Civil Engineering Commons^™

‘‘Domicilelessness’’ And Livelihoods In Urban Areas: Case Of Maasai In Dar Es Salaam, Tanzania, Ombeni Swai

Tanzania Journal of Engineering and Technology (TJET)

The study aimed at demonstrating Maasai migration into Dar es Salaam urban areas and their challenges in accessing accommodation. Methodologically, the study deployed secondary data analysis following a descriptive research design. Furthermore, this study was conducted through both qualitative and quantitative research approaches. The study was conducted from 2018 to 2022 of which a random sample of 100 (N=100) was targeted. The data was analyzed using the Statistical Package for Social Sciences (SPSS Version 16). Findings: The Maasai means of accommodation are divided into four main categories: completed houses (6%), under-construction sites (39%), halfway constructed and abandoned structures (31%), and …

Modeling The Influence Of Internal Factors On Vehicular Mobility Performance, Aziz Mdimi

Tanzania Journal of Engineering and Technology (TJET)

Traffic mobility is significantly influenced by road conditions and the internal factors governing vehicular performance. Internal factors play a crucial role in vehicular mobility, influencing vehicles operate and performance. While existing vehicular mobility models primarily address external factors, external factors such as governor, engine, gear train and differential unit remain underexplored. This study formulates a comprehensive model to address this gap, focusing on the internal components that affect vehicular mobility. The proposed model employs both analytical and numerical methods to derive transfer functions for these subsystems using Matrix Laboratory (MATLAB), aiming to capture the dynamic behavior of vehicles under various …

The Effects Of Corporate Culture On Firm Growth: Evidence From Tanzania’S Construction Firms, Fred P. Okangi

Tanzania Journal of Engineering and Technology (TJET)

Corporate culture is one of those important aspects that determine the growth of firms. This study investigates the effects of the different types of corporate culture on the growth of Tanzania’s local construction firms. A survey of 227 Tanzania’s construction firms was undertaken using semi-structured questionnaire. The data collected were quantitatively analysed using Stata 13.0 software. The study results indicate that only the hierarchy type of corporate culture positively and significantly impacts the growth of Tanzania’s construction firms. The other types of corporate culture, such as adhocracy, market, and clan had insignificant effects on the growth of the construction firms …

Erodibility Of Sand-Silt-Xanthan Gum Mixtures, Edwin Kotey

Theses and Dissertations

The high frequency of earthen embankment failure recorded during floods has led to the general rule that embankments should not be overtopped. This notwithstanding, overtopping cannot be entirely avoided particularly during extreme events, such as winter storms and hurricanes. Reducing soil erodibility is thus fundamental to prevent and control disasters caused by embankment failure. Recent studies have explored the use of environmentally friendly additives, such as biopolymers, to improve soil properties. Geotechnical tests have shown that biopolymers can effectively increase soil strength, but little is known about biopolymer-treated soil resistance to erosion by flowing water. Results of flume experiments to …

B-Spline Impulse Response Functions For Transient Ssi Analysis Of Pile Foundations, Kingsley C. Ozegbe

Theses and Dissertations

The advent and consequential advancements in geotechnical earthquake engineering has made soil-structural analysis (SSI) an important component in the analysis and design of earthquake resistant structures. The filtering effects of pile foundations which reduces the seismic demand on pile-supported superstructure when they are subjected to seismic waves have been investigated and confirmed by several researchers in the last 40 years. To this end, several methods of analyzing the effects of SSI have been developed over the years. From the simplified Winkler model to the more robust finite element method (FEM) and boundary element method (BEM), researchers and structural engineers alike …

Classifying Floor Accelerations For Gait Estimation And Detection, Jean Michel Franco Lozada

Theses and Dissertations

Structural vibrations are traditionally used to learn about structural systems, such as determining the dynamic characteristics of a structure and evaluating its structural performance under certain dynamic loads. Recently, researchers have proposed the use of structural vibrations to know more about the occupants of the structure in addition to the structure itself. One example of such would be to determine when a person falls, or to identify the location of a person walking in a building. Using structural vibrations to study occupants can be directly applicable to many fields, ranging from healthcare to security applications. One powerful use of structural …

Dynamic Response Evaluation Of Loose Gravelly Soils In Centrifuge Modeling Experiments, Siwadol Dejphumee

Theses and Dissertations

Dynamic behavior of gravelly soil has gained more attention in recent years as several case histories of liquefaction of gravelly soil have been reported. Liquefaction can cause failure of infrastructure, leading to economic damage and loss of life. Gravelly soil has unique characteristics and engineering benefits, providing a prevalent and versatile construction material for various infrastructure projects. Therefore, understanding of the gravelly soil behavior under seismic load is critical for assessing the resilience of infrastructure located in seismically active regions. To date, only a few experimental research studies have focused on the dynamic response of gravelly soil, and these studies …

Field Implementation Of A Stereo Vision System For Rnt And Stress Measurements In Cwr, Brittany Stinson

Theses and Dissertations

The use of Continuous Welded Rail (CWR) provides many advantages to the rail industry compared to the alternatively used jointed-track segments. However, one significant disadvantage is the development of thermal stresses longitudinally in the rail, which is not of concern when expansion joints are used. This is due to CWR’s inability to release thermal expansion in the absence of joints. The Rail Neutral Temperature (RNT) is the temperature at which the rail is in a stress-free state. A desired RNT is calculated based on local climate conditions and CWR installation practices are implemented to set the desired RNT at installation. …

Internet Of Things And Ensemble Learning-Based Mental And Physical Fatigue Monitoring For Smart Construction Sites, Bubryur Kim, Sri Preethaa K. R., Sujeen Song, R R. Lukacs, Jinwoo An, Zengshun Chen, Euijung An, Sungho Kim

Civil Engineering Faculty Publications

The construction industry substantially contributes to the economic growth of a country. However, it records a large number of workplace injuries and fatalities annually due to its hesitant adoption of automated safety monitoring systems. To address this critical concern, this study presents a real-time monitoring approach that uses the Internet of Things and ensemble learning. This study leverages wearable sensor technology, such as photoplethysmography and electroencephalography sensors, to continuously track the physiological parameters of construction workers. The sensor data is processed using an ensemble learning approach called the ChronoEnsemble Fatigue Analysis System (CEFAS), comprising deep autoregressive and temporal fusion transformer …

Coastal And Inland Flooding - From Advanced Hydrodynamics And Data-Driven Modeling To Multi-Variate Coastal Vulnerability Assessment, Ahad Hasan Tanim

Theses and Dissertations

Flood risks in coastal and inland areas have historically been underestimated and underpredicted, resulting in increased flood damage and loss of human life. Flood risk under climate change and sea level rise will disproportionately impact low-wealth and marginalized communities, as they are often located in areas with less flood protection and have limited resources to adapt to the impacts of flooding. The systematic workflow of the life cycle of FRM is frequently disengaged in the current state of flood hazard assessment with system vulnerability assessment. This research aims to improve the life cycle of FRM by incorporating flood observation, monitoring, …

Analysis Of Water Usage And Greenhouse Gas Emissions As Transition Fuel From Coal To Natural Gas In San Juan County, New Mexico, Tahereh Kookhaei

Civil Engineering ETDs

Abstract

Coal is a major contributor to various environmental issues, making the transition to alternative energy sources essential for reducing environmental impacts and combating climate change. San Juan County in New Mexico has historically depended on coal-fired power plants for producing electricity. However, due to environmental and economic pressures, there is a move to reassess energy strategies. This study explores the transition from coal to natural gas (NG) in San Juan County, with a focus on assessing changes in water usage and emissions (CO₂, NO_x, and SO₂) at the Four Corners (coal-fired) and Afton …

A Hybrid Model For Assessing Safety Implementation And Project Success In The Construction Industry, Aya Hassan, Ali Hassan

Civil Engineering

Construction projects are prone to accidents and injuries, necessitating a focus on implementing safety programs. However, the implementation of such programs is influenced by various factors. Developing countries often have poor safety performance in their building sectors, with limited research in this area. This study aimed to identify essential safety program activities (SPAs) specific to the building sector. Through a literature review and survey, 25 SPAs were identified and validated via a pilot survey involving building sector experts. A questionnaire survey was conducted with 105 participants from the construction industry and academia. They were then categorized into four interconnected measurements …

The Effectiveness Of Waste Tire Pyrolysis Oils (Wtpos) As Rejuvenating Agents For Asphalt Materials, Ahmed S. El-Ashwah, Magdy Abdelrahman

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The continuous increase in solid waste materials, such as waste tires, underscores the critical importance of recycling them to mitigate environmental impact and promote sustainable resource management. This research study evaluated the effectiveness of utilizing waste tire pyrolysis oils (WTPOs) as recycling agents for asphalt materials. The chemical composition and thermal behavior of WTPO were analyzed using Fourier transform infrared (FT-IR) spectroscopy and thermogravimetric analysis (TGA). Mechanically, the prepared WTPO binders were assessed by measuring dynamic viscosity and changes in high- and intermediate-temperature performance grades. Additionally, the cracking susceptibility of the binders was evaluated using the Glover-Rowe (G-R) parameter. The …

Batch And Placement Size Effects On The Setting Time Of Bcsa Cement Concrete, Micaiah Rivers

Graduate Theses and Dissertations

Belitic calcium sulfoaluminate cement (BCSA) is an alternative to portland cement which offers numerous benefits due to its rapid-setting behavior and sustainability properties. BCSA cement concrete has many potential applications, particularly for structural and transportation infrastructure repair. Due to the rapid-setting properties of BCSA cement, a comprehensive understanding of the setting process is critical for efficient and effective use of this material. The primary objective of this research was to determine the effects of mixture size on the setting time and temperature behavior of BCSA cement concrete, and to investigate the relationship between initial set time and workability. Using a …

An Investigation Of The Effect Of Performance Engineered Mixture (Pem) Design On Durability And Air Void Matrix Of Concrete Pavements, Jacob Ortlieb

Graduate Theses and Dissertations

Performance Engineered Mixture (PEM) design is a novel method of creating concrete pavement that is economical achieving desirable performance properties such as durability, strength, and workability. Performance-based design is critical for concrete pavements, so the fresh concrete can be placed without issue and the hardened concrete can withstand deterioration and environmental damage such as freezing and thawing. To achieve economical concrete, PEM utilizes tools such as the tarantula curve for aggregate grading, and the Super Air Meter (SAM) test, providing information regarding the air void matrix while the concrete is fresh. To achieve these properties with less cement will lead …

Development Of An Innovative Rapidly Constructible Bridge, Swikar N. Pyakurel

Graduate Theses and Dissertations

Rapidly deployable temporary bridges are critical for military operations in hostile environments. The research focuses on conceptualizing bridge solutions for MLC 40 loading and 30 feet span that can be operational within hours, require minimal personnel and equipment, and are compact for logistics. An extensive literature review covered historic deployable structures, retractable stadium roofs, structures in aerospace, permanent deployable bridges, current military bridges, innovative deck solutions, lightweight structural materials, and compliant mechanisms. The study then investigated bridge superstructures made of lightweight Aluminum 6061-T6 alloy utilizing tensegrity and prefabricated aluminum extruded decks to meet the criteria. Two concepts, expandable scissor truss …

Impact Of Equipment Type On Measured Particle Size Of Civil Engineering Materials, Tanner Turben

Graduate Theses and Dissertations

Particle size analysis (PSA) captures the size distribution of fine-grained or emulsified materials with particles generally smaller than 1000 microns. Asphalt emulsions and many other 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 and to develop a draft standard procedure for asphalt emulsion PSA. Asphalt emulsions, cementitious materials, sands, clays, and biological samples were selected to represent a …

Identifying Waterway Traffic Flow Patterns Using Modified Clustering, Shihao Pang

Graduate Theses and Dissertations

Efficient management of inland waterways is essential for the economic and operational efficiency of transportation networks. Characterization and prediction of waterway vessel traffic flow patterns by time of day are critical for optimizing planned disruptive events like maintenance activities. This study identifies and predicts inland waterway traffic flow patterns along the Lower Mississippi River (LMR) using a modified clustering approach. A five-year period of Automatic Identification System (AIS) data, which tracks vessel movements in real-time, is used for model development and evaluation. The model first segments the river into approximately one-mile-long traffic message channels (TMCs) to estimate vessel counts and …

Applying Uas Lidar For Developing Small Project Terrain Models, Ashraf Siddiqui

Graduate Theses and Dissertations

Unmanned aerial systems (UAS) LiDAR was used to collect survey data for small-area projects, particularly bridge replacement projects. The project aimed to compare UAS LiDAR data with conventional surveying methods. For the project, five bridge sites were selected for UAS LiDAR and conventional survey data collection, which include Lincoln Bridge 1 (East), Lincoln Bridge 2 (West), Humnoke, Frenchman’s Bayou, and Mountain Home. Data for each site was collected during the 2021–2022 winter. A DJI M600 Pro and Phoenix LiDAR Systems AL3-16 LiDAR unit were used for the UAS LiDAR measurements. The conventional survey equipment used included a global navigation satellite …

Real-Time Barge Detection Using Traffic Cameras And Deep Learning On Inland Waterways, Geoffery Eyram Agorku

Graduate Theses and Dissertations

Inland waterways are critical for freight movement, but limited means exist for monitoring their performance and usage by freight-carrying vessels, e.g., barges. While methods to track vessels, e.g., tug and tow boats, are publicly available through Automatic Identification Systems (AIS), ways to track freight tonnages and commodity flows carried on barges along these critical marine highways are non-existent, especially in real-time settings. This paper develops a method to detect barge traffic on inland waterways using existing traffic cameras with opportune viewing angles. Deep learning models, specifically, You Only Look Once (YOLO), Single Shot MultiBox Detector (SSD), and EfficientDet are employed. …