9 Imagery And Convolutional Shift-Transformer, Seyd Teymoor Seydi, Mojtaba Sadegh

Civil Engineering Faculty Publications and Presentations

Satellite imagery, specifically Landsat, have been widely used for mapping and monitoring wildfire burned areas. The new Landsat-9 satellite – with higher radiometric resolution compared to its predecessors, and improved temporal resolution when combined with Landsat-8 (∼8 days) – enables a wide range of applications, particularly burned area mapping (BAM). We propose a novel deep learning BAM model that leverages the strengths of the convolutional layers for deep feature generation from Landsat-9 imagery and shift-transformer block for burned area classification. The performance of the model is evaluated in five large fire case studies across the globe. BAM results are also …

Load Effects Of Truck Platooning On Existing Bridges In Oregon, Patricia Oleson

Civil and Environmental Engineering Master's Project Reports

Truck Platooning (TP) involves managing multiple trucks closely together to reduce aerodynamic drag. While TP offers benefits such as fuel savings, emission reductions, and enhanced safety, it raises concerns for existing infrastructure. This study reviews literature on TP and conducts bridge analyses comparing representative truck platoon configurations allowed under Oregon law with current truck loadings. It also explores the effects of truck head spacing and bridge span lengths, utilizing the research results to calculate rating factors using real-world case studies. The objective is to identify truck platoon configurations that may exceed acceptable load levels for Oregon bridges. The findings will …

An Open-Source, Semisupervised Water End-Use Disaggregation And Classification Tool, Nour A. Attallah, Jeffery S. Horsburgh, Camilo J. Bastidas Pacheco

Outreach

Research Objective/Summary: Research on individual household water consumption is vital to water management and conservation approaches. Despite a significant number of papers published on end-use disaggregation tools, reproduction and further study of results on water-use behavior is difficult because the data and code are not easily accessible. In order to fulfill this need for open and reproducible tools, we present a new, semisupervised, non-intrusive water end-use disaggregation and classification tool.

Application Of Artificial Neural Network (Ann) In Development Of Prediction Models For Pavement Performance And Material Properties, Prashanta Kumar Acharjee

Civil Engineering Theses

This dissertation presents the development and application of Artificial Neural Network (ANN)- based prediction models for Dynamic Modulus (E*), Dynamic Shear Modulus (|Gb*|, Phase Angle (b), Soil-Water Characteristics Curve (SWCC) parameters, and International Roughness Index (IRI). The IRI prediction model considering climatic and traffic conditions of Texas with data from the Long-Term Pavement Performance (LTPP) database with R 2 = 0.92 can be utilized by Local transportation agencies. An E* prediction model with three neurons, using 7400 data points obtained from 346 mixtures with R2=0.82 can bypass the need for laboratory tests. ANN-based |Gb*| and b prediction models were also …

Mapping Ecotourism Potential In Bangladesh: The Integration Of An Analytical Hierarchy Algorithm And Geospatial Data, Muhallil Abtahee, Afra Anika Islam, Md. Nazmul Haque, Hasan Zonaed, Samiha Mahzabin Ritu, S. M. Imdadul Islam, Atiq Zaman

Civil Engineering Faculty Publications

The significance of ecotourism has been increasing due to its potential for biodiversity preservation, economic advancement, and the promotion of sustainability awareness. In this research, geospatial analysis and the Analytical Hierarchy Process (AHP) was employed to identify feasible ecotourism sites in Bangladesh. The study applied Geographical Information System–Remote Sensing (GIS-RS) parameters and weighted overlay techniques for selected ecotourism characteristics, such as natural attractiveness, topographic features, accessibility, proximity to facilities, and community characteristics. The study found that a significant proportion (around 44%) of Bangladesh’s land exhibits high potential for ecotourism. Cox’s Bazar, Chittagong, and Rangamati are particularly favorable ecotourism locations. However, …

Initial Investigation Of Using The Waste Rubber Tires As A New Sustainable Material For Electric Conductive Rigid Pavement, Islam Radwan

Theses and Dissertations

The accumulation of snow on roadway surfaces has the potential to result in deadly accidents and financial damage. Traditional de-icing procedures, which include the use of chemicals or salt and the use of heavy machinery, may have a negative effect on the environment and the structural integrity of highway infrastructure systems, and they are not sustainable at all. In addition, these methods are considered labor-intensive and dangerous, especially in crowded areas. The use of heated pavement systems (HPS), which can be in the form of hydronic (HHPS) or electrically conductive concrete (ECON), has gained popularity in recent years as a …

Cost-Effective Strengthening And Automated Inspection Of One-Way Precast Reinforced Concrete Flat Slab Bridges In South Carolina, Laxman Kc

Theses and Dissertations

In South Carolina, the South Carolina Department of Transportation (SCDOT) manages 90% of the state's inventory of 9,400 bridges built in the 1950s. With more than 30% of its bridges having been under-designed and experiencing decades of service deterioration, the implications for public safety, the economy, and the transportation system are significant. To prioritize safety and address these concerns, SCDOT is in the process of conducting thorough inspections of bridges, load ratings, and exploring cost-effective and practical methods to strengthen the bridges and reduce load postings. This study is a part of the multi-year research investigation supported by the SCDOT. …

Assessment And Development Of Collaboration Framework For Less-Than-Truckload Carriers, Bhavya Padmanabhan

Theses and Dissertations

The growth of e-commerce is changing consumer expectations for delivery services. Competition is making “faster and cheaper” a nonnegotiable part of success; hence, retailers are seeking carriers that can deliver with ever-shorter lead times and at the lowest possible cost. In this environment, large carriers have a competitive advantage due to their market power. For small-to-medium-sized less-than-truckload (LTL) carriers to stay in business, they must improve their efficiency and lower cost. A potential strategy to achieve these goals is to collaborate with other carriers. In collaborating, carriers would exchange and perform certain jobs for each other to lower their transportation …

Impact Of Dam Height And Grain Size Distribution On Breaching Of Non-Cohesive Dams Due To Overtopping, Heather O'Donal

Theses and Dissertations

The National Inventory of Dams reports 74,400 earthen dams in the United States in 2021, of these dams approximately 27% are considered at high or significant hazard risk, that is dam failure will cause widespread damage and loss of lives. The most frequent cause of dam failure is breaching caused by overtopping. Accurate predictions of breach evolution are thus crucial to determine flood hydrographs for the safety of communities and properties at risk. Laboratory experiments were conducted on non-cohesive, compacted embankments to understand the role of dam height and sediment grain size on breaching caused by overtopping. Dam heights varied …

A Systems Approach To Design And Plan Sustainable Antifragile Infrastructure Based On Aggregate Footprint And Satisfaction, Farboud Khatami

Theses and Dissertations

The concepts of robustness and sustainability in planning and design of water and energy infrastructures have been extensively explored in previous research, primarily focusing on system reliability, environmental considerations, and economic aspects. This study aims to broaden the understanding of these concepts by offering comprehensive frameworks that capture the essence of robustness and sustainability at two distinct levels.

The first level of investigation focuses on the performance of infrastructure networks during natural disasters. Traditionally, this has been addressed using reliability, resilience, and vulnerability metrics. However, these methods rely on static, deterministic, and non-stationary data, which is inadequate when dealing with …

Implementation Of A 3d Laser Profiler System Into A Non-Contacting Method For Rnt & Stress Measurements, Caio Neto Penna

Theses and Dissertations

Continuous welded rail (CWR) is susceptible to the development of internal forces in the rail due to thermal effects that can lead to track buckling. Railroads typically deal with the internal stresses in the rail through the inspection of the rail neutral temperature (RNT) which is the temperature at which the internal force is zero. The existing methods in the industry to measure RNT are contacting, destructive, disruptive to railroad operations, and ineffective. The proposed concept is a promising non-contacting, non-disruptive and reference-free technique to measure RNT and the stress state in the rail. The method is based on the …

Utrgv Edinburg Campus Two-Dimensional Flood Modeling For Development Of Flood Inundation Map, Roxana Tello

Theses and Dissertations

Severe flooding is a natural hazard worldwide, potentially subjecting people to life threatening situations and leaving infrastructure vulnerable to structural damage or complete destruction. The common threat of flooding poses constant challenges for state and local agencies in identifying flood risks and proposing the necessary mitigation improvements. Developing hydraulic models to predict the hydrological interactions and identify areas at risk is a beneficial tool for urban planning. The Lower Rio Grande Valley (LRGV) is a rapid growing region in South Texas along the border of Mexico and west of the Gulf of Mexico. The LRGV has historically suffered through various …

Impacts Of Land Use On Stormwater Runoff In The Lower Rio Grande Valley And Improving Long Term Municipal Stormwater Management Systems, Maria Vanessa Pruneda

Theses and Dissertations

Exponentially noticeable growth in population and land development in the Lower Rio Grande Valley has directly influenced growth in urbanization. Urbanization is the leading cause for lower pervious cover, and the increase in storm water runoff. The increase of storm water runoff leads to excess flooding areas and higher peak flows. The overflow flows freely and is exposed to contaminants, affecting the consumption and use factors. The changes of land use have a direct relationship with impervious cover limitations and individual site retentions. This study will assess the relationship between stormwater quantity and land use in the Lower Rio Grande …

Development Of Intensity Duration Frequency Curve Of The Lower Rio Grande Valley, Binaya Poudel

Theses and Dissertations

Section 1: This chapter incorporates extensive information about the concept of Intensity-Duration-Frequency (IDF) curves, their historical development and usage, specific focus on the Lower Rio Grande Valley, and the importance of using a comprehensive 32-year data set from 1990-2022 to develop these curves.

Section 2: This chapter provides detailed information about the rigorous comparison of the developed IDF curves with previous ones, where past IDF curves were developed using an empirical formula method. The research presented here employs the Gumbel distribution method, providing a fresh perspective and potentially more accurate predictions of future weather extremes.

Section 3: This chapter outlines …

Building Services Engineering July/August 2023

Building Services Engineering

No abstract provided.