Engineering Commons^™

Exploring Opportunities And Challenges Of Adopting Exoskeletons And Exosuits In Construction: Identifying Facilitators, Barriers, And Potential Solutions To Those Barriers, Dilruba Mahmud

Graduate Theses, Dissertations, and Problem Reports (ETD)

Exoskeletons and exosuits (collectively termed as EXOs) have the potential to reduce the risk of work-related musculoskeletal disorders (WMSDs) by protecting workers from exertion and muscle fatigue due to physically demanding, repetitive, and prolonged work in construction workplaces. However, the use of EXOs in construction is in its infancy, and much knowledge for driving acceptance, adoption, and application of this technology is still lacking. This paper aims to identify the potential facilitators and barriers to adopting EXOs in the construction industry, along with potential solutions to those identified barriers to fostering the adoption of EXOs in construction workplaces through a …

Evaluations Of Frp Composite Coupons Under Impact And Puncture, Lekhnath Bhandari

Graduate Theses, Dissertations, and Problem Reports (ETD)

Evaluations of FRP Composite Coupons Under Impact and Puncture

Lekhnath Bhandari

Railroad tank cars are the main mode of transportation for carrying flammable liquids and other hazardous materials, in any mode of ground transportation system. These tank cars, if punctured during derailments may explode releasing large amounts of hazardous materials and posing serious threats to human life and leading to economic losses. To minimize such catastrophes, in 2015, United States Department of Transportation (USDOT) proposed to improve the thermal and puncture performances of these tank cars and introduced two new design specifications: DOT-117 and DOT-117R. Tank cars with 9/16 inches …

Predictions Of The Dynamic Complex Modulus Of Non-Conventional Asphalt Concrete Using Machine Learning Techniques, Annie Benson

College of Graduate Studies: Theses & Dissertations

The complex dynamic modulus (|E*|) is a characterization property that defines the stiffness of an asphalt mixture. The dynamic modulus can be found through lab testing or predictions. Since lab testing can be time-consuming and expensive, the prediction method can be used as an alternative method. While a statistical method has been traditionally used for the |E*| prediction such as the Witczak’s predictive equations, machine learning (ML) is recently emerging as an alternative way that |E*| predictions can be made. This research attempted to predict the |E*| using several ML techniques including linear regression, support vector machines (SVM), decision trees, …

Environmental Controls Of Greenhouse Fluxes In Freshwater Wetlands Across The Globe, Samira Jahan

Graduate Theses, Dissertations, and Problem Reports (ETD)

Freshwater wetlands can contribute significantly to the global carbon budget as a net source or sink of the major greenhouse gas (GHG) fluxes such as carbon dioxide (FCO₂) and methane (FCH₄). The amount of GHG fluxes in the freshwater wetlands is highly variable and depends on a range of environmental drivers. These wetlands are commonly hypothesized to be net sinks (i.e., burial) of FCO₂ and net sources (emission) of FCH₄ at the monthly to annual scales. Understanding the environmental controls on the wetland GHG fluxes is essential for an accurate estimation of the global …

Strengthening Of Damaged Structural Members With External Frp, Krishna Tulasi Gadde

Graduate Theses, Dissertations, and Problem Reports (ETD)

Fiber reinforced polymer (FRP) composites are excellent alternatives to traditional materials for civil infrastructure. Several researchers have worked on the application of FRP composites for construction, repair, and rehabilitation of structures. This research aims at evaluating the use of carbon, glass, basalt, and hybrid FRPs with epoxy and polyurethane resin systems for rehabilitation of damaged structural components. Following evaluations were carried out in this research: (i) tension testing of FRP coupons, (ii) compression testing of concrete cylinders with and without damaged sections/FRP reinforcements, (iii) flexural testing of external-FRP reinforced RC beams with and without damages, (iv) pull-off tests on FRP …

A Computer Vision-Based Method For Tack Coat Coverage Inspection Using Drone-Collected Images, Aida Da Silva

Graduate Theses, Dissertations, and Problem Reports (ETD)

Tack coat is a thin asphalt applied between the existing surface and asphalt overlay during road rehabilitation. The uniformity of tack coat coverage plays a vital role in providing adhesive bonding between the two layers in the pavement structures. To ensure tack coat uniformity, the current practice primarily relies on manual inspection during construction by field experts. This process is time-consuming and tedious, and the results can be subjective and error-prone. Drones have emerged as a non-destructive sensing technology in the construction industry for many inspection practices. Unlike other non-destructive inspection technologies, drones offer benefits ranging from accelerating data collection …

Visual Sensing For Comprehensive Granular Traffic Data Collection In Support Of Intelligent Transportation Applications, Linjun Lu

Graduate Theses, Dissertations, and Problem Reports (ETD)

Comprehensive granular traffic data collection has been identified as one of the most essential tasks in the development of intelligent transportation systems (ITS). With the recent advances in electro-optical sensors and computational capacities, machine vision is regarded as cost-efficient for traffic data collection. However, the existing vision-based methods are only applicable for collecting limited types of traffic data, and a unified method allowing for comprehensive traffic data collection is still missing in the existing literature. Moreover, there are still challenges that exist for the use of the existing vision-based methods in real settings, including low accuracy and compromised applicability due …

Investigating The Change In Pavement Cracking Data Due To Automated Data Collection Methods, Faisal Quibria Chowdhury

Graduate Theses, Dissertations, and Problem Reports (ETD)

Data collection on pavement surface cracks is crucial for the state Departments of Transportation (DOTs) to make informed decisions on maintenance, repair, and rehabilitation (MR&R) activities. The collected cracking data is translated into a pavement performance indicator to assess the condition of pavement sections and identify MR&R needs based on predetermined threshold values set by the state DOTs. State DOTs have transitioned from manual to automated data collection as automation offers many advantages over manual data collection, such as improved data collection rates, efficiency, cost reduction, and safety. As the state DOTs have integrated automated data into the pavement performance …

Study Of Capillary Channel Fiber Augmented Geobags For Accelerated Dewatering Of High Moisture Content Fine-Grained Acid Mine Drainage Precipitate, Luke William Daugherty

Graduate Theses, Dissertations, and Problem Reports (ETD)

The objective of this study was to investigate techniques to accelerate filtration and dewatering of Acid Mine Drainage precipitate using geobags augmented with Capillary Chanel Fibers and internal lateral drainage structures. Laboratory and field research investigated increasing the total solids retention of Acid Mine Drainage precipitate in geobag storage systems. Current geobag design and field application of treated AMD precipitate exhibits limited filtration and drainage efficiency due to the high moisture content (2500%) polymer amended AMD flocculated solids. Capillary channel fibers (CCFs) are geosynthetic yarns formed with microgrooves and set into bundled arrangements capable of wicking water, via capillary action, …

Concentrated Wastewater Treatment Using A Ferric Iron-Dosed Anaerobic Upflow Sludge Blanket Reactor For Recovery Of Phosphorus And Ammonium, Carley E. Shingleton

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study evaluated the performance of a novel, ferric iron-dosed anaerobic bioreactor to recover two separate nutrient products from concentrated wastewaters -- phosphorus as vivianite (Fe₃(PO₄)₂×8H₂O) and an ammonium-containing effluent with low organics. A bench-scale upflow anaerobic sludge blanket (UASB) reactor fed with a synthetic wastewater (458.0 mg/L total organic carbon, 282.7 mg/L ammonium, and 84.4 mg/L phosphate) was dosed with a ferric chloride solution at an org. C/Fe³⁺ molar ratio ~17.5 to facilitate organic carbon oxidation coupled to iron reduction. The reactor design allowed natural settling of vivianite to its …

Assessing Morphological Changes Of The Msimbazi River Using Satellite Images, Fides J. Izdori

Tanzania Journal of Engineering and Technology (TJET)

This study assessed historical morphology changes of the Msimbazi River in Dar es Salaam City, Tanzania, following heavy rainfall events using historical Google earth images. The erosion and sedimentation processes that cause morphological changes of a river are also associated with flooding within the river catchments. In this study, the bank-line movement, erosion and sedimentation areas and changes in river section width were analyzed under three-time periods: 2005- 2012, 2012- 2018, and 2018- 2020. Data shows that, the timing for floods coincides with the historical records for heavy rains. It was found that, area in the upper reaches of the …

Concrete Technology In A Rapidly Growing Urban Environment – The Case Of Dar Es Salaam City, John K. Makunza Jkm

Tanzania Journal of Engineering and Technology (TJET)

Concrete is a building material that is used in great quantities second only to our use of water. The ingredient materials of concrete include cement, fine and coarse aggregates plus a reasonable amount of water, and sometimes additives. The construction of various structures like, residential buildings, commercial buildings, hospitals, schools, bridges, etc., needs good quality concrete. Good modern technologies are needed by the construction industry in order to effectively construct buildings which are durable. A study has been done with the main objective of assessing the concrete technologies existing in rapid growing cities in Sub-Sahara Africa like Dar es Salaam, …

Development Of An Operational Satellite-Based Flood Monitoring Model For Tanzania, Andrew Kimati

Tanzania Journal of Engineering and Technology (TJET)

Timely information during water related disasters is of utmost importance for flood preparedness and risk reduction. However, the conventional ground-based photographic monitoring of flooded areas is an expensive and time-consuming exercise. Satellite remote sensing is a quick and affordable approach that can be used for concurrent floods detection at different scales. This is important as it facilitates timely information for emergency response to disaster management departments, even in scarcely instrumented catchments. This study presents a novel approach for flood tracking using satellite image remote sensing science to map flood affected areas immediately after occurrence of rainfall events. An open-source water …

Analysis Of Ore Hand-Crushed Size Distribution For Grinding Process In The Artisanal And Small-Scale Gold Mines Production: A Case Study Of Nholi Mine, Bahi District, Malugu Tembo

Tanzania Journal of Engineering and Technology (TJET)

(ASGM) employed numbers of people compared to large-scale mines. The ASGM has been played a crucial role in poverty alleviation and rural development, particularly in developing countries. The mined ore is crushed and ground for beneficiation of gold. The grinding process involved the size reduction of blasted materials to acquire minerals of interest. This paper presents the size distribution of hand-crushed for blasted materials using sieve analysis and digital image processing. The sieve test results for hand-crushed blasted material of three muck-piles were ranged between 17 mm and 36 mm that is equivalent to 20% and 80% passings respectively, with …

Deployment Of Inductive Loop Vehicle Traffic Counters Along Trunk Roads In Tanzania, Daudi Simbeye

Tanzania Journal of Engineering and Technology (TJET)

As Tanzania's population grows, there is a greater demand for efficient, effective, and strong road design, as well as a smooth transportation system with a balanced traffic management network architecture. To plan for maintenance and expansion of such a vast network, a credible data inventory and network condition must be established. The deployment of vehicle inductor loop counters along Tanzanian trunk roads is presented in this paper. At test sites, inductor loop sensors and control cards were used to capture vehicle traffic data, which was then wirelessly sent using GSM technology for vehicle classification verification and storage for future road …

Energy Assessment Of E-Motorcycles As A Clean Transport Mode For Passenger Mobility: A Case Of Ilala District, Dar Es Salaam, John Shirima

Tanzania Journal of Engineering and Technology (TJET)

Electric motorcycles or e-motorcycles is a clean mode of road transport that present a prominent solution toward decarbonizing cities. Despite of e-motorcycles being cleaner than gasoline ones, at the moment, there is missing information whether it is feasible to replace gasoline motorcycles with e-motorcycles used for business transport purposes. This paper, therefore, presents the results comparing energy usage when using e-motorcycles and when using the gasoline motorcycles. The energy demand for driving passengers using an e-motorcycle in the precarious routes originated from Gongo la Mboto bus stop to Segerea bus stop, Buguruni Malapa, Gerezani bus stop, Kivukoni bus stop, and …

A Chemical Study Of Archaeometallurgical Ceramics From Southwestern Tanzania, Edwinus Lyaya

Tanzania Journal of Engineering and Technology (TJET)

Archaeometallurgical ceramics, including furnaces, tuyères, and potteries, were required for successful pre-industrial iron smelting and refining. However, there are limited chemical studies on archaeometallurgical ceramics in Tanzania. This paper examined the nature of clay source in terms of refractoriness, determined whether there were multiple clay sources, and verified the refractoriness of the archaeometallurgical ceramics. An x-ray fluorescence (XRF) analytical technique and experimental re-firing of the archaeometallurgical ceramics were employed. The chemical data clustered in the mullite region on the Al2O3-SiO2-FeO ternary system indicate that iron smelters and refiners chose refractory clay sources for making archaeometallurgical ceramics. Small range and standard …

Characteristics Of Extreme Precipitation And Their Effect On Bean Yield In Rwanda, Paul Ts Limbu Sr

Tanzania Journal of Engineering and Technology (TJET)

This study examines the characteristics of extreme precipitation and its effect on bean yield in Rwanda from 1981 to 2017. Over the study area, two rainy seasons, March to May (MAM) and September to December (SOND), account for approximately 80% of total rainfall. The spatial distribution of rainfall over Rwanda revealed that the first three EOF modes of MAM rainfall vary by 72.72 percent over the study period, while the first three EOF modes of SOND rainfall vary by 57.48 percent. The spatial analysis of extreme precipitation reveals that during wet years, the majority of the country's western regions receive …

Assessing The Influence Of Overweight Axles On Rutting Lives In Flexible Pavements Using Parametric Survival Analysis, Ali Hatoum, Jamal Khatib, Firas Barraj, Adel Elkordi

BAU Journal - Science and Technology

The existence of rutting or permanent deformation on flexible pavement layers has always been a concern that negatively affects the performance of roads by reducing the lifespan of pavement structure and by posing a safety risk for vehicles over the road. Traffic overloading is one of the primary factors that accelerates the deterioration of flexible pavement. This study aims to determine the time to failure of the flexible pavement structures associated with rutting, to indicate the most significant factors affecting rutting, and to assess the influence of overweight axles on pavement rutting life using parametric survival analysis. The data used …

Damage Stability Study Of A 500 Dw Ro-Ro Ferry Vessel, Zulfaidah Ariany, Budhi Santoso, Sarwoko Sarwoko, Nauval Abdurrahman Prasetyo

Makara Journal of Technology

The development of the crossing transportation industry is currently increasing in the island areas. The use of Ro-Ro type ferry boats is extremely efficient in moving people, goods, and vehicles. The current research focuses on the damage stability of the 500 DWT Ro-Ro ferry, which aims to meet the needs of the Ro-Ro ferry in the archipelago area. The previously existing initial design of a barge hull with a main size Lpp = 40.15 m, B = 12 m, H = 3.2 m, and T = 2.15 m was used to analyze the damage stability condition further. First, the drawings …

Fire-Resistance Testing Procedures For Construction Elements—A Review, Shashikant Chaturvedi, Ajitanshu Vedrtnam, Maged A. Youssef, Martin T. Palou, Gonzalo Barluenga, Kishor Kalauni

Civil and Environmental Engineering Publications

Fire accidents are a significant risk to human life and civil infrastructure. As a countermeasure, the regulatory bodies of different countries have established standards for evaluating the performance of construction elements during fire exposure. ISO 834 is the globally accepted fire-resistance testing standard. Other standards include ASTM E119, BS 476, IS 3809, JIS A 1304, AS 1503, EN 1363, and GB/T 9978, which are utilized by the US, Britain, India, Japan, Australia, Europe, and China, respectively. This article presents a summary and comparison of the fire-resistance testing standards. In reality, standard tests for isolated structural members may not efficiently portray …

Energy Dissipation In A Sand Damper Under Cyclic Loading, Ehab Sabi

Civil and Environmental Engineering Theses and Dissertations

Various seismic and wind engineering designs and retrofit strategies have been in development to meet structures' proper and safe operation during earthquake and wind excitation. One such method is the addition of fluid and particle dampers, such as sand dampers, in an effort to reduce excessive and dangerous displacements of structures. The present study implements the discrete element method (DEM) to assess the performance of a pressurized sand damper (PSD) and characterize the dissipated energy under cyclic loading. The idea of a PSD is to exploit the increase in shearing resistance of sand under external pressure and the associated ability …

A Framework For Multi-Dimensional Assessment Of The Impacts Of Overweight Vehicle Operations And A Corridor-Level Case Study, Maria Alicia Chung Li

Lyles School of Civil Engineering Graduate Student Reports

Ground freight transportation is essential for the economy of any region. The efficient movement of goods from one location to another connects businesses with suppliers and customers, that enhances commerce and ultimately boosts the economy. The high volume of freight that has been transported on the nation’s highway network has allowed the trucking industry to provide enormous socio-economic benefits. Unfortunately, these benefits come with some costs associated with the operation of overweight (OW) trucks, such as accelerated deterioration of highway pavement and bridge assets, and passenger and freight traffic safety degradation. Thus, to manage safety risk, traffic mobility, and infrastructure …

Exploring The Use Of Piox System For Treatment Of Endocrine Disrupting Compounds, Alexander Pearson

Civil Engineering Theses

In this thesis, the Photon Initiated Oxidation (PIOx) system was investigated for its possible use in the treatment of Endocrine Disrupting Compounds (EDCs). It was theorized that the unique design of the system, namely the multiple wavelengths of UV light and the micronfoam would improve removal rates of the test contaminant when compared to other systems. 17β-estradiol was chosen as the test contaminant due to the compounds known sensitivity to ozone exposure. Two methods of testing were used, the first to test an idealized homogenous concentration (method one) and the second to mimic the sudden influx of contaminant that would …

Evaluation For Using Expended Bioelectrochemical Systems As Soil Amendments For Improved Corn Plant Growth And A Drought Resistant Soil., Jackson Lee Sauers

Theses and Dissertations

A long-held practice is to mix agricultural soil with a soil amendment to improve growing conditions in crops. A common soil amendment is biosolids produced from both municipal and dairy wastewater due to the macro- and micronutrients within it. Both the agricultural and wastewater industries are participating in the Circular Economy concept (CEC). Two experiments explored using expended bioelectrochemical systems (BES) that treated either synthetic dairy wastewater (DWW) or synthetic municipal wastewater (SWW) as soil amendments to improve corn plant growth when treated with three different nutrient treatments: 100%- 50%- and 0% Hoagland Nutrient Solutions. Biochar and used terracotta clay …

Behavior Of Completely Automated Evapotranspiration Estimation (Eemetric), Atiqullah Atif

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

Evapotranspiration (ET) is the second-largest component in the water balance equation, globally consuming 70% of the earth’s annual precipitation. Accurate and consistent estimation of ET is essential for ensuring water resources sustainability, proper management, planning, and regulations of water resources. Though a 100% accurate estimation of ET may not be feasible with the current technology, there are proven techniques that give us estimates of ET we can heavily rely on. Mapping Evapotranspiration at High Resolution with Internalized Calibration (METRIC) is a widely used surface energy balance model that produces relatively accurate ET maps utilizing remote sensing data and requires skilled …

Experimental And Numerical Study: Sheet Pile Abutment Systems For Water-Crossing Bridges, Hung Phi Van

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

Sheet piles are geotechnical-structural elements with interlocking edges together that are driven into the ground to deliver soil retention and excavation support. Steel sheet pile walls are widely used for retaining walls, riverbank protection, seawalls, cofferdams, etc. In Nebraska, sheet pile walls prevent scouring and protect backfill for bridge abutment systems. While sheet piling is not designed and applied to resist vertical load, several recent studies attempted to investigate whether sheet piles could be employed for axial load bearing. Many projects from Europe and some in the U.S. have utilized the axial load-bearing capacity of sheet piles in bridge abutment …

Stochastic Approach To Hydrological Dam Safety In The Framework Of The New Dam Safety Standards In Spain, Iván Gabriel-Martin, Francisco J. Caballero, Álvaro Sordo-Ward, Luis Garrote

Protections Conference

The approval of the Technical Safety Standards for dams and reservoirs in Spain in 2021 increased the hydrological safety requirements, being necessary to check if measures have to be implemented in dams designed according to the prior standards. Some of these dams have scarce instrumentation and lack of hydrometeorological data. This work proposes a simple but sounded fully-stochastic methodology for assessing the hydrological safety of dams within this situation, potentially applicable outside academia. The methodology has been applied to a case study based on a real dam, and compared the results obtained to those of the standard deterministic procedure. We …

Wirewall A Follow Up: Labratory And Field Measurements Of Wave Overtopping, Tim Pullen, Jenny Brown, Margaret Yelland, Robin Pascal, Richard Pinnell, Chris Cardwell, David Jones

Protections Conference

At the Protections 2018 conference, the WireWall wave overtopping research project was introduced. WireWall uses recent advances in high frequency capacitance wire technology that can measure overtopping data. Wave overtopping has now been measured in the laboratory and in the field using the WireWall system. Here we provide an update on the validation of the system in flume tests and results from the first field measurement campaign.

Before deployment in the field, an extensive set of tests were carried out in one of the 2D wave flumes at HR Wallingford. These tests simulated known wave conditions from a buoy near …

Methodology For Calculating The Response Of Porous Media For Evaluating Grass Response To Overtopping Loads, Myron Von Damme, Dennis Den Ouden-Van Der Horst

Protections Conference

Grass covers offer a level of erosion protection against hydrodynamic loads induced by overtopping waves. The development of an accurate failure criterion for grass covers has been hampered by the lack of understanding of how grass fails. Methods have been developed to predict the hydrodynamic loads that act on the levee surface and consequently are transmitted to the porous grass cover and subsoil. However, it is unknown how these hydrodynamic surface loads on the soil are distributed amongst the pore water pressures and effective stresses, thereby offering a significant challenge for engineers to simulate the transmission of stresses into the …