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Full-Text Articles in Civil Engineering

Assessment Of Adaptation And Diffusion Of Biogas Technology A Case Study Of Dar Es Salaam City, Tanzania, Doreen L. Tarimo Jan 2025

Assessment Of Adaptation And Diffusion Of Biogas Technology A Case Study Of Dar Es Salaam City, Tanzania, Doreen L. Tarimo

Tanzania Journal of Engineering and Technology (TJET)

This study investigated the adaptation and diffusion of biogas technology in Dar es Salaam, driven by the increasing need for sustainable energy solutions. The study’s is rooted in addressing urban energy challenges and providing an eco-friendly waste management alternative. Various factors, including socioeconomic variables, technical efficiencies, and community-level acceptability, were examined to assess the technology’s adaptability and diffusion. Data collection methods and techniques included lab analysis using American public health association (APHA) standard methods, interviews, questionnaire administration the data analysis was undertaken using statistical package for the social sciences (SPSS) with a sample size comprising 100 household heads from Mburahati, …


Mitigating The Impacts Of Future Climate Change On Urban Infrastructure In Alabama Through Updating Precipitation Intensity-Duration-Frequency (Idf) Curves, Kofi Ntow Opare Jan 2025

Mitigating The Impacts Of Future Climate Change On Urban Infrastructure In Alabama Through Updating Precipitation Intensity-Duration-Frequency (Idf) Curves, Kofi Ntow Opare

All ETDs from UAB

Climate change is set to profoundly impact urban infrastructure, causing increased flooding and storm damage, necessitating the reevaluation and adaptation of design methodologies to account for increasing precipitation extremes. This dissertation aims to enhance the resilience of urban infrastructure in Alabama by updating Precipitation Intensity-Duration-Frequency (IDF) curves, which are crucial for designing stormwater management systems, drainage networks, and flood control structures. Traditional IDF curves, derived from historical rainfall data, operate under the assumption of stationarity, an assumption increasingly invalidated by climate change. This research employs the Generalized Extreme Value (GEV) distribution and compares the efficacy of L-moments and Generalized Maximum …


Pfas In Landfill Leachate: Practical Considerations For Treatment And Characterization, Fabrizio Sabba, Christian Kassar, Teng Zeng, Synthia P. Mallick, Leon Downing, Patrick J. Mcnamara Jan 2025

Pfas In Landfill Leachate: Practical Considerations For Treatment And Characterization, Fabrizio Sabba, Christian Kassar, Teng Zeng, Synthia P. Mallick, Leon Downing, Patrick J. Mcnamara

Civil and Environmental Engineering Faculty Research and Publications

Per- and polyfluoroalkyl substances (PFAS) are widely used in consumer products and are particularly high in landfill leachate. The practice of sending leachate to wastewater treatment plants (WWTPs) is an issue for utilities that have biosolids land application limits based on PFAS concentrations. Moreover, landfills may face their own effluent limit guidelines for PFAS. The purpose of this review is to understand the most appropriate treatment technology combinations for mitigating PFAS in landfill leachate. The first objective is to understand the unique chemical characteristics of landfill leachate. The second objective is to establish the role and importance of known and …


Performance And Economic Evaluation Of Asphalt-Based High Friction Surface Treatment (Hfst) Applications, Alireza Roshan, Magdy Abdelrahman Jan 2025

Performance And Economic Evaluation Of Asphalt-Based High Friction Surface Treatment (Hfst) Applications, Alireza Roshan, Magdy Abdelrahman

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

High Friction Surface Treatments (HFSTs) are recognized for enhancing friction between tires and road surfaces, with reduced road accidents being a key benefit. Epoxy-based HFSTs, though widely used, come with challenges like compatibility issues with existing pavements, higher installation and removal costs, and reduced durability tied to substrate quality. Recently, state agencies have increasingly focused on developing asphalt-based alternative binders for HFST applications as highlighted in the National Cooperative Highway Research Program (NCHRP) RFP #NCHRP 10-145. This study introduces asphalt-based HFSTs as an alternative to traditional epoxy-based treatments. Various aggregate types were examined for friction performance and the effect of …


Class-Wise Histogram Matching-Based Domain Adaptation In Deep Learning-Based Bridge Element Segmentation, Tarutal Ghosh Mondal, Zhenhua Shi, Haibin Zhang, Genda Chen Jan 2025

Class-Wise Histogram Matching-Based Domain Adaptation In Deep Learning-Based Bridge Element Segmentation, Tarutal Ghosh Mondal, Zhenhua Shi, Haibin Zhang, Genda Chen

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study focused on the problem of domain shift in deep learning-based bridge element segmentation. The impracticability of accounting for all possible variabilities vis-à-vis structural shape, size, color, texture, illumination, and other operational conditions in the training process leads to the deterioration in the model performance when applied to test data from novel unseen domains. In such situations, rebuilding the model with labeled training data from the target domain becomes prohibitively expensive and time-consuming in many practical cases. Recent advancements in unsupervised domain adaptation techniques are known to provide viable solutions to this problem. However, it was observed in this …


Aqueous Carbonation Of Steel Slags: A Comparative Study On Mechanisms, Nannan Zhang, Gao Deng, Wenyu Liao, Hongyan Ma, Chuanlin Hu Jan 2025

Aqueous Carbonation Of Steel Slags: A Comparative Study On Mechanisms, Nannan Zhang, Gao Deng, Wenyu Liao, Hongyan Ma, Chuanlin Hu

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study investigated the aqueous carbonation mechanisms of three typical steel slags: ladle metallurgy furnace (LMF) slag containing high Al content, electric arc furnace (EAF) slag featuring high Si content and relatively low Al content, and ladle-arc fusion (LAF) slag with medium-Al content. It was found that the carbonation kinetics of the three slags were similar and followed the surface coverage model within the first 6 h of carbonation. Initially, the carbonation process was primarily governed by the reaction product precipitation. After 3 h of carbonation, the process was dominated by mineral dissolution, controlled by the uncovered reactive sites. The …


Integrating Off-Spec Scms Into Plc Blends, George A. Qubty Jan 2025

Integrating Off-Spec Scms Into Plc Blends, George A. Qubty

Civil Engineering Theses - Archive

Off-spec supplementary cementitious materials (SCMs) remain underutilized due to variability in reactivity and non-conformance with existing standards. This study evaluates the hydration behavior and fresh-state and mechanical performance of these materials in Portland limestone cement (PLC) systems. One Class F fly ash (FA), one bottom ash (BA), and two calcined clays (HACC and LACC) were evaluated as 20 % replacements to PLC. Hydration behavior was characterized using isothermal calorimetry and thermogravimetric analysis (TGA), while fresh-state and mechanical performance were assessed through flow table, Vicat setting time, load–crack mouth opening displacement (CMOD) flexural testing, and compressive strength testing. HACC increased compressive …


Implementation And Performance Evaluation Of Plastic Road Mix Design In Parking Lot, Ishraq Faruk Jan 2025

Implementation And Performance Evaluation Of Plastic Road Mix Design In Parking Lot, Ishraq Faruk

Civil Engineering Dissertations - Archive

The uncontrolled proliferation of plastic waste has emerged as a global environmental crisis, with high-density polyethylene (HDPE) constituting a substantial fraction of the waste stream due to its extensive use in packaging and its resistance to degradation. In parallel, asphalt pavements particularly in urban infrastructure such as parking lots experience accelerated deterioration from raveling, rutting, and cracking as a result of thermal cycling, repetitive loading, and inadequate drainage. These converging challenges present an opportunity for innovative, circular-economy-based sustainable pavement technologies that simultaneously improve surface durability and mitigate plastic waste accumulation.

This research investigates the full-scale implementation and monitoring of HDPE …


Citizen-Centric Building Energy Retrofits: Understanding And Supporting Citizens As Occupants, Participants, Decision-Makers, And Learners In Home Energy Retrofits, Nikhil Singh Yaduvanshi Jan 2025

Citizen-Centric Building Energy Retrofits: Understanding And Supporting Citizens As Occupants, Participants, Decision-Makers, And Learners In Home Energy Retrofits, Nikhil Singh Yaduvanshi

Civil Engineering Dissertations - Archive

Residential building retrofits remain significantly under-adopted despite substantial technological advances, economic incentives, and policy efforts, creating a critical gap between technical potential and actual implementation in achieving climate goals. Assessment of citizen involvement in building retrofit processes plays a critical role in formulating effective home retrofit program designs to ensure maximum adoption rates and avoid energy waste. Although, existing retrofit programs and decision-making models recognize the importance of citizen involvement, the extent of citizen capabilities and the effects of citizen-centered approaches on retrofit adoption and building performance has not been comprehensively examined. The adoption and success of retrofit programs depends …


The Development Of Sustainable Synthetic Fiber Reinforced Concrete Mix Design With Low Maintenance Cost, Kentesha L. High Jan 2025

The Development Of Sustainable Synthetic Fiber Reinforced Concrete Mix Design With Low Maintenance Cost, Kentesha L. High

Civil Engineering Dissertations - Archive

This dissertation presents the mix design of polypropylene SYN-FRC as an alternative to traditional concrete mixtures in construction roadways. The primary scope of work was to develop and implement a pavement system at The University of Texas at Arlington, specifically designed for the Dallas area, to minimize long-term maintenance. Additionally, the project aimed for expeditious construction to avoid traffic closure during new construction and maintenance. It also involved evaluating the pavement performance, providing the City of Dallas with specifications for the mix design of SYN-FRC. The sustainability of the synthetic fiber mix design for concrete roadways, compared to traditional concrete, …


Assessment Of Long Term Durability Of Prefabricated Frp Strip Systems For The Rehabilitation Of Concrete, Karunya Kanagavel Jan 2025

Assessment Of Long Term Durability Of Prefabricated Frp Strip Systems For The Rehabilitation Of Concrete, Karunya Kanagavel

Civil Engineering Theses - Archive

Fiber Reinforced Polymer (FRP) composites provide an extremely effective means of rehabilitating deteriorating and understrength concrete elements due to their characteristics of high specific strength and stiffness, corrosion resistance, and potential long-term durability, lightweight nature, and ease of placement in the field. Despite significant use of these materials, there is still a lack of long-term durability data. With this in mind, the current study investigates the impact of environmental exposure and aging on 3 commercially available prefabricated carbon fiber reinforced composite strips and their recommended adhesives used in externally bonded rehabilitation with the aim of providing a comprehensive set of …


A Framework For Ai Implementation In Construction: Use Cases, Challenges, And Benefits For Contractors, Jaqueline De Aquino Leite Gomes Jan 2025

A Framework For Ai Implementation In Construction: Use Cases, Challenges, And Benefits For Contractors, Jaqueline De Aquino Leite Gomes

Theses and Dissertations--Civil Engineering

The construction industry is one of the most important sectors that contribute to the economy worldwide, but it has been very slow in adopting digital transformation. Artificial Intelligence is the backbone of digital innovation, and it can help solve inefficiencies, improve safety, and enhance decision-making in construction. This thesis reviews 85 academic papers, identifies 354 AI use-cases, 180 benefits, and 173 challenges. Key findings have looked at the role of AI in safety monitoring, design optimization, and operational efficiency, while barriers involve data scarcity, high costs, and readiness of the workforce.

All of these challenges have one very handy framework …


Flexural Post-Cracking Performance Of Macro Synthetic Fiber Reinforced Super Workable Concrete Influenced By Shrinkage-Reducing Admixture, Jingjie Wei, Nima Farzadnia, Kamal H. Khayat Jan 2025

Flexural Post-Cracking Performance Of Macro Synthetic Fiber Reinforced Super Workable Concrete Influenced By Shrinkage-Reducing Admixture, Jingjie Wei, Nima Farzadnia, Kamal H. Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Most literature has focused on the effect of shrinkage-reducing admixture (SRA) in shrinkage mitigation resistance of concrete. This study aims to examine the impact of SRA on the efficiency of macro synthetic fibers (MSF) in enhancing the flexural post-cracking behavior of fiber-reinforced super workable concrete (FR-SWC). A comparative analysis of the influence of fiber combinations on the flexural post-cracking behavior of beams is also included. Results showed that a higher dosage of SRA, particularly at 5 % by mass of binder, had a noticeable negative impact on flexural post-cracking performance of beams while exhibiting positive effect on workability and shrinkage …


Seasonal Variation Of The Stream’S Autogenic Sediment Transport Regime, Melissa Beckman Jan 2025

Seasonal Variation Of The Stream’S Autogenic Sediment Transport Regime, Melissa Beckman

Theses and Dissertations--Civil Engineering

This thesis investigates the autogenic sediment transport regime in a low-gradient stream system in the inner bluegrass region of central Kentucky, USA The seasonality of sediment transport seasonality was not well addressed in prior research for baseflow and low flow periods, to our knowledge, due to the assumption that low flows do not account for considerable fluid transport capacity to move sediment. The hypothesis is that during the autogenic regime the sediment transport in the low-gradient system is being driven by geophysical, biogeochemical, and biological processes. We hypothesize that crayfish are one mechanical driver of sediment transport during these periods. …


Bond Behavior Of Magnesium Potassium Phosphate Cement (Mkpc) Coating For Steel Reinforcement, Eric Williams Jan 2025

Bond Behavior Of Magnesium Potassium Phosphate Cement (Mkpc) Coating For Steel Reinforcement, Eric Williams

Masters Theses

"This research investigates the bond behavior of magnesium potassium phosphate cement (MKPC) coated mild steel deformed bars in conventional concrete and concrete repair materials. For typical steel reinforcement in concrete, a thin “passive layer” develops around the reinforcement, which protects the reinforcement from corrosion. The concrete carbonates over time, reducing the protection of the passive layer and allowing chlorides, which corrode the reinforcement, to penetrate at an increasing rate. In some cases, to combat this corrosion, a protective layer is added to the reinforcement prior to installation. Common protective layers include epoxy coatings or zinc galvanization. MKPC is a novel …


System Design For Highly Accurate And Efficient Target Detection In Triaxial Testing, Qingqing Fu Jan 2025

System Design For Highly Accurate And Efficient Target Detection In Triaxial Testing, Qingqing Fu

Masters Theses

Accurate and automated recognition of coded targets is crucial for high-precision photogrammetry-based measurements in triaxial testing. Traditional recognition methods, including those based on deep learning and table decoding, often struggle with issues such as perspective distortion, rotation, and variable lighting, leading to unreliable results. While deep learning approaches offer some improvements, they remain computationally intensive and sensitive to environmental factors.

This thesis introduces an innovative system that replaces deep learning algorithms with a blob analysis-based method for efficient and robust recognition of coded targets. The system also employs newly designed solid points of varying sizes and patterns, eliminating the need …


Exploring The Feasibility Of Innovative Integration Of Phase Change Materials For Thermo-Adaptive Asphalt Pavements, Farshad Saberi Kerahroudi Jan 2025

Exploring The Feasibility Of Innovative Integration Of Phase Change Materials For Thermo-Adaptive Asphalt Pavements, Farshad Saberi Kerahroudi

Doctoral Dissertations

"Current research examined the feasibility and efficiency of employing phase change materials (PCMs) in asphalt pavement materials to result in thermo-adaptive asphalt pavement. The PCM was introduced to the asphalt materials in three different scales, including asphalt binder, asphalt mastic, and asphalt mixture. After investigating asphalt at different scales, mix blending method was found as the easiest method without any complexity to mix asphalt binder with PCM. The testing results could reveal an improvement in the high temperature performance of asphalt binder without sacrificing the low temperature performance with the presence of PCM and Gilsonite. Also, introducing PCM to asphalt …


พฤติกรรมความล้าของแผ่นพื้นคอนกรีตเสริมเหล็กที่ได้รับการเสริมกำลังด้วยแผ่นพอลิเมอร์เสริมแรงด้วยเส้นใยอารามิด, ภัทรพงษ์ ปุญจุบัน Jan 2025

พฤติกรรมความล้าของแผ่นพื้นคอนกรีตเสริมเหล็กที่ได้รับการเสริมกำลังด้วยแผ่นพอลิเมอร์เสริมแรงด้วยเส้นใยอารามิด, ภัทรพงษ์ ปุญจุบัน

Chulalongkorn University Theses and Dissertations (Chula ETD)

ปัญหาความเสียหายของแผ่นพื้นคอนกรีตเสริมเหล็กจากแรงกระทำซ้ำ เป็นประเด็นสำคัญที่ส่งผลต่อความทนทานและอายุการใช้งานของพื้นสะพานคอนกรีตในสภาพแวดล้อมจริง งานวิจัยนี้จึงมุ่งศึกษาพฤติกรรมของแผ่นพื้นคอนกรีตเสริมเหล็กภายใต้แรงกระทำรวมศูนย์ ทั้งในสภาวะแรงกระทำแบบสถิตและแรงกระทำซ้ำ พร้อมประเมินประสิทธิภาพของการเสริมกำลังด้วยแผ่น AFRP strand sheet เพื่อพิจารณาความเหมาะสมของวิธีการเสริมกำลังดังกล่าวในงานบำรุงรักษาโครงสร้างสะพาน การทดสอบถูกออกแบบให้ครอบคลุมทั้งตัวอย่างที่ไม่ได้เสริมกำลังและตัวอย่างที่เสริมกำลัง โดยพฤติกรรมโครงสร้างที่สนใจประกอบด้วยความแข็งเกร็งหลังแตกร้าว การกระจายแรงภายในแผ่นพื้น พฤติกรรมรอยแตกร้าว การกระจายความเครียด และลักษณะการวิบัติภายใต้สภาวะที่ใกล้เคียงกับการใช้งานจริง จากผลการศึกษาพบว่าแผ่นพื้นที่เสริมกำลังด้วย AFRP มีพฤติกรรมโครงสร้างที่มีเสถียรภาพมากขึ้น สามารถควบคุมพัฒนาการของรอยแตกร้าวได้ดี และมีความทนทานต่อแรงกระทำซ้ำสูงกว่าแผ่นพื้นทั่วไป ความเสียหายสะสมลดลงอย่างมีนัยสำคัญ และโครงสร้างยังคงรักษาสมรรถนะได้ดีหลังผ่านการรับแรงกระทำซ้ำ ผลการวิจัยชี้ให้เห็นว่า AFRP strand sheet เป็นวิธีเสริมกำลังที่มีประสิทธิภาพในการเพิ่มความต้านทานต่อแรงกระทำซ้ำ เพิ่มความแข็งเกร็งหลังแตกร้าว นำไปสู่การยืดอายุการใช้งานของแผ่นพื้นคอนกรีตเสริมเหล็ก ซึ่งสอดคล้องกับความต้องการในการปรับปรุงความทนทานของแผ่นพื้นสะพานคอนกรีตเสริมเหล็กในงานวิศวกรรมโครงสร้างปัจจุบัน


Assessment Of The Feasibility Of Utilizing Plastic Waste In Infrastructure To Promote Circular Economy In Bangladesh, Md Lutfor Rahman Jan 2025

Assessment Of The Feasibility Of Utilizing Plastic Waste In Infrastructure To Promote Circular Economy In Bangladesh, Md Lutfor Rahman

Civil Engineering Dissertations - Archive

This study presents a comprehensive assessment of municipal solid waste (MSW) and plastic waste characterization across Bangladesh, with a focus on circular economy opportunities and the long-term economic viability of plastic road. Using on-site waste characterization data for 13 major cities from four geographic zones of Bangladesh —Northwest, Northeast, Southwest, and Southeast—the research identifies food waste as the dominant component of the national waste stream (67.3%), followed by plastic (12.4%), textiles (7.8%), and paper (4.7%). Among plastics, low-density polyethylene (LDPE) overwhelmingly dominates (89.7%), highlighting the continued prevalence of single-use flexible plastics.

A life cycle cost analysis (LCCA) was conducted comparing …


A Multi-Method Geophysical Approach For Complex Shallow Landslide Characterization, Mohammadyar Rahimi, Clinton Wood, Meersad Fathizadeh, Salman Rahimi Jan 2025

A Multi-Method Geophysical Approach For Complex Shallow Landslide Characterization, Mohammadyar Rahimi, Clinton Wood, Meersad Fathizadeh, Salman Rahimi

Civil Engineering Faculty Publications and Presentations

This case study demonstrates the value of combining multiple non-invasive geophysical methods to characterize a landslide along Highway 7 near Jasper, Arkansas, USA. Geophysical testing was conducted using Multichannel Analysis of Surface Waves (MASW), Horizontal to Vertical Spectral Ratio (HVSR), and Electrical Resistivity Tomography (ERT), supplemented by select soil borings. The geophysical investigation aimed to provide a high-resolution, near-continuous view of subsurface conditions, including bedrock depth and the location of the groundwater table or highly saturated zones within the slide area. These factors are important contributors to slope instability. The MASW results revealed a highly variable depth to weathered bedrock …


Accelerated Test Method (Atm) For The Evaluation Of External Sulfate And Chloride Attack On Concrete Using Artificial Climate Environment (Ace): An Assessment Of Methodology, Eli Walker Jan 2025

Accelerated Test Method (Atm) For The Evaluation Of External Sulfate And Chloride Attack On Concrete Using Artificial Climate Environment (Ace): An Assessment Of Methodology, Eli Walker

College of Graduate Studies: Theses & Dissertations

This study seeks to investigate a testing methodology that utilizes accelerated testing methods (ATM) in conjunction with nondestructive testing methods (NDT) to assess destructive ion attacks on concrete. Through the testing of concrete samples, the impacts of chloride and sulfate ions on concrete will be tested by subjecting concrete to cyclic testing in an artificial climate environment. Electrical resistivity (ER) and ultrasonic pulse velocity (UPV) testing will evaluate the impact of the accelerated testing on the migration of destructive ions within the pore structure of the tested concrete. Based on this investigation, comparisons between accelerated, non-accelerated, and control samples will …


Effect Of Gluconate Molecules On The Reaction Kinetics Of C-(N)-A-S-H And N-A-S-H Gel Formation, Jiafeng Kong, Chao Sun, Zuhua Zhang, Chenglong Cai, Yubin Cao, Yanru Wang, Hongyan Ma, Xuesen Zeng, Hao Wang Jan 2025

Effect Of Gluconate Molecules On The Reaction Kinetics Of C-(N)-A-S-H And N-A-S-H Gel Formation, Jiafeng Kong, Chao Sun, Zuhua Zhang, Chenglong Cai, Yubin Cao, Yanru Wang, Hongyan Ma, Xuesen Zeng, Hao Wang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Organic ligands are widely used to regulate setting in cementitious binders, yet their chemistry-selective action in geopolymers (GPs) remains unclear. Here we isolate the role of sodium gluconate (SG) in early reaction kinetics across a Ca-rich GP that forms a calcium-(sodium)-aluminosilicate hydrate (C-(N)-A-S-H) gel and a Ca-poor GP that forms a sodium-aluminosilicate hydrate (N-A-S-H) gel. Four GPs spanning Ca/Si ≈ 1.01 to 0.01 were prepared with identical activator chemistry and dosages of SG up to 5 wt.% of precursors. Setting time, isothermal calorimetry, pore-solution speciation (TOC, ICP-OES, and pH), selective dissolution (reaction extent), low-field1H NMR, XRD, FTIR, SEM-EDS, …


Every Publication Needs An Author Verified Tl;Dr Statement, Sarah Oerther, Daniel B. Oerther Jan 2025

Every Publication Needs An Author Verified Tl;Dr Statement, Sarah Oerther, Daniel B. Oerther

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

No abstract provided.


Behavior Of Reinforced Concrete Beams With Externally Anchored Rebars, Nyan Soe Lynn Jan 2025

Behavior Of Reinforced Concrete Beams With Externally Anchored Rebars, Nyan Soe Lynn

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study investigates a minimally invasive rehabilitation method for reinforced concrete (RC) beams using externally anchored reinforcement by means of epoxy. Two programs were conducted: flexural rehabilitation using externally anchored longitudinal bars, and shear rehabilitation using externally anchored U-shaped stirrups. Four beam specimens were tested under four-point bending for the flexural program, and four under three-point bending for the shear program. Test results from the flexural program showed large deformation due to plastic hinge formation. Due to their unbonded nature, the external rebars engaged later than the internal reinforcement and developed large deflection. Load-carrying capacity, however, was not increased since …


การศึกษาความเป็นไปได้ในการประยุกต์ใช้ปัญญาประดิษฐ์ระบบหลายเอเจนต์ผสานคอมพิวเตอร์วิทัศน์ เพื่อพัฒนาระบบติดตามวัสดุเหล็กกล่องในงานก่อสร้าง, ปภพ รัตนพันธุ์ Jan 2025

การศึกษาความเป็นไปได้ในการประยุกต์ใช้ปัญญาประดิษฐ์ระบบหลายเอเจนต์ผสานคอมพิวเตอร์วิทัศน์ เพื่อพัฒนาระบบติดตามวัสดุเหล็กกล่องในงานก่อสร้าง, ปภพ รัตนพันธุ์

Chulalongkorn University Theses and Dissertations (Chula ETD)

อุตสาหกรรมการก่อสร้างเผชิญความท้าทายในการจัดการวัสดุ เช่น เหล็กกล่อง ซึ่งเป็นต้นทุนหลัก เนื่องจากปัญหาข้อมูลไม่ถูกต้อง การสูญหาย และการพึ่งพาระบบเอกสาร ขณะที่เทคโนโลยีเดิมยังมีข้อจำกัด งานวิจัยนี้จึงนำเสนอการประยุกต์ใช้ปัญญาประดิษฐ์เพื่อระบบการติดตามวัสดุชนิดเหล็กกล่องในงานก่อสร้างตั้งแต่กระบวนการส่งมอบ คลังวัสดุ และการใช้งานวัสดุ ระบบที่พัฒนาขึ้นใช้โมเดลภาษาขนาดใหญ่ (Large Language Model: LLM) เป็นแกนกลางควบคุม ระบบหลายเอเจนต์ (Multi-agent Systems) ซึ่งประกอบด้วยเอเจนต์ตรวจจับและนับวัสดุด้วย คอมพิวเตอร์วิทัศน์ (Steel detect count Agent) และเอเจนต์บันทึกข้อมูล (Data collection Agent) โดยผู้ใช้สามารถโต้ตอบผ่านส่วนติดต่อผู้ใช้งานเชิงสนทนาบนเว็บแอปพลิเคชัน โดยระบบได้บูรณาการเทคโนโลยี BIM, YOLOv11, Gemini 2.5 Pro, LangGraph Supervisor และ ฐานข้อมูล Supabase จากการประยุกต์ใช้ในโครงการกรณีศึกษา ได้ใช้พารามิเตอร์ Precision, Recall และ F1-Score ในการประเมินการทำงานของเอเจนต์พบว่าเอเจนต์ตรวจจับและนับวัสดุมีค่า F1-Score สูงถึง 98.25-100% และเอเจนต์บันทึกข้อมูลมีค่า 100% ในทุกพารามิเตอร์ และส่งผลให้เอเจนต์ตัวแทนควบคุมหลักประมวลผลข้อมูลส่วนใหญ่ได้อย่างถูกต้อง ยกเว้นข้อมูล quantity ที่มีค่า F1-Score อยู่ที่ 92.86% ซึ่งเป็นข้อผิดพลาดที่เกิดจากเอเจนต์ตรวจจับและนับวัตถุก่อนหน้า และการประเมินการแสดงผลข้อมูลของวัสดุ แสดงให้เห็นว่าระบบบันทึกข้อมูลได้จริงตลอดทั้ง 3 กระบวนการ อีกทั้งเหล็กกล่องถูกนำไปติดตั้งได้อย่างครบถ้วน


การประยุกต์ใช้เหล็กกล่องเติมด้วยคอนกรีตกำลังสูงเป็นเสาในโครงสร้างที่พักอาศัย, พีรดนย์ ลอออรรถพงศ์ Jan 2025

การประยุกต์ใช้เหล็กกล่องเติมด้วยคอนกรีตกำลังสูงเป็นเสาในโครงสร้างที่พักอาศัย, พีรดนย์ ลอออรรถพงศ์

Chulalongkorn University Theses and Dissertations (Chula ETD)

งานวิจัยนี้มีวัตถุประสงค์เพื่อศึกษาและประเมินสิทธิภาพของโครงสร้างเหล็กกล่องเติมด้วยคอนกรีตกำลังสูง (High-Strength Concrete-Filled Steel Tube, HSCFST) สำหรับการประยุกต์ใช้กับบ้านพักอาศัย อันเป็นการตอบสนองต่อปัญหาการขาดแคลนแรงงานฝีมือ การเพิ่มขึ้นของค่าแรง และความจำเป็นในการลดระยะเวลาการก่อสร้างและต้นทุน การศึกษาได้พิจารณากรณีบ้านพักอาศัยสูง 3 ชั้น จำนวน 4 หลัง โดยทำการจำลองโครงสร้างด้วยโปรแกรม ETABS เพื่อตรวจสอบพฤติกรรมการรับแรงในแนวดิ่งและแรงจากแผ่นดินไหวของโครงสร้าง ซึ่งการออกแบบเสาเหล็กกล่องเติมด้วยคอนกรีตกำลังสูงอ้างอิงมาตรฐาน AISC 360-22 (LRFD) ผลการออกแบบพบว่าสามารถลดขนาดเสาให้เล็กลงเหลือ 125 มิลลิเมตร และ 150 มิลลิเมตร เพื่อให้มีขนาดไม่เกินความหนาของผนังบ้านได้เมื่อใช้คอนกรีตที่มีกำลังรับแรงอัดสูงกว่า 60 เมกะปาสคาล ร่วมกับเหล็กกล่องชนิดที่มีจำหน่ายในท้องตลาด โดยโครงสร้างที่ได้ออกแบบทั้ง 4 หลัง พบว่ามีประสิทธิภาพในการรับน้ำหนักบรรทุกและแรงแผ่นดินไหวดีกว่าโครงสร้างคอนกรีตเสริมเหล็กแบบเดิมในทุกด้าน ทั้งยังพบว่ามีต้นทุนการก่อสร้างที่ต่ำกว่าเสาคอนกรีตเสริมเหล็กอย่างมีนัยสำคัญ นอกจากนี้ยังได้ทำการทดสอบเสาเหล็กกล่องเติมด้วยคอนกรีตกำลังสูงในห้องปฏิบัติการ เพื่อเปรียบเทียบกำลังรับแรงอัดกับค่าที่ได้จากสมการทำนายตามมาตรฐาน AISC 360-22 พบว่าค่าที่ได้จากการคำนวณมีค่าต่ำกว่าผลการทดสอบจริงค่อนข้างมาก ส่งผลให้เกิดความมั่นใจยิ่งขึ้นต่อการนำเสาเหล็กกล่องเติมด้วยคอนกรีตกำลังสูงไปใช้จริงในงานก่อสร้างบ้านพักอาศัย


Centralized Deep Reinforcement Learning For Homogeneous Multi-Component Maintenance Optimization, Joseph W. Wittrock Jan 2025

Centralized Deep Reinforcement Learning For Homogeneous Multi-Component Maintenance Optimization, Joseph W. Wittrock

Theses and Dissertations

This thesis explores an application of reinforcement learning (RL) in maintenance optimization. Recent advances in hardware-accelerated computation and deep learning have made RL a powerful tool for solving optimization problems which are too complex for traditional methods. Maintenance optimization involves improving the efficiency and effectiveness of maintenance activities through data-driven approaches, ultimately reducing costs and increasing asset availability. Making informed maintenance decisions is crucial to long-term sustainability.

A desirable maintenance policy maximizes a utility signal while minimizing the cost of maintenance. Techniques in sequential decision making such as dynamic programming (DP) and RL have found success in optimizing these maintenance …


Coastal Flooding Along The Lower Brazos During The Landfall Of Hurricane Beryl -A Model-Based Investigation, Sabiha Tasnuva Khan Jan 2025

Coastal Flooding Along The Lower Brazos During The Landfall Of Hurricane Beryl -A Model-Based Investigation, Sabiha Tasnuva Khan

Civil Engineering Theses - Archive

Hurricane Beryl generated a complex hydrodynamic response along the Texas coast and Lower Brazos River, producing storm surge, elevated coastal water levels, intense rainfall, and widespread inundation. Low-gradient coastal rivers such as the lower portion of the Brazos River are particularly sensitive to the interaction of these drivers, yet the inland decay of surge energy and its interplay with watershed runoff remain poorly quantified. This study aims to characterize the physical mechanisms controlling water-level amplification, flow reversal, surge attenuation, and inundation development during Hurricane Beryl along the Lower Brazos and to determine the relative contributions of surge and rainfall to …


Stable Oxygen And Hydrogen Isotopic Ratios Of Precipitation And Modelling Of Precipitation Sources In Central Kentucky, Usa, 2017-2022, Ariel Gold-Mccoy Jan 2025

Stable Oxygen And Hydrogen Isotopic Ratios Of Precipitation And Modelling Of Precipitation Sources In Central Kentucky, Usa, 2017-2022, Ariel Gold-Mccoy

Theses and Dissertations--Civil Engineering

Our goals were to carry out analyses of a multi-year δ¹⁸O and δ²H dataset of precipitation from central Kentucky and to analyze the source of precipitation for storm events from 2017 to 2022. δ¹⁸O and δ²H were measured for 244 weekly precipitation samples collected by the National Atmospheric Deposition Program at Mackville, Kentucky, USA. Modelling precipitation source was carried out using HYSPLIT model for 414 events. Results of δ¹⁸O and δ²H from central Kentucky show: consistent seasonality, including summer highs and winter lows for δ¹⁸O and δ²H; correlation with air temperature; and …


An Investigation Of The Legitimacy Of The Underlying Assumptions Of The Scs Curve Number Method By Application To Actual Urban Watersheds, Robert K. Peterson Jan 2025

An Investigation Of The Legitimacy Of The Underlying Assumptions Of The Scs Curve Number Method By Application To Actual Urban Watersheds, Robert K. Peterson

Theses and Dissertations--Civil Engineering

The Soil Conservation Service (SCS) Curve Number (CN) method is widely used to estimate direct runoff, and its TR-55 urban-adapted Curve Numbers are commonly applied in stormwater design. However, the underlying assumptions of the method have been the subject of contemporary review, and concerns remain that these values underestimate runoff in actual urban watersheds. This study evaluates the performance of TR-55 CNs using rainfall–runoff data from twenty real-world urban watersheds in the National Stormwater Quality Database.

Empirical Curve Numbers were derived using two calibration techniques, the asymptotic CN method (CN∞) and a nonlinear least-squares optimization method (CNLS), and …