Engineering Commons^™

Assessment Of Anaerobic Co-Digestion Of High Strength Organic Feedstocks Diverted From Landfills, Sumaiya Sharmin

Electronic Theses and Dissertations

The increasing generation of high-strength organic wastes such as food waste and fats, oils, and grease (FOG) presents challenges for landfill capacity and waste management. Anaerobic co-digestion offers a sustainable alternative by converting these wastes into renewable energy and nutrient-rich digestate. This study evaluated the co-digestion performance of single fruit waste residuals and mixed food waste with wastewater sludge to identify substrate combinations that maximize methane production while maintaining process stability. Laboratory-scale batch experiments were conducted under mesophilic conditions using thickened waste activated sludge (TWAS) with varying proportions of food waste and co-substrates, including seaweed, aquatic weed, grease trap waste, …

Integrated Construction Risk Assessment Framework, Felix Delmonte

Mechanical and Civil Engineering Faculty Publications

An integrated risk assessment architecture for construction projects synthesizes data governance, BIM, Digital Twins, and hybrid analytics into a continuous feedback loop that links sensing, semantic modelling, probabilistic simulation, and organizational learning. The framework distinguishes aleatory from cognitive uncertainty and prescribes layered methods: Monte Carlo and Bayesian updating for measurable variability; fuzzy inference and consensus aggregation for linguistic and expert judgements; and graph-based discovery for dynamic cyber-physical topologies represented as time-varying graphs 𝐺𝑡. Governance primitives, aligned with ISO 19650, enforce provenance, interoperability, and staged readiness thresholds that prevent premature prescriptive outputs until model convergence criteria are met. BIM and GIS …

Theoretical Model To Predict The Flexural Response Of Concrete Beams Pre-Tensioned With Cfrp Rods Considering Cfrp Slippage Effects, Yasir Saeed, Karrar Al-Lami, Franz Rad

Civil and Environmental Engineering Faculty Publications and Presentations

The overwhelming costs of maintenance for reinforced concrete structures due to steel corrosion have motivated researchers to look for alternatives. One of the promising alternatives is Fiber Reinforced Polymer (FRP). Among FRP materials, Carbon FRP (CFRP) is the most attractive material for prestressed concrete members due to its high tensile strength and modulus of elasticity. Previous studies investigated the use of CFRP in prestressed concrete through experimental tests and theoretical analysis. However, there is a significant need for more experimental data to develop an accurate model that can accurately predict the behavior of CFRP prestressed concrete beams. In the current …

A Machine Learning Approach For Water Quality Assessment In The Lower Rio Grande Valley Watershed, Saika Nowshin Nowrin, Chu-Lin Cheng, Jungseok Ho, Jinwoo An, Fatemeh Nazari

Civil Engineering Faculty Publications

Water quality analysis plays an essential role in maintaining the health and sustainability of river ecosystems, especially in semi-arid regions like the Arroyo Colorado Watershed in South Texas. Since the river is a vital source of water supply for local communities, agriculture, and wildlife, it faces significant challenges and pollution from land use changes, climate variation, and agricultural runoff. Continuous monitoring and assessment of water quality parameters and their temporal variability are essential to ensure the drinking water supply and aquatic ecosystem health. However, comprehensive laboratory-based water quality investigations are often constrained by higher costs, logistical complexity, and limited manpower. …

Evaluation Of Microwave Treatment Of Pfos-Laden Granular Activated Carbon, Rachel Melo Fonseca

Electronic Theses and Dissertations

This study investigated the microwave treatment as a potential regeneration approach for PFOS-laden granular activated carbon (GAC). PFOS was used as a model legacy PFAS, and calcium was selected to examine how inorganic constituents may influence PFAS loading and fluorine behavior during treatment. Microwave temperature profiling showed that GAC temperatures increased with treatment time and power level, reaching approximately 400-950°C. Selected microwave conditions reduced PFOS-derived extractable organic fluorine (EOF), with apparent EOF reduction increasing from 65.5% after 1 min to 96.8% after 4 min. Calcium increased PFOS-derived EOF loading before microwave treatment but did not show a consistent effect on …

Comparative Analysis Of Strain-To-Velocity Conversion Methods For Active-Source Das Data And Collocated Nodal Stations, Prajwal Panthi, Brady R. Cox

Civil and Environmental Engineering Student Research

Distributed Acoustic Sensing (DAS) provides dense spatial measurements of the dynamic strain along fiber optic cables, offering high-resolution wave sensing for ground motion monitoring and subsurface imaging applications. However, DAS records the axial strain or strain rate, whereas traditional seismic and engineering ground motion equipment and derived metrics are based on particle displacement, velocity, or acceleration, necessitating reliable strain-to-velocity conversion methods. This study evaluates three widely used conversion approaches: the fk-rescaling, curvelet-based conversion, and slant-stack methods. These approaches are applied to a unique high-energy, near-field, active-source dataset collected at the Birds Landing Site in Sherman Island, California. The dataset includes …

Nutrient Enrichment Of Palm Oil Mill Effluent Digestate (Pomed) With Fish Amino Acid And Boiler Ash For Biofertilizer Production, Aryati Putri Maharani, Ziyaulhaq Umar, Shahrul Ismail, Zulkarnaini Zulkarnaini

Journal of Environmental Science and Sustainable Development

Palm oil mill effluent digestate (POMED) has potential as a biofertilizer. However, its application is limited by unbalanced macronutrient composition, particularly low nitrogen (N), phosphorus (P), and potassium (K). This study investigated a laboratory-scale nutrient enrichment strategy for POMED using fish amino acid (FAA) as an organic nitrogen source and boiler ash (BA) as a potassium source. Nitrogen content was determined using a CHNS– O analyzer, while phosphorus and potassium were analyzed using inductively coupled plasma (ICP). Fertilizer quality was evaluated based on the standards and industrial research institute of Malaysia (SIRIM) and Indonesian national standard (SNI 2803:2010). FAA and …

Straw As A Potential Vegetable Fibre Insulative Infill In Framed Constructions - Material Testing\Tnotereftnote1, Patrick Daly

Journal of Sustainable Construction Materials and Technologies

The construction sector faces increasing pressure to reduce embodied carbon and adopt circular material strategies, with bio-based materials offering a promising pathway. Straw-based insulation, particularly in loose-fill form, has gained traction in Europe, where several products have achieved certification under EAD 040138-01-1201. This study investigates the potential of Irish-processed straw chip as a bio-based insulative infill for framed construction by evaluating its material properties and thermal conductivity–density performance relative to European ETA-certified reference products. A programme of laboratory testing was undertaken on commercially available Irish straw samples, including material characterisation (moisture content, particle morphology, and dust content) and thermal conductivity …

Development And Characterization Of Mycelium-Based Biocomposites From Ganoderma Lucidum Using Spent Yerba Mate And Residual Sunflower Oil For Sustainable Insulation In Construction, Paula V. Alfieri, Guadalupe Canosa

Journal of Sustainable Construction Materials and Technologies

The construction industry urgently requires sustainable alternatives to petroleum-based insulation materials such as expanded polystyrene (EPS) and mineral wool. Mycelium-based biocomposites offer a promising solution by valorizing agricultural waste while delivering competitive thermal and acoustic performance. In this study, developed and characterized biocomposites using Ganoderma lucidum mycelium combined with spent yerba mate and residual sunflower oil (70 g/30 mL), both commonly generated as waste in Argentine institutions. Two formulations were evaluated: high density (HD: 280 ± 5 kg/m³) and low density (LD: 185 ± 5 kg/m³). Samples were cultivated for 90 days at 28 °C and 65% relative humidity and …

Comparative Life Cycle Assessment Of Hemp Walls In Residential Construction In Morocco, Hicham Kaddouri, Rachida Elbarghmi, Firyal Latrache, Marwane Hammouti, Abderrahim Abidouche, Ismael Driouch

Journal of Sustainable Construction Materials and Technologies

This study analyzes the energy and environmental performance of hemp-based wall solutions applied to Moroccan residential buildings by combining dynamic thermal simulation and life cycle assessment (LCA). A reference building is assessed under four representative Moroccan climates (Al Hoceima, Oujda, Marrakech, and Ouarzazate), comparing a conventional wall retrofitted with hemp plaster and a wall incorporating hemp concrete. The results show that hemp concrete significantly reduces annual heating and cooling energy demands by 20–24% depending on the climate, with heating needs decreasing by up to 40% and cooling needs by approximately 15%, particularly in hot and arid regions. The LCA reveals …

Dual-Waste Integration For Geotechnical Improvement: Silica Fume And Eggshell Ash In Kaolin Soil Stabilization, Ng Jun Shen, Muzamir Hasan, Siti Sarah Eliyun, Md. Ikramul Hoque, Mohamad Afiq Jazrin Mohamad Sidek

Journal of Sustainable Construction Materials and Technologies

This study reveals the potential substitution of silica fume and eggshell ash in the technique of soil stabilization, varying across distinct proportions in the modification of geotechnical parameters. The untreated kaolinitic soil which has low soil bearing capacity in nature is frequently reflected in its mechanical instability, for instance, soil settlement and extreme compressibility. By associating the industrial and agricultural material, it is potentially to resolve the above-mentioned issues with explicit designs. A number of laboratory approaches have been implemented in the assessment of basic geotechnical properties, including grain size distribution, Atterberg limits, specific gravity, proctor properties, and shear strength …

Application Of Cost-Effective High-Resolution Remote Sensing To Characterize Flooding In Mountain River Corridors, Ishwar Joshi, Ian Gowing, Brian M. Crookston

Civil and Environmental Engineering Student Research

This study evaluated a cost-effective UAV-based multi-sensor approach for characterizing river corridor conditions during and after moderate floods in two mountain river corridors in Northern Utah, USA: the Logan River and Blacksmith Fork River. These study reaches included urban, rural, and agricultural areas, hydraulic structures and bridges, and fish passage structures. A DJI Matrice 300 UAV was used with two separate payloads: an AgEagle Altum-PT multispectral camera and an R3 Pro V2 two-return LiDAR system. The workflow included UAV flight planning and data collection, post-processing of the multi-spectral and LiDAR sensor data, spatial resolution and accuracy assessment, and interpretation of …

Identifying Failure Behaviors In Stereolithography From Varied Print Orientations, Kevin Veltre

Theses and Dissertations

Stereolithography (SLA) is an additive manufacturing (AM) technique that utilizes photopolymerization to create three-dimensional shapes by strategically printing layers of material. Printing parameters such as layer orientation, print resolution and post cure can affect a specimen’s homogeneity, longevity and mechanical characteristics. Because of this variability, print parameters must be carefully considered when designing products and print processes for desired components, as manufacturers often fail to include all relevant print settings when advertising mechanical properties. For this study, 130 SLA-printed specimens were created with 100-micron print layer thickness and print orientations varying between 0 and 90, including intermediate orientations, to observe …

Understanding Structural Risk: Seismic Demand For Low-Fill Slender Fuel Tanks, David Yang, Sam Anderson

Civil and Environmental Engineering Faculty Publications and Presentations

Older fuel storage tanks, such as those in Oregon's CEI Hub, present significant seismic vulnerabilities, prompting proposals to limit storage capacity as a transitional risk mitigation measure before more permanent retrofitting actions. However, a critical knowledge gap exists regarding the applicability of standard analysis methods, like API 650, to low-fill conditions. This study utilizes the Veletsos-Yang iterative fluid-tank interaction procedure to evaluate the seismic demand of low-fill slender tanks. The analysis reveals that low-fill slender tanks exhibit slightly longer impulsive periods compared to fully-filled tanks with identical fill-height to radius ratios. Furthermore, the fixed roof mass of a low-fill tank …

Impact Of Asphalt Binder Chemical Composition On The Performance Of Asphalt Mixture., Sagar Parajuli

LSU Master's Theses

Asphalt binder is composed of four chemical fractions, namely, saturates, aromatics, resins, and asphaltenes (SARA). Binders with the same performance grade (PG) can exhibit different chemical compositions due to variability in crude oil sources and refining processes. The objective of this study was to evaluate how such chemical variations influence the mechanical performance of asphalt mixtures at high, intermediate and low temperatures.

Eighteen 12.5-mm nominal Maximum Aggregate Size mixtures were designed using two aggregate types (limestone and gravel), and three binder grades (PG 67-22, PG 70-22m and PG 76-22m), each from three different sources with varying chemical fractions. A suite …

Feasibility Of Using Untreated And Treated Rice Straw Fibers As A Modifier For Hot Mix Asphalt, Aditya Chowdhury

Civil Engineering Theses

Flexible pavements are subject to progressive deterioration driven by repeated traffic loading, environmental exposure, and material degradation, which causes distress. This study presents an integrated research framework that combines laboratory performance evaluation of rice straw fiber (RSF)-modified hot mix asphalt with machine learning-based pavement distress prediction to advance sustainable pavements. Three plant-produced HMA mixtures were modified with untreated and alkali-treated RSF at dosage levels of 0.2%, 0.4%, and 0.6% by total mixture weight. FTIR spectroscopic analysis confirmed that alkali treatment induced significant chemical modifications to the fiber surface, increasing hydroxyl group availability and enhancing fiber–binder adhesion. Alkali-treated RSF consistently outperformed …

Incorporating Increased Road User Costs Into Pavement Management Modeling: A Case Study Of Two-Lane Rural Highways, Khaled A. Abaza, Mohamed S. Yamany

Faculty Publications

The impact of increased road user costs on optimal pavement rehabilitation plans has been investigated using a simplified pavement management model. The increased road user costs include elevated vehicle operating costs (VOCs) due to work-zone lane closures and traveling on severely deteriorated pavements. A model is proposed for estimating the VOC for work-zone lane closures on two-lane rural highways, considering both stopping and idling costs. Another model for approximating the increased VOC associated with driving on poor/bad pavements is suggested as a function of the relevant VOC rate and a proportionality factor. Sample results are presented for a two-lane rural …

Fuel Tank Seismic Stability Program-Informed Displacement Maps Of Portland's Critical Energy Infrastructure Hub, Ana Tijerina Esquino

Dissertations and Theses

Oregon's Critical Energy Infrastructure (CEI) Hub in northwest Portland contains a large portion of the state's liquid fuel storage and distribution capacity and is located in an area susceptible to liquefaction and earthquake-induced permanent ground deformation during a Cascadia Subduction Zone earthquake. Initial Seismic Vulnerability Assessments submitted under Oregon's Fuel Tank Seismic Stability program provide valuable facility-specific information, but the assessments vary in subsurface characterization, treatment of fine-grained soils, ground motion selection, and deformation estimation methods. This variability complicates interpretation of regional seismic risk and motivates a consistent corridor-scale analysis.

This thesis develops CPT-informed displacement estimates for representative cross sections …

Policy Analysis Of The Inclusion Of Mitigation Measures In The Re-Design And Construction Of The New Frances Scott Key Bridge, Patrick John O'Connor

Theses and Dissertations

This thesis discusses the tragic event of the container ship MV Dali impacting the Francis Scott Key Bridge on March 26, 2024, leading to the collapse of the structure and killing six people despite having collision mitigation protections in place. This research examines how late twentieth-century structures are inadequate for current shipping demands and emphasizes that updated mitigation design criteria must accommodate larger modern vessels as governments replace or upgrade these structures. This paper will examine four case studies of different collisions that have similar circumstances to the Francis Scott Key Bridge collapse and review National Transportation Safety Board reports …

Fatigue And Healing Performance Of Asphalt Materials Modified With Nanomaterials And High-Polymer Asphalt Binders, Samuel M. Addai

Theses and Dissertations

Fatigue cracking is one of the primary distress mechanisms affecting asphalt pavement durability under repeated traffic loading and environmental aging. Although asphalt binders possess an inherent ability to heal micro-damage during rest periods, this healing capacity is often insufficient to fully counter progressive fatigue damage under field conditions. This thesis investigates the fatigue and self-healing behavior of asphalt binders and mixtures modified with nanomaterials and advanced polymer-based systems. Nanomodified binders were evaluated using Linear Amplitude Sweep (LAS) and Linear Amplitude Sweep with Healing (LASH) tests within the VECD framework to quantify fatigue resistance and healing behavior under different rest periods …

Transport Properties And Microstructural Development Of Co₂-Cured, Co₂-Infused, And Cold-Weather Concrete, Arlene Jane Looc

Theses and Dissertations

This research aims to advance the understanding of durability and transport behavior in emerging CO₂-cured and cold-weather concrete technologies. Limited work has examined long-term durability indicators such as permeability, resistivity, and pore connectivity in these types of concrete. To bridge this gap, the study evaluates transport properties alongside microstructural changes that govern the progression of hydration and the evolution of pore structure. This study measures transport properties, determines correlations between resistivity and fluid ingress, and analyzes the evolution of pore structure. To achieve this, the experimental program evaluated three concrete mixtures for external CO₂ exposure, nine for dry ice infusion, …

Performance Evaluation And Sustainable Benefits Of Using Metakaolin And Recycled Steel Fibers In Concrete, Lova Raju Surla, Ramprasad Naik Desavathu, Raja Murugadoss Jeyaraju

Journal of Sustainable Construction Materials and Technologies

The rapid accumulation of waste vehicle tires and the increasing demand for cement pose significant environmental challenges through land pollution and CO2 emissions. The combined use of recycled steel fibers (RSFs) recovered from waste tires and supplementary cementitious materials (SCMs) offers a sustainable solution to these issues. This study investigates concrete incorporating 20% fly ash (FA), varying metakaolin (MK) contents (4–16%), and RSF dosages of 0.5–1.5%. Mechanical properties (compressive, split tensile, and flexural strengths) and durability characteristics (sorptivity, water absorption, chloride permeability, and homogeneity) were evaluated at 7, 28, and 90 days. Results showed that the mixture containing 20% FA …

Climate-Responsive Design For Sustainable Construction: Passive Strategies In Domestic Architecture Supporting Sustainability, Nahed Chakouf

Journal of Sustainable Construction Materials and Technologies

This study explores climate-responsive design in domestic architecture, focusing on the application and effectiveness of passive strategies across various climatic regions, including the UK, hot-arid, tropical, and cold climates. A qualitative comparative case study method was used to explore different passive design strategies, integration of sustainability, procurement, the coordination of stakeholders, and compliance with regulations in residential architectural projects under varying climate conditions. Drawing from a combination of historical case studies and original architectural projects, the research evaluates how spatial configuration, material selection, solar orientation, shading, ventilation, and insulation are optimized to achieve thermal comfort and energy efficiency. In temperate …

Investigation Of Energy Efficiency Of An Autonomous Mobile Photovoltaic-Thermal (Pv/T) System With A Polycarbonate Absorber, Sanjar Kodir Ugli Shoguchkarov, Anvar Rakhmat Ugli Rakhmatov, Rushana Husen Kizi Abdullaeva, Orazbek Maratbay Ugli Temirbaev

Technical science and innovation

This study analyzes the enhancement of energy efficiency in photovoltaic-thermal (PV/T) systems, which enable the simultaneous generation of electrical and thermal energy from solar radiation. The research focus is an autonomous mobile unit based on multi-channel polycarbonate heat collectors with a hydraulic diameter of 8 mm, characterized by their lightweight nature and superior corrosion resistance compared to conventional metal absorbers. Experimental investigations were conducted at the solar testing field of the Physical-Technical Institute of the Academy of Sciences of Uzbekistan under extreme continental climatic conditions to determine the system's stable thermophysical indicators. The results demonstrated that active water cooling using …

Use Of New Improved Methods For Assessing The Engineering-Geological Characteristics Of Deposits By Depth (Using The Example Of The Akba Deposit)., Elboy Shavkatovich Qurbonov Salom, Abduboqib Djalilovich Karimov, Yokub Yarash Ugli Isomiddinov

Technical science and innovation

The article examines the fracturing and filtration properties of rocks in boreholes, rock outcrops, and underground mine workings at the Akba gold deposit. Based on the results of hydrogeological and engineering-geological studies, methods that fully meet modern requirements were used, the values of the RMR rating of rocks and the indicators of the qualitative content of RQD rocks, as well as the intervals of their changes, were studied, as a result of which it became possible to quickly and accurately assess the strength state of the rock mass of the deposit territory by depth and area.

Modeling Of Terpolymerization Kinetics And Determination Of Reactivity Ratios In The Tdma–Styrene–Maleic Anhydride System, Shohrux Boboxon Ugli Mavlonov, Sadriddin Fayzullayevich Fozilov

Technical science and innovation

In this study, the kinetics of terpolymerization, compositional evolution, and monomer reactivity ratios in the TDMA–styrene–maleic anhydride system were comprehensively investigated. Increasing the initiator concentration from 16.8×10⁻⁶ to 51.3×10⁻⁶ mol•L⁻¹ led to an increase in conversion from 6.4% to 15.2% and reaction rate from 4.075×10⁻⁶ to 8.965×10⁻⁶ mol•L⁻¹•s⁻¹. At low conversion (Xw≈0.02–0.09), the terpolymer composition remained close to the initial feed, although deviations due to differences in monomer reactivity were observed. With increasing conversion, some systems exhibited stable composition (±0.02), while others showed compositional drift (increase of MA fraction from 0.50 to 0.70). The determined reactivity ratios (rTDMA/St≈0.99; rSt/TDMA≈1.62; rTDMA/MA≈2.02; …

Development Of An Optimal Composition Of A Composite Solvent For Asphalt–Resin–Paraffin Deposits, Gulmira Abduvaliyevna Tadjiyeva, Xasan Irgashevich Kadirov, Shaxnoza Abduvaliyevna Tadjiyeva, Fazliddin Zokir Ugli Murodullayev, Bekmurodjon Baxtiyorjon Ugli Raximjonov

Technical science and innovation

A solvent formulation composed of aromatic hydrocarbons of the C9 fraction and aliphatic alcohols in a 1:1 ratio, supplemented with 1–3 wt.% of a nonionic surfactant, has been developed. The proposed composition demonstrates more than a twofold increase in dissolving and washing efficiency toward paraffin-type asphaltene–resin deposits. Furthermore, the solvent system exhibits pronounced depressant–dispersant properties with respect to paraffin-containing organic deposits. Although numerous investigations have addressed the development of technologies for removing organic deposits in oilfield equipment—primarily focusing on specific aspects of eliminating or preventing asphaltene–resin–paraffin deposits (ARPD) in wells—limited attention has been given to the design of integrated approaches. …

Technology For Obtaining Aliphatic Amines Based On Liquid By-Products Of Polymerization Processes, Kamila Sabirbaevna Allanazarova, Ulugbek Komiljonovich Urinov

Technical science and innovation

Polymerization processes generate considerable amounts of liquid secondary by-products, which are often underutilized despite their significant chemical potential. Addressing the need for sustainable resource use, this study aims to develop a technological method for converting these by-products into valuable aliphatic amines. The experimental approach involved the pre-treatment of liquid polymerization by-products through fractional distillation to isolate C3–C10 fractions, followed by catalytic amination using Raney nickel under controlled temperature (160°C) and pressure (12 atm) conditions. Analytical methods including gas chromatography-mass spectrometry (GC-MS) and Fourier-transform infrared spectroscopy (FTIR) were employed to characterize the reaction products. The results demonstrated the successful formation of …

Adaptive – Compositional Method For Coordinating Subsystems At Different Levels In Hierarchical Control Systems, Husan Zakirovich Igamberdiyev, Uktam Farxodovich Mamirov Mr, Inomjon Ilxom Ugli Abdukaxxarov Mr

Technical science and innovation

This paper examines the problem of synthesizing algorithms for the composition of subsystems at various levels within complex hierarchical control systems under conditions of uncertainty and resource constraints. It is demonstrated that classical composition algorithms, which rely on the intersection of admissible sets and the use of local optimality criteria, suffer from several significant drawbacks. These include a combinatorial increase in complexity, dependence on the expert selection of parameters, and limited applicability in dynamic environments. To overcome these shortcomings, an adaptive-compositional method is proposed. This method is based on the dynamic recalculation of coordination parameters, the integration of model predictive …

Calculation Of The Basic Parameters Of The Hybrid Power Plant (Hpu) On The Spark Car, Rustam Raximovich Tillahodjaev, Jamoliddin Pardaboy Ugli Turdiev

Technical science and innovation

This article presents one of the effective ways to improve fuel efficiency and reduce emissions of toxic substances, the use of internal combustion engines with the use of an electric drive in their designs. In recent years, two directions in the development of cars with electromechanical drives have been clearly identified, the first is the creation of a pure electric car, the second is the development of an electromechanical drive with a combined (hybrid) power plant. Due to the lack of efficient energy storage available for mass production, pure electric vehicles have relatively low mileage on a single charge. This …