Civil and Environmental Engineering Commons^™

Comparative Study On Pouring Timing Of Sealing Hinge Concrete For Concrete-Filled Steel Tube Arch Bridge, Wang Xiaoliang, Fu Kaige, Zhang Song, Wang Zhongqiang, Chen Zhuoyi

Journal of China & Foreign Highway

The pouring timing of sealing hinge concrete for concrete-filled steel tube arch bridges directly affects the construction duration and the stress state of arch ribs. To clarify the structural response differences at different pouring timings, the Beiliuhe Extra-large Bridge on the Pingxi ‒ Cenxi Expressway in Guangxi Province was taken as the engineering background in this paper. A finite element model was established using Midas Civil, and the following four pouring timings of sealing hinge concrete were comparatively analyzed: immediately after the butt welding of sealing hinge steel pipes; after the closure of arch ribs and before the pouring of …

Study On Calculation Method For Incremental Launching Based On Nonlinear Analysis, Mo Shanfeng, Huang Cailiang, Qin Hui

Journal of China & Foreign Highway

In view of the shortcomings of traditional incremental launching calculation methods and the assembly construction control of incremental launching beams, an incremental launching calculation method based on nonlinear analysis was proposed in this paper. This method could truly simulate the running state where the incremental launching pier remains stationary, and the beam moves forward. The assembly alignment of all segments of the beam and the real alignment of the beam under specified working conditions could be directly output. The prefabricated alignment of the main beam (i.e., unstressed alignment) did not need to be consistent with the slide alignment. When the …

Summary And Prospect Of Typical Diseases In Energy Transport Channels In Winter Cold Regions Over Past 20 Years, Jia Qinlong, Hou Zhongfei, Yin Yanping

Journal of China & Foreign Highway

To investigate the typical disease characteristics of energy transport channels in winter cold regions and guide the design for extending road service life, the causes of diseases such as pavement reflective cracks, continuous potholes on bridge decks, and failures of bridge drainage systems were analyzed based on the 20-year operation data of a 531 km in-service expressway in the coal energy region of northern Shaanxi. The research results indicate that when the asphalt pavement thickness reaches 22 cm, the reflective crack spacing of the expressway operated for 15 years can be controlled to over 50 m. Basically, no base layer …

A Hybrid Mechano-Thermal Route To Synthesize Reactive Pozzolans From Clay Minerals: A Case Of Kaolinite, Oluwadamilare Charles Adesina, Bryan K. Aylas-Paredes, Brian R. Cherry, Luciano A. Gobbo, Aditya Kumar, Narayanan Neithalath

Materials Science and Engineering Faculty Research & Creative Works

Aluminosilicate resources from unconventional sources offer promising potential for developing low-carbon supplementary cementitious materials (SCMs), yet their activation typically requires energy-intensive thermal processing. Kaolinite is a geographically abundant and highly attractive precursor clay mineral to reduce the clinker factor in concrete. By integrating mechano- and thermo- chemistry sequentially in a novel hybrid mechano-thermal activation (MTA) strategy for clay mineral activation, the dehydroxylation of pure kaolinite polymorphs KGa-1b and KGa-2 for enhanced pozzolanic reactivity is unlocked at temperatures that are lower than those needed for conventional thermal activation (TA). The mechano-chemical activation (MCA) step that induces significant structural defects and disorder …

A Performance-Weighted Environmental Assessment Of Ultra-High-Volume Fly Ash Substitution In Portland Cement Concrete, Youngguk Seo, M.A. Karim, Teddy Tzvetkov, Joshua Hardy

Faculty Articles

Fly ash substitution for cement in Portland cement concrete (PCC) has been regarded as a sustainable solution, but its widespread application remains constrained by concerns over mechanical performance and durability of PCC, especially at higher replacement rates. This study evaluates PCC mixes incorporating fly ash Type C (FA-C) or Type F (FA-F) across cement replacement rates from 10% to 90%, tracking fresh-state workability, compressive strength, and surface electrical resistivity at 7, 14, and 28 curing days. A process-based life cycle assessment (LCA) with the TRACI 2.1 method quantified global warming potential (GWP, kg CO₂/m³) under a …

Characterization Of The Thermally Driven Red Hue Effect In Coated And Uncoated Concrete Systems: Implications For Post-Fire Assessment In Wildland Urban Interface Communities, Juan C. Palominos Jr

Master's Theses

The increasing frequency and intensity of Wildland-Urban Interface (WUI) wildfires, such as the destructive 2025 Pacific Palisades Fire that destroyed over 6,000 structures, have underscored the urgent need for rapid post-fire safety assessment methodologies. This study sought to quantitatively characterize the Thermally Driven Red Hue Effect (TRHE), a unique, irreversible color shift observed in architectural coatings and concrete substrates, to determine its reliability as a permanent visual record of thermal exposure. Concrete substrates were formulated with three distinct coarse aggregates: gold granite (14.7% Fe), red cinder (22.4% Fe), and green rock (33.6% Fe) and coated with a 20 PVC waterborne …

An Analytical Framework For Quantifying Urban And Community Resilience To Natural Hazards From Cell-Phone Gps-Location And Traffic-Flow Data, Georgios Chatzikyriakidis

Civil and Environmental Engineering Theses and Dissertations

Urban areas are increasingly exposed to natural hazards while accommodating a growing share of the global population, yet a consistent science-based framework for quantifying urban and community resilience remains lacking. This dissertation develops a physics-based analytical framework grounded in statistical mechanics and the quantitative theory of Brownian motion. A city is conceptualized as a complex medium in which citizens move analogously to Brownian particles within a viscoelastic environment, influenced by socioeconomic interactions and infrastructure functionality.

A central premise is that urban resilience, interpreted as engineering resilience (an outcome), can be quantified through a single metric: the mean-square displacement MSD=⟨r²(t)⟩, of …

A Maintenance-Aware Machine Learning Framework For Network-Level Highway Pavement Condition Prediction, Jin Hwan Kim, Guk Gon Song, Youngguk Seo

Faculty Articles

This study develops and validates maintenance-aware machine learning models for predicting the Highway Pavement Condition Index (HPCI) on the Korean expressway network. Multiple regression and tree-based models were trained and tested using the pavement condition surveys archived in the Highway Pavement Management System (HPMS). A stacking regressor that integrates random forest, gradient boosting, and extreme gradient boosting as base learners exhibited the most robust predictions. Performance metrics indicated that the stacking ensemble achieved a mean absolute error of 0.21, a root mean square error of 0.31, and a coefficient of determination exceeding 0.73 on the testing dataset. Also, the residuals …

In-Operando Imaging For Mechanistic Insights And Process Optimization In The Biofuel-Driven Combustion Synthesis Of Cement And Precursor Phases, Shubham Agrawal, Jeffrey J. Long, Aditya Kumar, Narayanan Neithalath

Materials Science and Engineering Faculty Research & Creative Works

Biofuel-based combustion synthesis (BCS) is a promising low-carbon pathway for decarbonizing cement production, providing an alternative to the fossil-fuel-driven clinkering process typically conducted at ∼1450 °C. Understanding microscale combustion mechanisms is essential to efficiently transfer biofuel-generated heat to cement precursors for targeted phase formation. Unlike previous studies focusing on macro-scale parameters such as fuel content/type, porosity, and holding temperature, this work provides mechanistic insights into microscale combustion behavior, linking microstructural phenomena with macro-scale processing conditions to guide parameter optimization. In-operando microscale imaging was employed to examine combustion wave propagation, spatio-temporal temperature evolution, and microstructural transformations within reactive pellets. Two combustion …

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 …

Comparative Study Of Cement-Rice Husk Ash Stabilized Bricks And Fired Clay Bricks, Daniel R. Samson, Emmanuel S. Leo

Tanzania Journal of Science

In some countries, fired clay bricks (FCBs) are widely used for construction, but their production is energy-intensive, relies largely on firewood, and contributes to deforestation and carbon emissions. This study explores unfired clay bricks stabilised with cement and rice husk ash (RHA) as a sustainable alternative, using Dakawa ward in the Morogoro Region, Tanzania, as a case study. The bricks, with a clay of plasticity index 17%, were stabilized with 6%, 10%, and 14% cement by mass, moulded into 40 mm cubes, and cured for 28 days. The compressive strengths achieved were 1.5, 3.6, and 4.1 MPa with water absorption …

Creation Of The 2-Way Cross Laminated Timber Subroutine For Computing Dynamic Analysis Parameters, Joseph Freitas

Architectural Engineering

This document will describe the inputs, methodology, and outputs for the CLT 2-way subroutine for cases with and without openings recently added to a proprietary structural analysis software. For the sake of simplicity, most of the discussion will be focused on cases without openings from here on out, as the verification process for a novel method for cases with openings is still in progress. The CLT 2-way module calculates multi-point resistance functions for panels without openings by automating the procedure outlined in an industry-standard structural design manual. The subroutine also finds the appropriate dynamic response factors, kinetic load multipliers, mass, …

Development Of A Novel Innovative Umbrella Falsework System For Concrete Slabs, Abdelazem Hashim

Theses and Dissertations

Formwork is one of the major elements that contribute to the cost and duration of concrete building projects. This is why optimizing such an element can lead to huge savings to all parties involved in the construction projects. With contractors facing huge challenges in such a competitive industry and employers seeking the least price and least duration for their projects, contractors are constantly under the obligations of finding the best alternatives to deliver their projects in terms of both time and money. Therefore, the main aim of this research project is to develop a falsework system, where the falsework system …

Co-Calcination Of Limestone And Clay Enhances The Performance Of Limestone Calcined Clay Cement (Lc3), Oluwadamilare Charles Adesina, Sahil Surehali, Avinaya Tripathi, Kayla Lauren Lee, Bryan K. Aylas-Paredes, Aditya Kumar, Narayanan Neithalath

Materials Science and Engineering Faculty Research & Creative Works

Limestone-calcined clay cements (LC³) reduce the environmental impact of cement production and accelerate the industry transition toward carbon neutrality. While conventional LC³ with 50% clinker replacement (LC³-50) demonstrate long-term performance comparable to ordinary Portland cement (OPC) in concrete, early-age performance is generally compromised. This study explores for the first time, joint thermal treatment—that is, co-calcination—of limestone (LS) and bulk kaolinitic clay in mass ratios of 1:1 to 1:4 under a calcination regime specifically designed to ensure activation of the clay mineral. The co-calcination converts a small fraction of LS to metastable CaO, thus providing an …

Data Set, R Scripts And Script Outputs For Manuscript: Manufacturing Systems: Characteristics And Dynamics, Alan J. Fitzmorris

Graduate Research Data

This file repository contains fifteen computer-generated datasets, two naturally occurring datasets, nineteen shipbuilding shop datasets, and sixty-one concrete plant datasets.  Each data set contains subdirectories associated with various aspects of the data analysis, including stationarity analysis, dynamic system analysis, and complexity analysis.  In each case, applicable R scripts are included.  The text file entitled “Directory_and_File_Names” depicts the directory structure and associated file names for a total of 225 directories encompassing 8008 files.

Buckling Analysis Of Auxetic Composite Laminates And Optimal Design Using Lamination Parameters And Machine Learning, Hans Bendon Maria Tamil Selvan

Mechanical and Aerospace Engineering Theses

Composite materials are widely used as structural panels in aerospace, automotive, and civil engineering applications, where buckling is often a critical failure mode. This thesis focuses on the analysis and design of composite laminates that maximize buckling performance under prescribed stiffness and thickness constraints.

The first part of the study investigates the buckling behavior of auxetic laminates, which exhibit a negative Poisson's ratio. While previous studies suggest that auxetic laminates can achieve higher critical buckling loads than non-auxetic laminates under simply supported boundary conditions with lateral restraint, the influence of other boundary conditions and plate aspect ratios has not been …

Thermal Transformations And Mechanical Properties Of All-D-Metal Mn2fecu Heusler-Type Shape Memory Alloy, Choji J. Daches, Joseph W. Newkirk, Mario Buchely

Materials Science and Engineering Faculty Research & Creative Works

All-d-metal Heusler alloys are emerging functional materials in which magnetic ordering, lattice distortion, and mechanical behavior are strongly coupled through d–d electronic interactions. This study systematically investigates the structural, thermal, magnetic, and mechanical properties of Mn₂FeCu synthesized within a Heusler-type compositional framework. SEM/EDS revealed a dual-phase FCC-based microstructure consisting of Mn–Fe–rich and Mn–Cu–rich domains, while XRD confirmed FCC symmetry with compositional partitioning rather than full L2₁ ordering. Differential scanning calorimetry identified partial melting of the Cu-rich phase near ~ 900 °C. Dilatometry showed a thermoelastic FCC → FCT transformation at ~ 770–780 °C with a recoverable strain of ~ 0.067%. …

The Effects Of Mold Flux Contamination On Oxide Scale Formation And Hydro-Descaling Efficiency During Steel Processing, Tochukwu Princewill Ojiako, Richard Osei, Mario Buchely, Haiming Wen, Simon Lekakh, Ronald O'Malley

Materials Science and Engineering Faculty Research & Creative Works

Oxide scale formation during thin-slab continuous casting has a complex structure, which is influenced by mold flux contamination, that modifies interfacial reactions during solidification, subsequent reheating, and descaling. While individual aspects of the oxidation behavior of carbon steel have been previously examined, the synergetic effects of mold flux contamination during continuous casting and subsequent reheating on scale modification and the efficiency of hydraulic descaling remain inadequately studied. This study quantitatively examines the effect of flux composition on oxide scale evolution, adhesion, and hydraulic removal in low-carbon steel under simulated industrial conditions. Slab samples with as-cast, cleaned, and flux-coated surfaces were …

Modeling Of Transformation Temperatures In Cast Martensitic Stainless Steels-Ca6nm: Effects Of Composition, Heating Rate, And Grain Size, Ugochukwu Agbedo, Mario Buchely, Laura Bartlett, Caelan Kennedy

Materials Science and Engineering Faculty Research & Creative Works

Accurate prediction of the critical transformation temperatures Ac1 and Ac3 is one of the essential factors in the heat treatment of CA6NM cast martensitic stainless steel. In this study, the influence of alloy composition, heating rate, and prior austenite grain size on the critical temperatures was quantified using dilatometric measurements and statistical modeling. Six heat treatment conditions produced prior austenite grain sizes ranging from ~75 to 247 µm. Experimental results showed that grain size variations produced only minor changes in Ac1 and Ac3, indicating a weak dependence of transformation temperatures on prior austenite grain size within the investigated range. In …

Multiphysics Simulation And Experimental Validation Of Phase Transformation And Hardness In Jominy End-Quenched Low-Alloy Steels, J. S. Alabi, E. Heidari, M. F. Buchely, K. Chandrashekhara, S. N. Lekakh, R. J. O'Malley, V. A. Athavale, A. Kumar

Materials Science and Engineering Faculty Research & Creative Works

High-volume industrial continuous hot-rolled steel heat treatment processes involve sophisticated multi-phase modeling. The performance of a given process can be optimized by coupling phase transformation kinetics with the cooling conditions of the process. This study develops a multiphysics model to simulate an intensive quenching process for steel, which is inherently transient and highly dependent on numerous parameters. The simulated object was a Jominy end-quenched specimen geometry using two commercial steels, AISI 4130 and AISI 4140, with the goal of transferring a verified methodology to the heat treatment process for industrial heavy-section products (bars, slabs). The simulation employs thermal, mechanical, and …

Critical Parameters Controlling Oxide Scale Formation And Hydro-Descaling Efficiency During Steelmaking, Tochukwu Princewill Ojiako

Doctoral Dissertations

In modern steelmaking, cast slabs are exposed to high-temperature oxidizing environments during secondary cooling, reheating, and hot rolling, resulting in the formation of multilayer oxide scales on the steel surface. These scales interact with mold-flux residues originating from the casting process (CC). The morphology, chemistry, and adhesion of oxide scale strongly influence its removability during high-pressure hydraulic descaling and ultimately determine the surface quality of hot-rolled products. However, the mechanistic relationship between oxide scale evolution, scale-steel interfacial structure, and hydraulic descaling performance remains poorly understood.

This dissertation investigates oxide scale formation, modification, and removal in low-carbon thin-slab steels produced by …

Castrip Process Technology: Non-Grain Oriented (Ngo) Si Steels Extension And Carbide-Free Bainitic (Cfb) For Flat Products, Naram Naidu Meesala

Masters Theses

"This research explores the development of advanced steel grades manufactured through Castrip® twin-roll thin strip casting technology, with particular attention to non-grain-oriented electrical Si-Steels (NGOES) and carbide-free bainitic (CFB) steels. The Castrip® process offers a near-net-shape route for producing thin steel strips, which greatly decreases the number of processing stages, lowers energy demand, and reduces carbon dioxide emissions when compared with traditional steel production methods.

In the NGOES part of the study, several industrial Fe–Si steel compositions were cold rolled to final thicknesses ranging from 0.35 mm to 0.15 mm. These materials were then exposed to short-duration continuous annealing at …

Compression Forming Of Basic Oxygen Furnace Slag-Gypsum Blocks: Performance Enhancement And Environmental Assessment, Fengyi Zhang

Student Works (2020-2029)

The construction industry plays a crucial role in global development but faces significant environmental challenges, particularly CO2 emissions from cement production. Gypsum blocks provide a sustainable alternative to traditional cement concrete blocks. However, the low mechanical strength and water resistance of gypsum materials limit the widespread adoption of gypsum-based materials in the construction industry. This study initially produced gypsum-based blocks using compression forming, adding supplementary cementitious materials (SCMs), and subjecting accelerated carbonation curing (ACC). It was found that compression forming addressed the shortcomings of traditional block manufacturing (high energy consumption and long production time), and the addition of SCMs generated …

Shaking Table Test And Numerical Simulation Of Seismic Response Characteristics Of Rock Slope With Muddy Interlayer, Duan Chenggang, Fang Yanlin, Tian Yeqing, Zhou Zhijun

Journal of China & Foreign Highway

In order to study the seismic macroscopic failure process and dynamic response characteristics of rock slope with muddy interlayer and reveal the influence of muddy interlayer on slope stability,a similar slope model with concave and convex slope types was designed,and shaking table test was carried out;finite element analysis was used for numerical modeling analysis,and the results obtained by the two models were compared.The results show that:① The macroscopic deformation and failure process of the model slope is divided into three stages.Muddy interlayer dislocates,and cracks occur;mud interlayer slips,and cracks expand;slope collapses;② The seismic load has a decisive influence on the stability …

Effect Of Lithium Slag Dosage On Strength And Dry Shrinkage Properties Of Cement Stabilized Recycled Macadam, Zhao Ziyu, Gan Xianyong

Journal of China & Foreign Highway

To improve the mechanical properties and dry shrinkage properties of cement stabilized bases formed by cold in-place recycling of cement concrete pavements,lithium slag was mixed into the recycled mixture in mass ratios of 0%,6%,9%,and 12%.The effects of lithium slag dosage on the mechanical,dry shrinkage,and water stability properties of the recycled base were analyzed through the unconfined compressive strength,splitting,dry shrinkage,and water stability tests,and the mechanism underlying the improving effect of lithium slag on the cement stabilized base formed by cold in-place recycling of the cement concrete pavement was analyzed by X-ray diffraction (XRD ) and scanning electron microscopy (SEM ).The results …

Optimization Of Infill Concrete Dimension In Composite Girder Box Based On Igrnn, Wang Yafeng, Liu Jian, Ke Hongjun

Journal of China & Foreign Highway

The mechanical performance of the negative bending moment zone of steel-concrete composite continuous girders has always been a focus of attention in bridge engineering.Existing research mainly proposes improvement measures for the tension of concrete bridge decks,while paying little attention to the common phenomenon of steel girders bearing pressure.The steel girders in steel-concrete composite girders,especially the steel bottom plate in the negative bending moment area of the pier top,bear the highest compressive stress of the entire bridge.Therefore,by taking a steel-concrete composite girder bridge in Zhejiang Province as the engineering background,it is proposed to partially fill the interior of the box girder …

Research On Cable Force Optimization Of Long-Span Cable-Stayed Bridges Based On Rbfnn+Improved Parti Cle Swarm Optimization Algorithm, Deng Da, He Bowen, Liu Guokun

Journal of China & Foreign Highway

In view of the cable force optimization problem of long-span cable-stayed bridges,a cable force optimization method considering the reliability index of stay cables was proposed based on the response surface fitted by the radial basis function neural network (RBFNN ).The RBFNN-based response surface model for solving the reliability index was established by fitting the structural implicit function through RBFNN training.The improved particle swarm optimization algorithm was used to search for the optimal solution of the cable force optimization model considering the reliability index.The research results show that RBFNN can accurately predict the structural responses and fit the structural implicit performance …

Design Optimization And Experimental Study Of Cfrp Plate Anchorage With Clip-Extension Type, Qi Yijia, Xiao Dan, Wang Zhongqiang

Journal of China & Foreign Highway

Existing anchorage is prone to damaging the carbon-fiber reinforced polymer (CFRP ) plate due to the “notch effect ” and uneven distribution of clamping stress.This study proposed a new clip-extension type anchorage for the CFRP plate.This design utilized the ductility of steel for stress diffusion and guided the compressive stress zone in the CFRP plate away from the notched end,realizing a smooth transition of the clamping force of the CFRP plate at the clip port and effectively reducing the “notch effect ”.The design also reduced the strain difference between the carbon fibers,resulting in a more synchronized lateral deformation of the …

Research And Applicat Ion Of Ultra Large-Scale Consolidated Under-Reamed Drilled Shaft Technology Under Special Environmental And Geological Conditions, Ding Yi, Yu Kun, Shi Haiyang, Pei Xiaofeng, Zhu Bo

Journal of China & Foreign Highway

This article aims to add ress the poor economic efficiency of large-diameter and ultra-long piles,the high risk of hole collapse in thick sandy soil,and the limited space across the canal faced by the Bridge over Yellow River Diversion to Qindao Canal on Zhanhua ‒ Linyi Expressway.According to the comparison of conventional drilled cast-in-place piles with combined pile-end and pile-side post-grouting,the industry ’s under-reamed drilled shaft foundation with the largest disc diameter (4.5 m) and the largest single-pile volume (456 m3) was proposed and designed.At the same time,supporting devices such as three-arm rotary cutting drill bits and long arm borehole diameter …

Analysis Of Influence Of Internal Erosion On Deformation Of Subway Station Structure, Qin Tianxin, Wang Chen, Tan Xuyan, Wei Shengming, Liang Fayun

Journal of China & Foreign Highway

Under the long-term effects of disasters such as rainstorms and floods,the soil layer around subway stations may be affected by internal erosion,threatening the structural safety of urban subway stations.To explore the influence of internal erosion on subway station structures,this study conducted isotropic consolidation and triaxial compression tests on gap-graded sand soil.Eroded soil specimens were simulated by adjusting the fine particle content to explore the pattern of variations in physical and mechanical properties caused by internal erosion.Results indicate that internal erosion alters the stress-strain relationship of gap-graded sand soil,increasing compressibility,decreasing shear strength,and weakening dilatancy.Drucker-Prager (DP) cap model parameters for eroded sand …