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Articles 1 - 30 of 3893
Full-Text Articles in Civil Engineering
Treatment Of Municipal Solid Waste Incineration Bottom Ash Using Cement For Integrated Recovery Of Hydrogen And Production Of Supplementary Cementitious Material, Muhammad Haris Javed, Wenyu Liao, Fathma Zuhra, David Vollero, David Schmidenberg, Hongyan Ma
Treatment Of Municipal Solid Waste Incineration Bottom Ash Using Cement For Integrated Recovery Of Hydrogen And Production Of Supplementary Cementitious Material, Muhammad Haris Javed, Wenyu Liao, Fathma Zuhra, David Vollero, David Schmidenberg, Hongyan Ma
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
Municipal solid waste incineration (MSWI) bottom ash (MBA) represents both a disposal challenge and a potential resource for sustainable construction materials, including use as a supplementary cementitious material (SCM). However, the conventional use of MBA in cement-based materials is hindered by its high metallic aluminum content, which reacts in alkaline environments to release hydrogen gas and causes volumetric instability (e.g., expansion and cracking). This study investigates a cement-based alkali pretreatment method using diluted cement suspension to stabilize metallic aluminum and improve the compatibility of MBA as an SCM. Compared to conventional alkali solutions, the proposed approach avoids the direct use …
Mineral Composition-Driven Competitive Adsorption Behavior Of Superplasticizer In Recycled Concrete Powder-Cement Pastes: Quantification And Validation, Junpeng Du, Tongsheng Zhang, Hongyan Ma, Peiliang Shen, Yiqun Guo, Siqing Zeng, Jiangxiong Wei, Qijun Yu
Mineral Composition-Driven Competitive Adsorption Behavior Of Superplasticizer In Recycled Concrete Powder-Cement Pastes: Quantification And Validation, Junpeng Du, Tongsheng Zhang, Hongyan Ma, Peiliang Shen, Yiqun Guo, Siqing Zeng, Jiangxiong Wei, Qijun Yu
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
Recycled concrete powder (RCP) exhibits pronounced variability in mineral component contents, which leads to competitive adsorption of superplasticizers in RCP-Portland cement (PC) pastes and consequently to mineral composition-dependent deviations in rheological properties. In this study, limestone powder (LSP), quartz powder (QZP), and hardened paste powder (HPP) were used to simulate the main components of RCP. Effects of RCPs with target components on the rheological properties of blended cement paste were investigated, and a competitive-adsorption coefficient (CC) was proposed to quantify the competitive adsorption of superplasticizer. Results showed that increasing LSP-enriched RCP content reduced the yield stress of cement paste, primarily …
Multidimensional Total Quality Management And Its Effects On Sustainability And Performance In Industrialized Building System Projects, Felix Delmonte
Multidimensional Total Quality Management And Its Effects On Sustainability And Performance In Industrialized Building System Projects, Felix Delmonte
Mechanical and Civil Engineering Faculty Publications
This study develops and tests a multidimensional total quality management (TQM) framework to explain how distinct quality practices influence environmental sustainability, construction quality, cost and schedule performance, waste reduction, energy efficiency, stakeholder satisfaction, and overall project performance in industrialized building system (IBS) projects. Soft and hard TQM dimensions such as leadership commitment, customer focus, employee involvement, training and continuous improvement, process management, supplier quality, and data driven decision making are operationalised and linked to eight outcome constructs. Partial least squares structural equation modelling (PLS SEM) is used to estimate direct effects and to examine mediation by waste reduction and energy …
Ensemble Learning Framework For Predicting Close Proximity Tire–Pavement Noise On Expressways, Woo Young Cho, Jin Hwan Kim, Guk Gon Song, Kyungnam Kim, Youngguk Seo
Ensemble Learning Framework For Predicting Close Proximity Tire–Pavement Noise On Expressways, Woo Young Cho, Jin Hwan Kim, Guk Gon Song, Kyungnam Kim, Youngguk Seo
Faculty Articles
Traffic noise is a critical public health concern affecting millions of highway users and adjacent residents worldwide. In response, many transportation agencies have adopted functional surface materials to reduce noise at the source on pavement, but assessing their effectiveness remains expensive and logistically challenging. Close Proximity (CPX) testing quantifies tire-pavement noise but requires specialized equipment costing $50,000-$126,000 and is limited to existing pavement, preventing proactive noise assessment during pavement design. This study develops machine learning models to predict CPX noise levels from readily available pavement characteristics, eliminating the need for costly tests during design and planning phases. To train and …
Five-State Seismic Damage Classification Of Steel-Girder Bridges On Soft Soil Using Directional Intensity Measures And Multi-Parameter Damage Indices, Ibrahim Alomari, Woubishet Zewdu Taffese, Mohammad Hossein Afsharmovahed, Genda Chen
Five-State Seismic Damage Classification Of Steel-Girder Bridges On Soft Soil Using Directional Intensity Measures And Multi-Parameter Damage Indices, Ibrahim Alomari, Woubishet Zewdu Taffese, Mohammad Hossein Afsharmovahed, Genda Chen
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
Rapid yet accurate post-earthquake damage assessment of highway bridges is essential to ensure transportation network resilience. Traditional inspection, fragility analysis, and finite element modeling are time-consuming or inaccurate for real-time decision-making. This study compares ten machine-learning classifiers for the seismic damage states of highway steel-girder bridges that incorporate directional intensity measures to represent the variance of ground motions. Based on the nonlinear time-history analyses of two Missouri bridges, one Michigan bridge, and one Wisconsin bridge, multi-parameter structural damage indices were proposed and mapped to five damage states from none to collapse. Among ten supervised algorithms studied, the artificial neural network …
Effect Of Rheology Modification On Fiber Orientation And Dispersion In 3d-Printed Ultra-High-Performance Concrete, Haodao Li, Alfred Addai-Nimoh, Seongho Han, Kamal H. Khayat
Effect Of Rheology Modification On Fiber Orientation And Dispersion In 3d-Printed Ultra-High-Performance Concrete, Haodao Li, Alfred Addai-Nimoh, Seongho Han, Kamal H. Khayat
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
The extrusion process in 3D concrete printing (3DCP) facilitates horizontal alignment of steel fibers along the printing direction, thus enhancing the load-bearing capacity of printed elements. However, such shear-induced fiber alignment is highly sensitive to rheological properties. This study investigates how variations in dynamic yield stress (τd) and plastic viscosity (μ), influence the extrudability, fiber orientation and dispersion, and anisotropic mechanical behavior of ultra-high-performance concrete (UHPC). Five viscosity-modifying agent (VMA) types were incorporated at two content levels to modify the rheology of printable UHPC. Results showed that moderate VMA additions improved printability, whereas excessive contents markedly increased τd and μ; …
Human-Centered Electric Vehicle Adoption Framework For Smart Mobility: Modeling Perceived Range And Charging Anxiety As A Psychological Barrier, Fatemeh Nazari, Abolfazl (Kouros) Mohammadian, Thomas Stephens
Human-Centered Electric Vehicle Adoption Framework For Smart Mobility: Modeling Perceived Range And Charging Anxiety As A Psychological Barrier, Fatemeh Nazari, Abolfazl (Kouros) Mohammadian, Thomas Stephens
Civil Engineering Faculty Publications
Electric vehicles (EVs) offer a transformative pathway toward reducing the environmental, economic, and health-related externalities of internal combustion engine vehicles in urban settings. Despite substantial advances in battery technology, charging infrastructure expansion, and supportive policy incentives, EV penetration remains limited which poses challenges for smart and sustainable mobility planning. A critical yet insufficiently modeled barrier to adoption lies in the psychological perceptions surrounding electric driving range and charging reliability, which is commonly framed as “range anxiety,” but more broadly reflecting perceived range and charging anxiety. To address this gap, this study introduces a latent psychological construct capturing individuals’ perceived range …
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
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. …
How Does Competitive Adsorption Between Vma And Pce Influence Yield Stress Of Cement Paste? A Novel Insight From Interparticle Forces And Percolation Threshold, Huamin Sun, Le Teng, Xiaohan Yu, Xin Shu, Zhangli Hu, Jiaping Liu, Kamal H. Khayat
How Does Competitive Adsorption Between Vma And Pce Influence Yield Stress Of Cement Paste? A Novel Insight From Interparticle Forces And Percolation Threshold, Huamin Sun, Le Teng, Xiaohan Yu, Xin Shu, Zhangli Hu, Jiaping Liu, Kamal H. Khayat
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
Viscosity modifying admixture (VMA) and polycarboxylate superplasticizer (PCE) are often combined to optimize rheological properties of cement-based materials. However, the competitive adsorption of these complex admixtures can greatly influence rheological properties. Many studies have investigated the variation of yield stress due to competitive adsorption between VMA and PCE; but the mechanisms are not fully understood. This study aims to shed a new light on this question in cement paste systems prepared with low water-to-binder ratios of 0.16–0.30. The competitive adsorption of VMA and PCE was quantitatively assessed using the Total Organic Carbon and Ultraviolet-Visible Spectroscopy measurements. The effect of competitive …
An Ensemble Learning-Based Approach To Quantify Post-Earthquake Functional Recovery Of A Steel Moment-Resisting Frame Inventory, Mohsen Zaker Esteghamati, Shiva Baddipalli
An Ensemble Learning-Based Approach To Quantify Post-Earthquake Functional Recovery Of A Steel Moment-Resisting Frame Inventory, Mohsen Zaker Esteghamati, Shiva Baddipalli
Civil and Environmental Engineering Faculty Publications
The quest for seismic resiliency requires designing for performance objectives beyond life safety. Functional recovery is an emerging objective often defined as the time required to restore a building’s basic functionality to the pre-event level. Nevertheless, quantifying functional recovery is a complex, computationally intensive process that is challenging to integrate into a standard design workflow. This study develops a machine learning (ML) model to map design and geometric features of steel special moment-resisting frames (SMRFs) to their functional recovery under two hazard levels: design-basis (DBE) and maximum considered (MCE) earthquakes. First, functional recovery time was quantified for an inventory of …
Transforming Dredged Sediment Into Reactive Clay: Critical Review Of Calcination, Reactivity, And Sustainable Valorization As Supplementary Cementitious Material, Seongho Han, Sanghwon Wi, Koochul Ji, Keun Hyeok Yang, Farshad Rajabipour, Kamal H. Khayat, Jinyoung Yoon
Transforming Dredged Sediment Into Reactive Clay: Critical Review Of Calcination, Reactivity, And Sustainable Valorization As Supplementary Cementitious Material, Seongho Han, Sanghwon Wi, Koochul Ji, Keun Hyeok Yang, Farshad Rajabipour, Kamal H. Khayat, Jinyoung Yoon
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
Dredged sediment (DS) is generated worldwide in large volumes through routine port and waterway maintenance, yet its disposal presents environmental and economic challenges. Recently, calcined dredged sediment (CDS) has emerged as a supplementary cementitious material (SCM), offering a viable alternative to traditional SCMs, such as fly ash and slag cement. This review synthesizes current knowledge on the physical, chemical, and mineralogical characteristics of raw DS and pretreatment strategies aimed at dewatering, organic matter removal, and contaminant stabilization. The effects of calcination on the production of reactive amorphous aluminosilicates are also discussed. Emphasis is placed on physicochemical changes revealed by experimental …
Low-Carbon Concrete For Sustainable Construction: A Comprehensive Review Of Performance Characteristics, Implementation Challenges, And Decarbonization Pathways, Fazel Azarhomayun, Jingjie Wei, Kamal H. Khayat
Low-Carbon Concrete For Sustainable Construction: A Comprehensive Review Of Performance Characteristics, Implementation Challenges, And Decarbonization Pathways, Fazel Azarhomayun, Jingjie Wei, Kamal H. Khayat
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
Reducing the carbon footprint of concrete has become a central objective in sustainable construction. Low-carbon concrete (LCC), developed primarily through clinker reduction, supplementary cementitious materials, and alternative binder strategies, offers a promising route for lowering embodied emissions while maintaining the performance requirements of structural concrete. This comprehensive review consolidates the current state of knowledge on LCC, identifies critical research and implementation gaps, and examines its material composition, mixture-design methodologies, performance characteristics, structural applications, implementation challenges, and decarbonization pathways. Single-SCM systems have been reported at clinker-replacement levels approaching 50%, although durability at these replacement levels, particularly carbonation resistance, remains system- and …
Recent Advances In The Rheological Properties Of Ultra-High-Performance Concrete: A Critical Review, Le Teng, Kamal H. Khayat, Jiaping Liu
Recent Advances In The Rheological Properties Of Ultra-High-Performance Concrete: A Critical Review, Le Teng, Kamal H. Khayat, Jiaping Liu
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
Ultra-high-performance concrete (UHPC) with adapted rheology continues to attract interest considering the requirement for novel processing techniques such as self-consolidating, pumping, spraying, and three-dimensional (3D) printing. The rheology of UHPC is complex due to its high solid volume fraction, low water content, and wide range of constituent materials that affect its flow properties. This work provides guidance for tailoring the mixture proportioning of UHPC to secure proper rheological properties and performance of UHPC for various applications. In the first part of this work, key physical, physicochemical, and chemical factors that can affect the rheological properties of UHPC are discussed. Rheological …
Field Monitoring And Geometric Representation Of A Uhpc-Repaired Bridge Structure, Robert Lawler
Field Monitoring And Geometric Representation Of A Uhpc-Repaired Bridge Structure, Robert Lawler
Honors Scholar Theses
Ultra-High Performance Concrete (UHPC) has shown promise in bridge rehabilitation broadly, but its application to steel gusset plate repair represents a novel use case with limited prior research. Therefore, when the Commodore Isaac Hull Bridge in Derby, Connecticut, was issued an emergency declaration due to gusset plate section loss, a UHPC repair was implemented. This project represented the first known field implementation of this type of UHPC gusset plate repair, marking a significant advancement in the rehabilitation of deteriorated steel bridge components. To support long-term performance assessment and ensure the success of the repair, field monitoring efforts were also incorporated …
Optimizing Copper Slag As A Sustainable Precursor For Iron Phosphate Cement: Hydration Mechanism, Phase Transformation, And Environmental Safety, Wei Wang, Hongyan Ma, Xiunan Cai, Dan Luo, Zhicheng Xu, Zhongqiu Luo, Xintao Zhou
Optimizing Copper Slag As A Sustainable Precursor For Iron Phosphate Cement: Hydration Mechanism, Phase Transformation, And Environmental Safety, Wei Wang, Hongyan Ma, Xiunan Cai, Dan Luo, Zhicheng Xu, Zhongqiu Luo, Xintao Zhou
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
Iron-rich copper slag (CS) has significant potential as a precursor for the synthesis of sustainable acid-base cement (AB). However, the roles and transformation behaviors of the diverse iron phases in CS during hydration remain unclear. In this study, the preparation conditions, early hydration behavior, transformation processes of iron components, and environmental safety of CS-based iron phosphate cement (CS-IPC) were systematically investigated. Under optimized conditions, with a CS/ADP mass ratio of 3.0 and a grinding time of 1.5 h, CS-IPC exhibited an initial setting time of 27.6 min and a flowability of approximately 159 mm. After curing for 3 and 28 …
Steel Corrosion In Underground Transportation Infrastructure, Amr M. Morsy, Islam A. Ebo, Shiv K. Janardhanan
Steel Corrosion In Underground Transportation Infrastructure, Amr M. Morsy, Islam A. Ebo, Shiv K. Janardhanan
Mineta Transportation Institute
Corrosion of buried steel, a critical component of American transportation infrastructure, remains one of the most insidious challenges due to the uncertainty associated with its estimates. Predicting when and how this corrosion happens is very difficult. This uncertainty grows exponentially with time, making corrosion estimation in the long term even more challenging, especially with buried steel and steel structures, which cannot even be monitored visually. While significant advancement has been made to understand the effect of the various corrosion parameters on soil corrosivity, there is a lack of a comprehensive understanding of how these factors collectively contribute to corrosion as …
Optimization Of The Baffle Geometry Of A Circular Culvert Outlet Structure To Maximize Energy Dissipation, Kiarash Shirmahi
Optimization Of The Baffle Geometry Of A Circular Culvert Outlet Structure To Maximize Energy Dissipation, Kiarash Shirmahi
Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research
High-velocity flow at culvert outlets can lead to significant soil erosion and damage to downstream infrastructure, particularly in agricultural regions where land protection is critical. Circular culverts, commonly used in transportation systems, are especially susceptible to this issue due to flow acceleration caused by geometric constraints and installation angles. Despite extensive research on energy dissipation in rectangular culverts, limited attention has been given to circular configurations. This study addresses this gap by evaluating the hydraulic performance of baffle systems designed to reduce outlet energy in circular culverts.
A series of laboratory experiments was conducted using a scaled physical model of …
Computer Vision And Machine Learning Approaches For Defect Detection In 3d-Printed Cementitious Materials: A Systematic Review, Muhammad Ali Musarat, Ruben Paul Borg, Jingjie Wei, Carl James Debono, Kamal Khayat
Computer Vision And Machine Learning Approaches For Defect Detection In 3d-Printed Cementitious Materials: A Systematic Review, Muhammad Ali Musarat, Ruben Paul Borg, Jingjie Wei, Carl James Debono, Kamal Khayat
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
3D printing is evolving at a fast pace in both the manufacturing and construction sectors. These advancements can greatly benefit these industries. However, the 3D printing of concrete structures presents some challenges due to defects in the 3D concrete printed elements. Hence, this study systematically reviews Artificial Intelligence (AI)-driven techniques, such as Computer Vision and Machine Learning, to identify surface defects that can occur in 3D-printed cementitious material structures. The adopted methodology was the PRISMA statement with the aim of reporting the systematic review and meta-analysis. Two well-known databases, Web of Science and Scopus, were utilised for data extraction of …
Enameling Coating Of Pipes: Thermal Proprieties And Corrosion Tests, Signo Reis, Genda Chen, Mike Koenigstein, Liang Fan
Enameling Coating Of Pipes: Thermal Proprieties And Corrosion Tests, Signo Reis, Genda Chen, Mike Koenigstein, Liang Fan
Materials Science and Engineering Faculty Research & Creative Works
Enamel coating on pipelines can be done in several ways such as the wet process, plasma spray, and electrostatic process. Wet process requires little capital expenses and provides an acceptable finish for industrial applications particularly when the part to be coated is small. Electrostatic process of enamel powder is most promising to coating large pipelines in field conditions. The enamel coating applied by the electrostatic process is very consistent and smooth since each particle is glass only. However, the powder is very fragile until fired and the charge retention is lowered in high humidity conditions. Coupons cut from a full-size …
Factors Affecting Pedestrian-Vehicle Conflicts: An Empirical Analysis, Christo D. Jamo
Factors Affecting Pedestrian-Vehicle Conflicts: An Empirical Analysis, Christo D. Jamo
Honors Scholar Theses
The number of pedestrian deaths increased by 78% between 2009 and 2023, while other motor vehicle crash deaths increased by 13% in the same period [1]. To identify potential pedestrian safety measures, this study analyzed the effects of location-based demographics, pedestrian phasing type, and other physical infrastructure and behavior variables on the probability of pedestrian-vehicle conflicts at signalized intersections, which is a surrogate measure of crash risk. Data were collected from 55 intersections in Connecticut, and the pedestrian-vehicle interactions were classified by severity based on the Swedish Traffic Conflict Technique: undisturbed passage, potential conflict, minor conflict, or serious conflict. Because …
Problems With Small Drinking Water Systems In Developing And Developed Countries: How Do They Compare?, Kurt Kesteloot
Problems With Small Drinking Water Systems In Developing And Developed Countries: How Do They Compare?, Kurt Kesteloot
Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–
This dissertation compares the factors that drive the long-term functionality of small drinking water systems (serving fewer than 10,000 people) in developing and developed country contexts, with a focus on groundwater supplies. Using regression analysis in SAS and complementary fuzzy-set Qualitative Comparative Analysis (fsQCA) for developing countries, the study integrates two datasets: 23 Engineers Without Borders project surveys (90+ variables across 14 countries) and a multi-year National Park Service inspection dataset (approximately 1,561 systems; 7,460 recorded deficiencies, enriched with U.S. Census ZIP-code aggregates). In developing countries, statistically significant predictors of success include government cash contributions (odds ratio [OR] ≈ 67.6), …
Ai-Driven Detection Of Failure Modes In Thermoplastic Composites Using Acoustic Emission Techniques, M. M. Shahzamanian, Li Ai, Paul Ziehl
Ai-Driven Detection Of Failure Modes In Thermoplastic Composites Using Acoustic Emission Techniques, M. M. Shahzamanian, Li Ai, Paul Ziehl
Civil Engineering Faculty Publications
Composite materials in aircraft structures can suffer impact damage that leaves barely visible yet structurally significant defects, which degrade mechanical performance, especially under compressive loads. Existing methods for identifying failure modes in compression after impact (CAI) tests using acoustic emission (AE) data are limited in accuracy and scope. This study introduces an approach combining AE sensing with a heterogeneous ensemble convolutional neural network (CNN) to detect and classify failure mechanisms in impacted composite specimens. The novelty of this work lies in employing Red, Green, and Blue (RGB) wavelet images, produced through continuous wavelet transform (CWT) of AE signals, as inputs …
Application Of Fidic Epc/Turnkey Contract Under The Egyptian Public Works Contracts Law, Ahmed Alhady Dr., Mahmoud Mahmoud Ahmed Eng., Ahmed Elhakeem Prof., Mohamed Ibrahim Dr.
Application Of Fidic Epc/Turnkey Contract Under The Egyptian Public Works Contracts Law, Ahmed Alhady Dr., Mahmoud Mahmoud Ahmed Eng., Ahmed Elhakeem Prof., Mohamed Ibrahim Dr.
Civil Engineering
This study focuses on the application of FIDIC Conditions of Contract for EPC Turnkey Projects—Silver Book 1999, (FIDIC (EPC&T)), when governed by the Egyptian Law of Contracts concluded by public bodies No. 182 of 2018 (ELC) due to the conflicts that may arise from such application. Hence, this study identifies specific FIDIC (EPC&T) 1999 clauses that have the potential for conflicts with ELC, shows the similarities and disparities between these clauses and the relevant ELC articles, and provides recommendations to ensure the successful application of FIDIC (EPC&T) 1999 under ELC. This was achieved through a multistep research methodology in which …
Hybrid Deep Learning Model For Accurate Settlement Forecasting Of Metro Tracks Under Canal Diversion Engineering, Haijie He, Zhenlin Wang, Sifan Shen, Shiyu Sheng, Jing Zhang, Chuang He, Huafeng Shan, Qiongfang Zhang, Li Ai
Hybrid Deep Learning Model For Accurate Settlement Forecasting Of Metro Tracks Under Canal Diversion Engineering, Haijie He, Zhenlin Wang, Sifan Shen, Shiyu Sheng, Jing Zhang, Chuang He, Huafeng Shan, Qiongfang Zhang, Li Ai
Civil Engineering Faculty Publications
The structural stability of metro systems is essential for safe and reliable urban rail operation. Large-scale underground construction may influence existing metro lines, making accurate settlement prediction necessary. Traditional empirical and numerical methods often fail to capture long-term settlement behavior. This study predicts track bed settlement of Hangzhou Metro Line 1 using monitoring data collected during the Grand Canal diversion construction. A hybrid model (CEEMDAN-BWO-BiLSTM-ATT model) integrating Complete Ensemble Empirical Mode Decomposition with Adaptive Noise, Beluga Whale Optimization, Bidirectional Long Short-Term Memory, and an attention mechanism is developed. Results from four monitoring points along the up line show good performance, …
Intelligent Cost-Optimized Mix Design Prediction And Engineered Strength System For Geopolymer Concrete: A Machine Learning-Based Recommender System, Yuvaraj Natarajan, K.R. Sri Preethaa, V. Danushkumar, Syed Muhammad Oan Naqvi, M. Shyamala Devi, Karen Lozano, Bubryur Kim, Jinwoo An
Intelligent Cost-Optimized Mix Design Prediction And Engineered Strength System For Geopolymer Concrete: A Machine Learning-Based Recommender System, Yuvaraj Natarajan, K.R. Sri Preethaa, V. Danushkumar, Syed Muhammad Oan Naqvi, M. Shyamala Devi, Karen Lozano, Bubryur Kim, Jinwoo An
Civil Engineering Faculty Publications
Geopolymer concrete is a promising low-carbon alternative to ordinary Portland cement concrete, but its practical use is limited by complex mix-design requirements and limited cost-aware decision-support tools. This study developed the Intelligent Cost-Optimized Mix Design Prediction and Engineered Strength System (iCOMPRESS), a machine learning-based recommender system that integrates 28-day compressive strength prediction, cost optimization, and compositionally diverse mixture recommendation. A database of 443 literature-derived mixtures was used to train a hyperparameter-optimized Random Forest model with domain-informed features related to binder chemistry, alkaline activation, water content, aggregates, and curing conditions. The model achieved a five-fold cross-validation mean absolute error (MAE) of …
From Our Stories, To Our Streets (Osos), Jennifer Lopez
From Our Stories, To Our Streets (Osos), Jennifer Lopez
Student Publications
Youth traffic safety persists as a critical planning challenge and public health concern in New Mexico, where pedestrian fatality rates consistently rank among the highest in the United States (National Highway Traffic Safety Administration, NTSA, Governors Highway Safety Association, GHSA, 2023; Baca, 2025). Students (children), due to their daily interactions with roadways, whether when they walk, bike, ride transit, or drive/get driven to and from school, are among the most vulnerable groups within the transportation system (Ferenchak, N. Wesley, M., 2017. For many students in Albuquerque, the commute to or from school is one of the most dangerous parts of …
Effect Of Curing Duration On Bridge Deck Concrete Performance, Zhaniya Omarova
Effect Of Curing Duration On Bridge Deck Concrete Performance, Zhaniya Omarova
Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research
This study evaluates the influence of curing duration on the performance of bridge deck concrete and investigates the feasibility of reducing curing periods without compromising structural and durability properties. Two concrete mixtures, a standard Nebraska Department of Transportation (NDOT) bridge deck mix (47BD) and an optimized reduced-cement-content mix (O47BD-R100), were evaluated under multiple curing durations Fresh, early-age, mechanical, durability, and shrinkage properties were assessed to characterize the effect of curing on concrete behavior. Internal relative humidity and temperature were monitored using embedded sensors to investigate moisture diffusion and its role in shrinkage development for lab specimens and full-scale slabs.
Results …
What Holds High-Speed Rail Back: Lessons From Global Systems And California’S Experience, Deepak K. Sharma, Rajnish Lekhi, Scott Parr
What Holds High-Speed Rail Back: Lessons From Global Systems And California’S Experience, Deepak K. Sharma, Rajnish Lekhi, Scott Parr
Mineta Transportation Institute
This report examines benefits and challenges of integrating California High-Speed Rail (CHSR) with other rail systems and reviews California legislation impacting HSR’s contracting and financing alternatives. The research compares CHSR with high-speed rail systems around the world to identify similarities and differences in costs, speeds, ridership, and operating conditions. It also reviews Japan’s Land Readjustment Act as a model for value capture and land assembly and explores international experiences on rail integration, along with U.S. cases from the East Coast and Los Angeles. A review of California’s transportation legislation highlights how laws for highways and bridges differ from those for …
Equity Evaluation Of Residents’ Transit+Walk Accessibility To Sacramento Healthcare Facilities, Masoud Ghodrat Abadi, Ahoura Zandiatashbar, Aaron Pickett, Stephanie Nemet, Soheil Sharifi
Equity Evaluation Of Residents’ Transit+Walk Accessibility To Sacramento Healthcare Facilities, Masoud Ghodrat Abadi, Ahoura Zandiatashbar, Aaron Pickett, Stephanie Nemet, Soheil Sharifi
Mineta Transportation Institute
Access to healthcare is a key component of public health equity, yet many U.S. communities remain dependent on private vehicles for medical travel. This study introduces an integrated framework, the Transit+Walk Score (TWS), to evaluate how effectively residents of Sacramento, California, can reach healthcare facilities via public transit and how safely, comfortably, and conveniently they can walk from transit stops to those facilities. The research aims to inform planners, transit agencies, and policy makers in designing equitable and multimodal transportation systems. The research team combined geospatial network modeling and field-based walkability audits to assess 123 healthcare facilities across Sacramento, with …
A Novel Optuna-Vmd-Ml Framework For Enhanced Settlement Prediction Of Buildings Around Foundation Pits, Jing Zhang, Zhenlin Wang, Shiyu Sheng, Sifan Shen, Chuang He, Huafeng Shan, Haijie He, Li Ai
A Novel Optuna-Vmd-Ml Framework For Enhanced Settlement Prediction Of Buildings Around Foundation Pits, Jing Zhang, Zhenlin Wang, Shiyu Sheng, Sifan Shen, Chuang He, Huafeng Shan, Haijie He, Li Ai
Civil Engineering Faculty Publications
The prediction of building settlement around foundation pit is of vital importance to ensure the safety and stability of urban construction projects. However, current predictions of buildings surrounding foundation pit face numerous challenges. Therefore, this study proposes a framework that integrates Optuna-based hyperparameter optimization, variational mode decomposition (VMD), and machine learning (ML) for accurate and timely settlement prediction in practical engineering scenarios, referred to as the Optuna–VMD–ML framework. Optuna is employed to tune the hyperparameters of both VMD and the ML models; the Optuna-tuned VMD decomposes the settlement time series into mode components, which are then used to train the …