Civil and Environmental Engineering Commons^™

Strain And Temperature Measurement From Distributed Fiber Optic Sensors In Performance-Based Fire Engineering, Yanping Zhu

Doctoral Dissertations

"Strain and temperature measurement of steel and concrete structures under fires is critical to the understanding of structural performance yet historically challenging due to a significant gap in measurement science. This Ph.D. study characterizes in six parts low-cost distributed fiber optic sensors and applies them to strain, and temperature measurements based on Rayleigh and Brillouin light scattering. The first part aims to quantify the Rayleigh scattering based measurement accuracy of distributed fiber optic sensors under a heating-holding load protocol and characterize the effect of polymer coating on the sensors as the polymer softens and melts at elevated temperatures. The second …

Post-Seismic Response And Repair Of Earthquake-Damaged Reinforced Concrete Bridges, Giacomo Fraioli

Doctoral Dissertations

“In bridge structures, column members are typically designed to be the primary source of energy dissipation during an earthquake. Therefore, reinforced concrete (RC) bridges that are damaged in an earthquake tend to have damage to the column members. While many studies have been conducted on seismic strengthening of RC bridge columns, most are focused on retrofit instead of repair. In addition, the limited research on seismic repair of RC bridges has focused on evaluating the response of individual columns (member level), not the bridge structure (system level), due to limitations in modeling and especially testing of full bridge structures. Local …

Bcmnet: Cross-Layer Extraction Structure And Multiscale Downsampling Network With Bidirectional Transpose Fpn For Fast Detection Of Wildfire Smoke, Jiayong Li, Guoxiong Zhou, Aibin Chen, Chao Lu, Liujun Li

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

At present, the wildfire smoke detection algorithm based on YOLOv3 has problems, such as low accuracy and slow detection speed. In this article, we propose a cross-layer extraction structure and multiscale downsampling network with bidirectional transpose FPN (BCMNet) for fast detection of wildfire smoke. First, a cross-layer extraction module, which combines linear feature multiplexing and receptive field amplification, is designed. It can improve the speed and accuracy of wildfire smoke detection. Second, a multiscale downsampling module with different convolution kernels and maximum pooling operation is designed to preserve the details of the image while downsampling. Then, a bidirectional transposed FPN …

Parenting Pre-Teens During Covid-19 In A Rural Midwestern Community: An Interpretive Phenomenological Study, Sarah Oerther, Daniel B. Oerther

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

To uncover the experiences of parenting Generation Z pre-teen children in rural communities impacted by the Stay Home Missouri order from April through May 2020. Researchers have focused on urban parents, leading to gaps in understanding the impact of the COVID-19 quarantine on rural parents and children. A qualitative study employing interpretive phenomenology. 14 white cis-male-sexed fathers and cis-female-sexed mothers living in midwestern rural communities participated in this study. Semi-structured interviews with 14 participants parenting pre-teen children were conducted. The interviews were analyzed using interpretive phenomenology. The COREQ checklist was followed. One theme that emerged from the narratives was the …

Assessing Phenotypic Response Of Plants Irrigated With Municipal Solid Waste Landfill Leachate Using Computer Visualization, Rahel Pommerenke

Masters Theses

"Most solid waste collected in the US is disposed of in sanitary landfills, which have a lingering legacy of unintended negative impacts on the environment. Landfill design and operation are expensive, prone to multiple failure modes, and often do not address human and ecological risks presented by contaminants of emerging concern. A notable and common failure mechanism is leachate production. Moisture in the waste mixes with infiltrating water to form wastewater that must be collected and treated prior to discharge. Recycling leachate at landfills by recirculating it onto vegetated landfill covers relies on the evapotranspiration potential of plants to reduce …

Ecological Restoration Of Lead/Zinc/Copper Mine Tailings: Phytomanagement And Amendment Strategies To Enhance Substrate Functionality And Biomass Production, Mariam K. Al-Lami

Doctoral Dissertations

“The extreme physiochemical characteristics of mine tailings inhibit microbial processes and natural plant growth. Consequently, vast and numerous tailings sites remain barren for decades and highly susceptible to wind and water erosion. Phytostabilization is a cost-effective and ecologically productive remediation approach; however, tailings revegetation is generally challenging and must often be assisted with appropriate soil amendments. Amendments applied individually in greenhouse studies discussed herein revealed notable improvement in bioenergy crops growth only with biosolids treatments. Recalcitrant carbon amendments (biochar and humus) showed notable impact only on tailings physichochemical and hydraulic properties. Nevertheless, biosolids may not support sustained vegetation due to …

Characterization And Utilization Of Alkali-Activated Concrete For Sustainable Infrastructures, Eslam Gomaa

Doctoral Dissertations

“This study has investigated the feasibility of using locally available fly ashes (FAs) to synthesize alkali-activated concrete (AAC) for different structural and repair applications. Using AAC made of 100% FA reduces global CO2 emissions, saves energy, and decreases raw material consumption during the production process of ordinary Portland cement. Class C FAs, sourced from Labadie, Jeffery City, Kansas City, Thomas Hill, and Sikeston power plants in the state of Missouri, were used to synthesize the AAC. Sodium silicate (SS), Na2SiO3, and sodium hydroxide (SH), NaOH were used as the alkali activators. Slag, crumb rubber, and air-entraining admixture were used as …

A Three-Dimensional Fully Coupled Hydro-Mechanical Elasto-Plastic Model For Unsaturated Soils With Consideration Of Hysteresis Behavior, Beshoy Sami Moussa Riad

Doctoral Dissertations

"Unsaturated soils are often used as a construction material in transportation infrastructures; in which it is subjected to cyclic traffic loadings and/or seasonal wetting-drying cycles. While mechanical hysteresis is a common feature of soils in general, hydraulic hysteresis is associated with unsaturated soils. Most existing constitutive models paid limited attention to the mechanical and hydraulic hysteresis behavior of unsaturated soils. This research presents a three-dimensional model for unsaturated soils and a chemo mechanical model for saturated soils. The unsaturated soils’ model has the following characteristic features: (a) the hydraulic and mechanical behaviors are fully coupled under 3D conditions; (b) it …

Strategies To Improve Shrinkage Resistance Of Cement-Based Materials For Extrusion-Based 3d Printing, Kavya Vallurupalli

Doctoral Dissertations

"The main objective of this study is to develop new generation of shrinkage-resistant 3D printable mortar mixtures. To this end, the research work was carried out to: i) identify key material and processing parameters that affect printability; ii) investigate the influence of water-to-cement ratio, superplasticizer dosage, and welan gum content on mortar printability; iii) propose a “printability window” where rheological properties and desorptivity can secure successful printing; iv) investigate effect of shrinkage mitigation materials (expansive agent (EA), pre-saturated lightweight sand (LWS), superabsorbent polymers (SAP), and shrinkage reducing admixture) on printability and shrinkage performance of mortar; and v) evaluate the effect …

Design And Performance Of Self-Consolidating And Thixotropic Ultra-High-Performance Concrete For Infrastructure Construction And Rehabilitation, Le Teng

Doctoral Dissertations

"The objective of this research is to develop two classes of ultra-high-performance concrete (UHPC), one with self-consolidating consistency and the other with improved thixotropy. Tailoring the rheological properties of low yield stress UHPC can improve dispersion and orientation of steel fibers used in the design of UHPC, hence enhancing the tensile and flexural properties. Similarly, improving the thixotropy of UHPC can enable unique performance for the design of thin bonded bridge deck overlay. The research investigated various thixotropy enhancing admixtures to enhance the structural build-up at rest of UHPC. A total of 16 bonded overlay slab specimens were used to …

Investigating The Interaction Between The Recycled Components And The Asphalt Binders, Plant, Lab, And Field Mixes, Eslam Deef-Allah

Doctoral Dissertations

"Modifying asphalt binders and mixes with recycled components is common practice due to their environmental and economic merits. Literature has indicated that different recycled components interact with (blend with) asphalt differently, ranging from no blending, partial blending, or full blending. The degree of blending between recycled components and virgin asphalt binders (VABs) and the exchanged components impact the performance of modified asphalt binders. However, the nature of the interaction process between the recycled components and the VABs is not fully understood. The primary objective of this study was to explore the interactions between recycled components and VABs. By understanding the …

Theoretical Determination Of The Yield Curve For Unsaturated Soils, Sara Fayek

Doctoral Dissertations

"An important step to developing a good understanding of the behavior of unsaturated soils is to adopt a formal and simple constitutive framework and to conduct high-quality and short-time experiments. Barcelona Basic Model (BBM) was the first elastoplastic constitutive model for unsaturated soils. The yield curve, which separates the elastic region from the elastoplastic region, is an important aspect of constitutive modeling for unsaturated soils. Most concepts for unsaturated soils were developed based upon the results from suction-controlled triaxial (SCTX) tests. Though, the SCTX tests on unsaturated soils are costly, time-consuming, and laborious, and their results are questionable. This study …

Promoting Distributed Energy Deployment And Diffusion For Sustainable Civil Infrastructure Using Multi-Agent Based Modeling And Quantitative Analytics, Gasser Ali

Doctoral Dissertations

"Distributed Solar Generation (DSG) using small-scale Photo-Voltaic (PV) is an evolving technology with increasingly growing market penetration due to its significant benefits to consumers and broader power systems. DSG is sustainable, provides reliability, and is cost-effective where solar energy is abundant. However, the increasingly growing adoption of DSG creates uncertainties in forecasting electric power demand and market behavior. It also causes concerns of a “utility death spiral”. To this end, the goal of this research is to critically analyze the diffusion and benefits of DSG in the electric power infrastructure as a complex System-of-Systems (SoS). Specifically, this dissertation addresses the …

Corrosion Resistance Performance Investigation Of Mild Steel Bar Coated With Magnesium Phosphate Cement Paste, Fan Zhang

Doctoral Dissertations

"In this research study, the anti-corrosion mechanism of reinforcement embedded in magnesium potassium phosphate cement (MKPC) is explored. In addition, one type of additives, metakaolin, and one type of retarder, boric acid, are employed in MKPC to modify its properties in order to further investigate corrosion resistance and to achieve mass-production coating reinforcement at the work site. This coating method may be practical for some underwater construction and some traditional reinforcement concrete structures to reduce the reinforcement corrosion rate and to eventually extend service life in both repair and new construction applications.

By comparing the electrochemical properties of bare ribbed …

Multifunctional Behaviors Of Two-Dimensional Materials And Their Composites, Yanxiao Li

Doctoral Dissertations

"Two-dimensional (2D) materials, including graphene, transition metal carbides or nitrides (TMC/Ns), have rich surface chemistry, superb electrical and mechanical properties. These unique properties make them ideal for multifunctional devices. Among them, we focused on graphene and TMC/Ns (i.e., MXenes), as well as their composites. Unlike the well-known graphene, MXenes, are relatively new and typically synthesized by the selective etching of the “A” layers from the layered carbides and /or nitrides known as MAX phases, which introduce MXenes with rich terminal groups (e.g. -O-, -OH, -F).

During my Ph.D. study, firstly, the adhesive and frictional behaviors, which are related to successful …

Tension-Stiffening Effect Consideration For Modeling Deflection Of Cracked Reinforced Uhpc Beams, Le Teng, Rongling Zhang, Kamal Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Tension-stiffening effects can significantly influence the flexural performance of cracked reinforced concrete specimens. Such effect is amplified for fiber-reinforced concrete, given the fact that fibers can bridge the cracks. The objective of this study was to develop a model to predict the deflection of cracked reinforced ultra-high performance concrete (R-UHPC) beam elements. The modeling approach characterized the average bending moment of inertia by combining the existing model used for conventional reinforced concrete and the analytical model of stress distribution of UHPC along the cross-section. The finite element analysis (FEA) was employed to evaluate the flexural deflection based on the average …

Optimizing Exterior Lighting Illuminance And Spectrum For Human, Environmental, And Economic Factors., S. M. Simmons, Stuart Werner Baur, William L. Gillis, Devin Michael Burns, Heath Pickerill

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

With the recent widespread adoption of LED lighting in outdoor areas, numerous concerns have been raised about the potential for harmful effects on humans, animals, plants, and the night sky. These stem from the high blue light content of some LED bulbs and an incentive to increase lighting levels caused by higher efficiency and lower costs. While new lighting installations are often described as environmentally friendly due to their energy efficiency, factors such as light pollution are often neglected or not given enough weight. This research focuses on optimizing the design of exterior lighting for human, environmental, and economic factors …

Innovative Approach To Use Guayule Resin As A Bio-Based Asphalt Alternative, Ahmed Hemida

Doctoral Dissertations

"Asphalt cement will not last long as the world encounters a diminishment in crude oil. Novel resources can contribute to replacing asphalt with the sustainable, flexible pavement. This study presented guayule resin (guayule) as an innovative bio-based asphalt alternative. Ground tire rubber was used as an asphalt enhancer. To judge the guayule's contribution, guayule-based binders were investigated and compared to control asphalt and asphalt-rubber binders. Binders were assessed according to comprehensive Superpave criteria and advanced rheological tests. Component analysis was performed to link the microscale level with the macroscale level. To validate the novel binder, satisfying mix performance tests were …

Use Of Cellular Concrete For Air Convection Embankment To Protect Permafrost Foundation In Cold Regions, Hanli Wu

Doctoral Dissertations

"Crushed-rock air convection embankment (ACE) has been used to mitigate thaw settlement, and pavement distresses caused by climatic extremes in permafrost regions for over three decades. However, the desired crushed rocks needed for ACE are not readily available in many areas of interior Alaska. Burdened by the need to ship suitable rocks to remote locations, the cost of constructing an ACE is often prohibitively high, which prevents its wide use in Alaska. An existing cementitious material, cellular concrete, may provide the solution.

This study intends to systematically characterize the heat transfer patterns of ACE and identify the performance benefits of …

Synergistic Effect Of Shrinkage Mitigating Strategies On Performance Of Fiber-Reinforced Cementitious Composites, Kamran Aghaee

Doctoral Dissertations

"The advantages of using shrinkage mitigating strategies to reduce shrinkage and mitigate cracking of concrete is well documented. However, the benefits and drawbacks of employing multiple strategies have not been explored. The main objective of this study is to provide insights into the mechanisms of using multiple strategies to enhance shrinkage and cracking resistance to promote the properties of high-performance cementitious composites (HPC) designated for infrastructural construction, repair, and 3D printing applications. HPC mixtures were prepared with steel and synthetic macro and microfibers, expansive agent (EA), and shrinkage reducing admixture (SRA) coupled with various curing methods e.g., internal curing using …

Deep Learning-Based Surrogate Models For Post-Earthquake Damage Assessment, Xinzhe Yuan

Doctoral Dissertations

"Seismic damage assessment is a critical step to enhance community resilience in the wake of an earthquake. This study aims to develop deep learning-based surrogate models for widely used fragility curves to achieve more accurate and rapid assessment in practice. These surrogate models are based on artificial neural networks trained from the labelled ground motions whose resulting damage classes on targeted structures are determined by nonlinear time history analyses. The development of various surrogate models is progressed in four phases. In Phase I, the multilayer perceptron (MLP) is used to develop multivariate seismic classifiers with up to 50 hand-crafted intensity …

Durable Nanocomposite Face Masks With High Particulate Filtration And Rapid Inactivation Of Coronaviruses, Andrew Gonzalez, Hamada A. Aboubakr, John Brockgreitens, Weixing Hao, Yang Wang, Sagar M. Goyal, Abdennour Abbas

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The COVID-19 pandemic presents a unique challenge to the healthcare community due to the high infectivity rate and need for effective personal protective equipment. Zinc oxide nanoparticles have shown promising antimicrobial properties and are recognized as a safe additive in many food and cosmetic products. This work presents a novel nanocomposite synthesis approach, which allows zinc oxide nanoparticles to be grown within textile and face mask materials, including melt-blown polypropylene and nylon-cotton. The resulting nanocomposite achieves greater than 3 log₁₀ reduction (≥ 99.9%) in coronavirus titer within a contact time of 10 min, by disintegrating the viral envelope. The …

Editorial: Molecular Simulation On Cementitious Materials: From Computational Chemistry Method To Application, Hongyan Ma, Dongshuai Hou, Jinrui Zhang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

No abstract provided.

Hyperspectral Imaging And Data Analytics For Civil Infrastructure Inspection, Genda Chen

INSPIRE Archived Webinars

In this 50-minute lecture, the fundamental concept of hyperspectral imaging is reviewed. Each hyperspectral image represents a narrow, contiguous wavelength range of an electromagnetic spectrum, which could be indicative of a chemical substance. All the images in the spectral range of a hyperspectral camera are combined to form a three-dimensional hyperspectral data cube with two spatial dimensions and one spectral dimension. A hyperspectral cube can be sampled in four ways: spatial scanning, spectral scanning, snapshot imaging, and spatio-spectral scanning. This presentation will be focused on spatial scanning from a line-scan camera. The feasibility of horizontal imaging from a synchronized hyperspectral …

Orchestrating Performance Of Healthcare Networks Subjected To The Compound Events Of Natural Disasters And Pandemic, Emad M. Hassan, Hussam N. Mahmoud

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The current COVID-19 pandemic has demonstrated the vulnerability of healthcare systems worldwide. When combined with natural disasters, pandemics can further strain an already exhausted healthcare system. To date, frameworks for quantifying the collective effect of the two events on hospitals are nonexistent. Moreover, analytical methods for capturing the dynamic spatiotemporal variability in capacity and demand of the healthcare system posed by different stressors are lacking. Here, we investigate the combined impact of wildfire and pandemic on a network of hospitals. We combine wildfire data with varying courses of the spread of COVID-19 to evaluate the effectiveness of different strategies for …

Healthcare And Education Networks Interaction As An Indicator Of Social Services Stability Following Natural Disasters, Emad M. Hassan, Hussam Mahmoud

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Healthcare and education systems have been identified by various national and international organizations as the main pillars of communities' stability. Understanding the correlation between these main social services institutions is critical to determining the tipping point of communities following natural disasters. Despite being defined as social services stability indicators, to date, no studies have been conducted to determine the level of interdependence between schools and hospitals and their collective influence on their recoveries following extreme events. In this study, we devise an agent-based model to investigate the complex interaction between healthcare and education networks and their overall recovery, while considering …

Multi-Scale Hydrologic Evaluation Of The National Water Model Streamflow Data Assimilation, Bong Chul Seo, Witold F. Krajewski, Felipe Quintero

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Streamflow predictions derived from a hydrologic model are subjected to many sources of errors, including uncertainties in meteorological inputs, representation of physical processes, and model parameters. To reduce the effects of these uncertainties and thus improve the accuracy of model prediction, the United States (U.S.) National Water Model (NWM) incorporates streamflow observations in the modeling framework and updates model-simulated values using the observed ones. This updating procedure is called streamflow data assimilation (DA). This study evaluates the prediction performance of streamflow DA realized in the NWM. We implemented the model using WRF-Hydro® with the NWM modeling elements and assimilated 15-min …

The Bridge Newsletter Winter 2021, Missouri University Of Science And Technology

The Bridge Newsletter

-S&T contributes to infrastructure through national center
-Brinkmann leads Missouri Highways and Transportation Commission
-Wu wins NSF CAREER Award for 2D metals work
-Academy of Civil Engineers induction and 150^th celebration

Naturally Occurring Van Der Waals Heterostructure Lengenbachite With Strong In-Plane Structural And Optical Anisotropy, Arindam Dasgupta, Xiaodong Yang, Jie Gao

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Lengenbachite is a naturally occurring layered mineral formed with alternating stacks of two constituent PbS-like and M₂S₃-like two-dimensional (2D) material layers due to the phase segregation process during the formation. Here, we demonstrate to achieve van der Waals (vdW) heterostructures of lengenbachite down to a few layer-pair thickness by mechanical exfoliation of bulk lengenbachite mineral. The incommensurability between the constituent isotropic 2D material layers makes the formed vdW heterostructure exhibit strong in-plane structural anisotropy, which leads to highly anisotropic optical responses in lengenbachite thin flakes, including anisotropic Raman scattering, linear dichroism, and anisotropic third-harmonic generation. Moreover, …

Faster Post-Earthquake Damage Assessment Based On 1d Convolutional Neural Networks, Xinzhe Yuan, Dustin Tanksley, Liujun Li, Haibin Zhang, Genda Chen, Donald C. Wunsch

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Contemporary deep learning approaches for post-earthquake damage assessments based on 2D convolutional neural networks (CNNs) require encoding of ground motion records to transform their inherent 1D time series to 2D images, thus requiring high computing time and resources. This study develops a 1D CNN model to avoid the costly 2D image encoding. The 1D CNN model is compared with a 2D CNN model with wavelet transform encoding and a feedforward neural network (FNN) model to evaluate prediction performance and computational efficiency. A case study of a benchmark reinforced concrete (r/c) building indicated that the 1D CNN model achieved a prediction …