Civil and Environmental Engineering Commons^™

The Prospect Of Microwave Heating: Towards A Faster And Deeper Crack Healing In Asphalt Pavement, Shi Xu, Xueyan Liu, Amir Tabakovic, Erik Schlangen

Articles

Microwave heating has been shown to be an effective method of heating asphalt concrete and in turn healing the damage. As such, microwave heating holds great potential in rapid (1–3 min) and effective damage healing, resulting in improvement in the service life, safety, and sustainability of asphalt pavement. This study focused on the microwave healing effect on porous asphalt concrete. Steel wool fibres were incorporated into porous asphalt to improve the microwave heating efficiency, and the optimum microwave heating time was determined. Afterwards, the microwave healing efficiency was evaluated using a semi–circular bending and healing programme. The results show that …

Possibilities Of Using Silicate Rock Powder: An Overview, Claudete Gindri Ramos, James C. Hower, Erika Blanco, Marcos Leandro Silva Oliveira, Suzi Huff Theodoro

Center for Applied Energy Research Faculty and Staff Publications

This study evaluates the on use of crushed rocks (remineralizers) to increase soil fertility levels and which contributed to increase agricultural productivity, recovery of degraded areas, decontamination of water, and carbon sequestration. The use of these geological materials is part of the assumptions of rock technology and, indirectly, facilitates the achievement of sustainable development goals related to soil management, climate change, and the preservation of water resources. Research over the past 50 years on silicate rocks focused on soil fertility management and agricultural productivity. More recently, the combined use with microorganisms and organic correctives have shown positive results to mitigate …

Mechanical Characteristics Of Cement Paste In The Presence Of Carbon Nanotubes And Silica Oxide Nanoparticles: An Experimental Study, Moses Karakouzian, Visar Farhangi, Marzieh R. Farani, Alireza Joshaghani, Mehdi Zadehmohamad, Mohammad Ahmadzadeh

Civil and Environmental Engineering and Construction Faculty Research

Considering the remarkable characteristics of nanomaterials, previous research studies investigated the effects of incorporating different types of these materials on improving the concrete properties. However, further studies are required to evaluate the complementary hybridization and synergistic influence of nanomaterials. In this research, the combined effect of adding nano silica particles (NS) and multi-walled carbon nanotubes (MWCNT) on enhancing both the compressive and flexural strengths of the cement paste was investigated. Moreover, the morphology of the interface between cement paste and aggregates was studied by scanning electron microscopy (SEM). The mixtures were prepared using three different portions of MWCNT and NS. …

Engineering Students’ Perceptions Of Mathematical Modeling In A Learning Module Centered On A Hydrologic Design Case Study, Madeline F. Merck, Melissa A. Gallagher, Emad Habib, David G. Tarboton

Civil and Environmental Engineering Faculty Publications

Engineering students need to spend time engaging in mathematical modeling tasks to reinforce their learning of mathematics through its application to authentic problems and real world design situations. Technological tools and resources can support this kind of learning engagement. We produced an online module that develops students‚Äô mathematical modeling skills while developing knowledge of the fundamentals of rainfall-runoff processes and engineering design. This study examined how 251 students at two United States universities perceived mathematical modeling as implemented through the online module over a 5-year period. We found, subject to the limitation that these are perceptions from not all students, …

The Effect Of Cement And Blast Furnace Slag Characteristics On Expansion Of Heat-Cured Mortar Specimens, Jair G. Burgos

USF Tampa Graduate Theses and Dissertations

Delayed ettringite formation (DEF) is a durability issue that typically occurs in concrete exposed to high temperatures at an early age such as precast elements and massive concrete structural elements. There are many advantages to precast concrete such as its quality control, better safety control, and reusable forms, which make them cheaper than casting on site [1]. Heat curing of precast concrete is conducted to obtain high early-strength. However, in doing so, durability issues can arise in the form of internal sulfate attack also known as DEF, if the internal temperature of concrete exceeds 70°C. Past this threshold, ettringite decomposes …

An Analysis Of Suspended Sediment Dynamics In A Partially Mixed Estuary, Riyadh Hamad Muttaleb

Dissertations and Theses

The purpose of this work is to investigate via data analysis and numerical modeling the SPM (suspended particulate matter) dynamics of a heavily contaminated partially urban estuary, the Lower Passaic River estuary (LPR), NJ. Accordingly, I investigate the quantity and mechanics of variation of fine and coarse SPM in the LPR via data analysis. Data analysis focuses on the parameters that affect SPM dynamics at six moored stations occupied during the Fall and Spring seasons, from near the estuary mouth to tidal freshwater. A 3D hydrodynamic model (Delft3D-FM) is used to analyze the effects of estuary topography on the dynamic …

Developing A Cost Of Delay (Cod) Framework For The Dod & Analyzing The Current State Of Air Force Agile Cost Estimation, James Goljan

Theses and Dissertations

The study has two research objectives. The first research objective develops a proof of concept for a Cost of Delay (CoD) framework to evaluate the Air Forces Kessel Run Software Factory. CoD provides a means to justify and prioritize competing interests regarding budgetary, manpower, and overall strategic decisions. DoD organizations can employ a cost minimization framework to conduct CoD Analysis. The results demonstrate Software Factories eschew trends in the literature towards more complicated cost models that incorporate machine learning with Data-Based techniques in lieu of simpler models that utilize Engineering Build-up Capacity Based techniques.

Applications Of Biomimicry In Construction And Architecture: A Bibliometric Analysis, Mugdha Praveen Kshirsagar Mrs, Sanjay Kantrao Kulkarni Dr, Ankush Kumar Meena Mr, Danby Caetano D’Costa Mr, Sushant Sunil Bhavsar Mr

Library Philosophy and Practice (e-journal)

Biomimicry can be considered to be a way of connecting the environment created by man to the natural world. Biomimicry is a science that, as a model, a measure and a tutor, looks to nature. Via site work, construction and everyday operations, biomimicry can be used to enhance the way the built environment is constructed. The main objective of this paper is to perform a bibliometric study of biomimicry-related literature in order to discover the growth of biomimicry as an architectural method in recent years. The time frame considered for this survey is between 1990 and 2020. The findings, however, …

A Hermeneutic Phenomenological Study Into The Impact Of Bim On The Social Dynamics Of The Aec Professional In The Workplace., Malachy Mathews Dr.

Doctoral

A review of the literature published surrounding new digital design and construction technologies and associated processes described within the Architecture, Engineering, and Construction (AEC) community as Building Information Modelling (BIM) or Virtual Design and Construction (VDC) reveals a gap in the theoretical understanding of the impact these technologies are having on professionals who work in this industry. The central aim of this research is to discover if there has been a shift in social dynamics as a result of the adoption of BIM in the workplace and, if there has been, to discuss the meaning of this for the industry …

Weather-Related Construction Delays In A Changing Climate: A Systematic State-Of-The-Art Review, Steven J. Schuldt, Matthew R. Nicholson, Yaquarri A. Adams Ii, Justin D. Delorit

Faculty Publications

Adverse weather delays forty-five percent of construction projects worldwide, costing project owners and contractors billions of dollars in additional expenses and lost revenue each year. Additionally, changes in climate are expected to increase the frequency and intensity of weather conditions that cause these construction delays. Researchers have investigated the effect of weather on several aspects of construction. Still, no previous study comprehensively (1) identifies and quantifies the risks weather imposes on construction projects, (2) categorizes modeling and simulation approaches developed, and (3) summarizes mitigation strategies and adaptation techniques to provide best management practices for the construction industry. This paper accomplishes …

Evolving Tides Aggravate Nuisance Flooding Along The U.S. Coastline., Sida Li, Thomas Wahl, Stefan A. Talke, David A. Jay, Philip M. Orton, Xinghui Liang, Guocheng Wang, Lintao Liu

Civil and Environmental Engineering Faculty Publications and Presentations

Nuisance flooding (NF) is defined as minor, nondestructive flooding that causes substantial, accumulating socioeconomic impacts to coastal communities. While sea-level rise is the main driver for the observed increase in NF events in the United States, we show here that secular changes in tides also contribute. An analysis of 40 tidal gauge records from U.S. coasts finds that, at 18 locations, NF increased due to tidal amplification, while decreases in tidal range suppressed NF at 11 locations. Estuaries show the largest changes in NF attributable to tide changes, and these can often be traced to anthropogenic alterations. Limited long-term measurements …

Comparative Study Of Human Pluripotent Stem Cell-Derived Endothelial Cells In Hydrogel-Based Culture Systems, Zhanqi Wang, Fuxing Zuo, Qing Liu, Xuesheng Wu, Qian Du, Yuguo Lei, Zhangmin Wu, Haishuang Lin

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Human pluripotent stem cell (hPSC)-derived endothelial cells (ECs) are promising cell sources for drug discovery, tissue engineering, and studying or treating vascular diseases. However, hPSC-ECs derived from different culture methods display different phenotypes. Herein, we made a detailed comparative study of hPSC-ECs from three different culture systems (e.g., 2D, 3D PNIPAAm-PEG hydrogel, and 3D alginate hydrogel cultures) based on our previous reports. We expanded hPSCs and differentiated them into ECs in three culture systems. Both 3D hydrogel systems could mimic an in vivo physiologically relevant microenvironment to protect cells from shear force and prevent cell agglomeration, leading to a high …

Development Of Design Tables For The Cold-Formed Steel Cross-Sections In Aisi D100, Committee On Specifications For The Design Of Cold-Formed Steel Structural Members

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

This report with the tables in an Excel file intends to provide the local and distortional buckling strengths for the cross-sections provided in AISI Cold-Formed Steel Design Manual to aid design engineers.

Development Of Cufsm Hole Module And Design Tables For The Cold-Formed Steel Cross-Sections With Typical Web Holes In Aisi D100, Committee On Specifications For The Design Of Cold-Formed Steel Structural Members

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

This report summarizes the effort to develop a simple hole module to perform elastic buckling analysis to obtain the design parameters needed for DSM considering the influence of holes. The hole module requires simple inputs and direct outputs of the elastic buckling information of the local and distortional buckling modes for both gross sections and sections with hole influences.

Review Of Testing By Analysis For Potential Implementation Into Aisi Standards, Committee On Specifications For The Design Of Cold-Formed Steel Structural Members

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

New product development is crucial to allow innovation in the cold-formed steel structural industry. However, the required physical testing of new components and assemblies are often a cost barrier which prevents implementation and slows new product development. Testing by analysis can be a good alternative to physical testing as it reduces the expense and time for performing physical experiments, however, two considerations are necessary to ensure accurate results. First, it requires a rational engineering analysis to calculate the capacities and deformations of the system, and the requirements to produce accurate analyses must be explicitly stated. Second, it is necessary to …

Steel Diaphragm Innovation Initiative, Year 5, Final Report, American Iron And Steel Institute

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

Summary

The Steel Diaphragm Innovation Initiative (SDII) is a multi-year industry-academic-government partnership to advance the seismic performance of steel floor and roof diaphragms utilized in steel buildings. This report provides a final report for Year 5 of the overall 5-year SDII plan. Contributions in the final 12 months (1 Jan. 2020 – 31 Dec. 2020) include the following highlights.

Innovation and Practice:

• Adoption in ASCE 7 of new provisions for bare steel deck including methods for buildings with rigid walls and flexible diaphragms, alternative diaphragm design with R_s, and special seismic detailing (following on from successful adoption in …

Tutorials For Mastan 2 And Related Validation, Committee On Specifications For The Design Of Cold-Formed Steel Structural Members

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

This report creates the tutorials helping engineers to correctly model and analyze structural systems comprised of non-doubly symmetric sections using the latest version of MASTAN2. The report also validated a MASTAN2 model using non-doubly symmetric sections against results from a small test program. The following report and tutorials are provided:

AISI Small Project Summary – Tutorials for MASTAN2 and Related Validation

• Tutorial for MASTAN2 v5.1 - Introductory Frame
• Tutorial for MASTAN2 v5.1 - Pour Stop Beam
• Tutorial for MASTAN2 v5.1 - Steel Joist

Machine Learning Methods To Map Stabilizer Effectiveness Based On Common Soil Properties, Amit Gajurel, Bhaskar Chittoori, Partha Sarathi Mukherjee, Mojtaba Sadegh

Civil Engineering Faculty Publications and Presentations

Most chemical stabilization guidelines for subgrade/base use unconfined compressive strength (UCS) of treated soils as the primary acceptance criteria for selecting optimum stabilizer in laboratory testing. Establishing optimal additive content to augment UCS involves a resource-intensive trial-and-error procedure. Also, samples collected from discrete locations for laboratory trials may not be representative of the overall site. This study aims to minimize the number of laboratory trials and help strategize sampling locations by developing spatial maps of UCS at different treatment levels for lime and cement. These spatial maps were developed using machine-learning techniques, and using a database compiled from various reported …

Initial Project Estimates For Design, Right Of Way, Utilities, And Construction, Christopher Van Dyke, Bryan Gibson, Jeff Jasper, Bob Lewis, Doug Kreis

Kentucky Transportation Center Research Report

Estimating the cost of highway construction projects is among the more challenging tasks state transportation agencies routinely deal with. Developing accurate estimates is a particularly fraught exercise during the planning and scoping phases, when projects have not been thoroughly defined and information on specifics is in short supply. While the Kentucky Transportation Cabinet (KYTC) has used several methodologies to generate initial cost estimates for design, right of way, utilities, and construction (DRUC), approaches vary between the agency’s districts. This report proposes a framework for estimating DRUC-related expenses that can be adopted throughout the state. Kentucky Transportation Center (KTC) researchers developed …

Quantitative Evaluation Of Asphalt Binder Extraction From Hot Mix Asphalt Pavement Using Ashing And Centrifuge Methods, Ahmed Hemida, Magdy Abdelrahman, Eslam Deef-Allah

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Asphalt binder requires more investigation to be accurately and precisely extracted since it is an effective procedure for quality assurance quality control (QA/QC) and subsequent binder characterization. In this research, the authors presented a hands-on experience with binder extraction to deliver recommendations concerning the sensitive steps that may affect the outcomes (extracted binder content, P_be%). Two mineral matter determination methods (ashing and centrifuge) were addressed based on the centrifuge extraction method. Field cores were investigated by comparing the P_be% to the actual binder content, P_ba%. Analysis of variance (ANOVA) and Tukey Post-Hoc statistical analyses, …

Impact Of Multiple Waves Of Covid-19 On Healthcare Networks In The United States, Emad M. Hassan, Hussam N. Mahmoud

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The risk of overwhelming hospitals from multiple waves of COVID-19 is yet to be quantified. Here, we investigate the impact of different scenarios of releasing strong measures implemented around the U.S. on COVID-19 hospitalized cases and the risk of overwhelming the hospitals while considering resources at the county level. We show that multiple waves might cause an unprecedented impact on the hospitals if an increasing number of the population becomes susceptible and/or if the various protective measures are discontinued. Furthermore, we explore the ability of different mitigation strategies in providing considerable relief to hospitals. The results can help planners, policymakers, …

Volcanic Emissions And Atmospheric Pollution: A Study Of Nanoparticles, Erika M. Trejos, Luis F. O. Silva, James C. Hower, Eriko M. M. Flores, Carlos Mario González, Jorge E. Pachón, Beatriz H. Aristizábal

Center for Applied Energy Research Faculty and Staff Publications

The influence of emissions of an active volcano on the composition of nanoparticles and ultrafine road dust was identified in an urban area of the Andes. Although many cities are close to active volcanoes, few studies have evaluated their influence in road dust composition. Air quality in urban areas is significantly affected by non-exhaust emissions (e.g. road dust, brake wear, tire wear), however, natural sources such as volcanoes also impact the chemical composition of the particles. In this study, elements from volcanic emissions such as Si > Al > Fe > Ca > K > Mg, and Si—Al with K were identified as complex hydrates. …

Accelerated Controller Tuning For Wind Turbines Under Multiple Hazards, Aly Mousaad Aly, Milad Rezaee

Faculty Publications

During their lifecycle, wind turbines can be subjected to multiple hazard loads, such as high-intensity wind, earthquake, wave, and mechanical unbalance. Excessive vibrations, due to these loads, can have detrimental effects on energy production, structural lifecycle, and the initial cost of wind turbines. Vibration control by various means, such as passive, active, and semi-active control systems provide crucial solutions to these issues. We developed a novel control theory that enables semi-active controller tuning under the complex structural behavior and inherent system nonlinearity. The proposed theory enables the evaluation of semi-active controllers’ performance of multi-degrees-of-freedom systems, without the need for time-consuming …

Non-Nuclear Methods For Compaction Control Of Unbound Soil And Granular Layers, Brad Rister, Charlie Sun, Kean H. Ashurst Jr., Tim Jones, Christopher Van Dyke

Kentucky Transportation Center Research Report

In highway construction, the nuclear density gauge (NDG) is the industry standard for measuring soil density and moisture. They are widely used at state transportation agencies, however, because of their reliance on radiation, NDGs are expensive to maintain and have unique storage requirements. Operators must also earn specialized certifications and adhere to rigorous safety protocols. Equipment manufacturers have developed several non-nuclear density gauges which are more user friendly, however, their accuracy has sometimes not equaled NDGs. This comparative study evaluated the performance of the eGauge (a relatively new device) to NDGs. Over 100 soil density and moisture measurements were collected …

Low-Cost Modal Identification Sensors For Bridge Field Testing, Daniel Linzell, Saaed Eftekhar Azam, Samira Ardani, Ahmed E Rageh

Nebraska Department of Transportation: Research Reports

This report provides a framework for experimental load rating of bridges via inclusion of low-cost dynamic sensors and dynamic tests. Currently 25% of the bridges in Nebraska are posted for live load. According to the National Bridge Inventory (NBI) in 2012, 93% of all postings in the US were based analytical load ratings, 7% were posted using field evaluation and engineering judgement, and 1% were posted using experimental load rating methods.

Instrumentation costs and traffic interruptions can be problematic when load testing is necessary to accurately assess in-situ bridge live load capacity. Recent advances in (i) sensing technology and (ii) …

A Comparison Of Porphyrin Photosensitizers In Photodynamic Inactivation Of Rna And Dna Bacteriophages, Joe Heffron, Matthew Bork, Brooke K. Mayer, Troy Skwor

Civil and Environmental Engineering Faculty Research and Publications

Effective broad-spectrum antiviral treatments are in dire need as disinfectants and therapeutic alternatives. One such method of disinfection is photodynamic inactivation, which involves the production of reactive oxygen species from dissolved oxygen in response to light-stimulated photosensitizers. This study evaluated the efficacy of functionalized porphyrin compounds for photodynamic inactivation of bacteriophages as human virus surrogates. A blue-light light emitting diode (LED) lamp was used to activate porphyrin compounds in aqueous solution (phosphate buffer). The DNA bacteriophages ΦX174 and P22 were more resistant to porphyrin TMPyP photodynamic inactivation than RNA bacteriophage fr, with increasing rates of inactivation in the order: ΦX174 …

Spectral Induced Polarization Study On Enzyme Induced Carbonate Precipitations: Influences Of Size And Content On Stiffness Of A Fine Sand, Bate Bate, Junnan Cao, Chi Zhang, Na Hao

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Heterogeneity in either chemically or microbiologically induced carbonate-based ground improvement methods is a major obstacle in engineering application. Spectral induced polarization (SIP), an innovative and nondestructive method, which has demonstrated promise in monitoring microbial activity, was used in this study to monitor enzyme induced carbonate precipitation (EICP). The complex conductivities, together with the shear wave velocities (Vs), of an EICP modified sand were monitored using a self-developed spectral induced polarization–bender element column. The mean precipitate size was calculated by relaxation time (τ) and the Schwarz equation. The precipitate contents were calculated by cumulative gamma distribution function on the global polarization …

Application Of Short-Time Stochastic Subspace Identification To Estimate Bridge Frequencies From A Traversing Vehicle, Nan Jin, Y. B. Yang, Elias G. Dimitrakopoulos, Themelina S. Paraskeva, Lambros S. Katafygiotis

Research outputs 2014 to 2021

This study establishes a short-time stochastic subspace identification (ST-SSI) framework to estimate bridge frequencies by processing the dynamic response of a traversing vehicle. The formulation uses a dimensionless description of the response that simplifies the vehicle-bridge interaction (VBI) problem and brings forward the minimum number of parameters required for the identification. With the aid of the dimensionless parameters the analysis manages to successfully apply ST-SSI despite the time-varying nature of the VBI system. Further, the proposed approach eliminates the adverse effect of the road surface roughness using a transformed residual vehicle response obtained from two traverses of a vehicle at …

Los Angeles Homeless Epidemic - An Analysis Of Proposition Hhh, Howard T. Duong

Construction Management

Passed in 2016, Proposition HHH is a $1.2 billion bill hoping to curb the homelessness epidemic that is rising in the city of Los Angeles with the newly added construction of 10,000 supportive housing units. This study serves to analyze and detail the homelessness epidemic in the Los Angeles Area, familiarizes the reader with how Proposition HHH funding works together with developers, as well as some of its shortcomings to date so far. To garner additional research, a survey was performed with a sample size from both the developers engaged with Proposition HHH and residents of the product in order …

Field Welding Repair Of Heavy Equipment, Phil Akahori

Construction Management

Welding repairs of heavy equipment in the field can vary in levels of success. This can be due to the high strength steels used in the manufacture of heavy equipment implements that require special metallurgical considerations. Repair difficulties can be further compounded by the limitations of tooling typically found on a construction site and schedule commitments. Overloading or excessive impacts can cause damage to the bucket teeth of an excavator or bulldozer rippers. A shop could perform a proper repair but that increases cost and takes precious time. A successful repair of these items done out in the field can …