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Abounia Omran, BehzadApplication of Data Mining and Big Data Analytics in the Construction Industry
Doctor of Philosophy, The Ohio State University, 2016, Food, Agricultural and Biological Engineering
In recent years, the digital world has experienced an explosion in the magnitude of data being captured and recorded in various industry fields. Accordingly, big data management has emerged to analyze and extract value out of the collected data. The traditional construction industry is also experiencing an increase in data generation and storage. However, its potential and ability for adopting big data techniques have not been adequately studied. This research investigates the trends of utilizing big data techniques in the construction research community, which eventually will impact construction practice. For this purpose, the application of 26 popular big data analysis techniques in six different construction research areas (represented by 30 prestigious construction journals) was reviewed. Trends, applications, and their associations in each of the six research areas were analyzed. Then, a more in-depth analysis was performed for two of the research areas including construction project management and computation and analytics in construction to map the associations and trends between different construction research subjects and selected analytical techniques. In the next step, the results from trend and subject analysis were used to identify a promising technique, Artificial Neural Network (ANN), for studying two construction-related subjects, including prediction of concrete properties and prediction of soil erosion quantity in highway slopes. This research also compared the performance and applicability of ANN against eight predictive modeling techniques commonly used by other industries in predicting the compressive strength of environmentally friendly concrete. The results of this research provide a comprehensive analysis of the current status of applying big data analytics techniques in construction research, including trends, frequencies, and usage distribution in six different construction-related research areas, and demonstrate the applicability and performance level of selected data analytics techniques with an emphasis on ANN in construction-related studies. The main purpose of this dissertation was to help practitioners and researchers identify a suitable and applicable data analytics technique for their specific construction/research issue(s) or to provide insights into potential research directions.

Committee:

Qian Chen, Dr. (Advisor)

Subjects:

Civil Engineering; Comparative Literature; Computer Science

Keywords:

Construction Industry; Big Data; Data Analytics; Data mining; Artificial Neural Network; ANN; Compressive Strength; Environmentally Friendly Concrete; Soil Erosion; Highway Slope; Predictive Modeling; Comparative Analysis

Dang, Thuy DinhMolecular/Nano Level Approaches for the Enhancement of Axial Compressive Properties of Rigid-Rod Polymers
PhD, University of Cincinnati, 2009, Arts and Sciences : Chemistry
The rigid-rod polymeric fibers, such as Zylon (PBO, Poly(p-phenylenebenzobisoxazole), are exceptional with regard to their tensile properties, yet their poor to modest axial compressive properties have been their Achilles' heel, limiting their ultimate potential, especially for structural applications requiring tolerance to compressive loadings. The poor axial compressive strength of the polymer fibers is widely attributed to insufficient lateral interactions between the highly oriented rigid-rod molecules, causing the micro-fibrils to buckle under an axial compressive load.The main objective of this thesis is to provide an insightful review, based on investigation of some molecular/nano-level approaches, for the improvement of the axial compressive properties of these highly oriented polymeric fibers. The predominant molecular approaches discussed are based on the lateral stabilization of the rigid-rod polymer chains via thermal cross-linking or introduction of lateral association, such as inter-chain hydrogen bonding, to provide supramolecular structures. While examples of lateral hydrogen bonding in rigid-rod polymers invariably involve the benzobisimidazole structure in the polymer backbone, other rigid-rod molecular motifs such as benzobisthiazoles linked to a terphenyl system with aromatic heterocyclic pendants are also discussed from the viewpoint of enhancing polymer fiber compressive strength. It is presumed that the twisted terphenyl system with bulky substituents can disrupt molecular rigidity while facilitating strong lateral interactions between the aromatic heterocyclic pendants, leading to enhanced fiber compressive strength. In the context of the nano level approach to the problem of axial compressive strength, in situ polymerization of PBO in the presence of SWNTs (single-wall carbon nanotubes), the fabrication and characterization of PBO/SWNT hybrid polymer fibers as well as the evaluation of their mechanical properties are also discussed. Relative to control PBO fibers, PBO/SWNT composite fibers were found to exhibit higher axial compressive strength.

Committee:

James Mark, PhD (Committee Chair); Neil Ayres, PhD (Committee Member); Estel Sprague, PhD (Committee Member); James Mark, PhD (Advisor)

Subjects:

Chemistry

Keywords:

axial compressive strength; rigid-rod polymer; mechanical properties; Poly(p-phenylenebenzobisoxazole); fibers; carbon nanotube

McDonnell, Thomas FrancisEFFECT OF MINERAL ADMIXTURES AND COARSE AGGREGATE SIZE ON COMPRESSIVE STRENGTH AND FREEZE-THAW RESISTANCE OF PORTLAND CEMENT CONCRETE
Master of Science, University of Akron, 2007, Civil Engineering
The Ohio Department of Transportation (ODOT) has developed a series of portland cement concrete mix designs for use on all infrastructure projects throughout the state. The standard forms of these mix designs differ in terms of the compressive strength they are expected to achieve after a curing period of 28 days. Because of the state’s climate, one requirement common to every mix design used by ODOT, however, is high resistance to damage from cycles of freezing and thawing. Options currently permitted by ODOT for varying these mix designs include the use of different coarse aggregate sizes and substitution of a portion of the portland cement with additional fine aggregate or one of three mineral admixtures. These admixtures include fly ash, ground granulated blast furnace slag (GGBFS) and micro silica. All of these admixtures are produced from materials that are recycled from processes unrelated to concrete production. These processes include coal fired steam generation, pig iron production and silicon manufacturing. The objective of the research presented in this thesis was to evaluate the effect that mineral admixtures and coarse aggregate on ODOT Class C (4,000 psi) concrete in terms of compressive strength and freeze-thaw resistance. These evaluations were performed through laboratory testing of specimens cast from individual mixes. Information is provided on the materials used to create a concrete mix, as well as a brief summary of the development of mix design methodologies. Detailed descriptions of the freeze-thaw resistance and compressive strength testing are also included, with a discussion of the associated mechanisms of failure. Conclusions are offered based on trends observed from analysis of the test data. In general, the results of the testing indicate that freeze-thaw resistance is not detrimentally influenced by the addition of mineral admixtures or the size of the coarse aggregate used. Each of the mineral admixtures does affect the resulting concrete mix in slightly different ways, and one may be more desirable than another based on required performance. In addition, all of the mix designs studied attained average compressive strengths in excess of the target value of 4,000 psi.

Committee:

Craig Menzemer (Advisor)

Subjects:

Engineering, Civil

Keywords:

mix designs; COARSE AGGREGATE; COMPRESSIVE STRENGTH; CONCRETE; mix; FREEZE-THAW; ODOT

Griffin, Jason AllanDEVELOPMENT OF A RATING CLASSIFICATION FOR ROCK TO BE USED AS TOE-BENCH MATERIAL
MS, Kent State University, 2008, College of Arts and Sciences / Department of Geology
Engineering properties of a rock considered suitable for rock toe benches in highway embankments are different than the properties required for fill material. A method of evaluating toe-bench material is needed to assess various rock strata that are encountered during preliminary site investigations for highways so that easy distinctions can be made between rock preferred for toe benches, rock favored for use as fill material, and rock that is not suitable for either. Rock quality is assessed on the basis of absorption, density, slake durability, unconfined compressive strength, freeze-thaw durability, and L.A. abrasion loss. These are considered important properties in defining the integrity of the rock, and provide for a basis for systematic evaluation of rock material. A rating classification for evaluating rock material from Carboniferous strata of western Pennsylvania for use as toe-bench material is presented herein. A series of laboratory tests were performed on three sandstone and two limestone rock units for differentiation on the basis of strength, durability, and overall usefulness as a fill material. Samples were collected from five Mississippian-Pennsylvanian strata consisting of low to high durability rock. Typically, low durability rock units such as shales, claystones, and siltstones, etc., are neglected considering their infrequent use as durable rock fill. Specifications for acceptance of rock toe material do not currently exist within state and federal construction manuals. Therefore, research was conducted to determine the commonly specified engineering property values for rock fill applications in highway construction. These engineering properties were then used to determine rational cutoff boundary values for acceptance of rock material for use within a rock toe structure. Values for various properties tested range from 0.26-4.7% for absorption, 2.46-2.67 for specific gravity, 154-170 pounds per cubic foot (pcf) (2.47-2.72 Mg/m3) for bulk density , 0.7-11.6% for porosity, 10,300 to over 25,000 pounds per square inch (psi) (71-172 Mpa) for unconfined compressive strength, 97.3-99.6% for slake durability index, 21.2-45.9% for L.A. abrasion loss, and 1.5-21% for freeze-thaw loss. Bivariate statistical analysis showed a lack of significant correlations within the data set. Compressive strength showed the best correlation with bulk specific gravity (r2 = 0.61) and exhibited modest relationships with L.A. abrasion loss (r2 = 0.52) and with the value of L.A. abrasion divided by bulk specific gravity (r2 = 0.58). Based on the test data produced, an evaluation of rock material is conducted on the five rock units studied. Each rock unit is categorized as passing, marginal, or failing based on the previously determined cutoff boundaries. Predicted values of engineering properties from bivariate correlation equations produced similar results in the evaluation, although based only on compressive strength as estimated by other index properties. The use of empirical equations is considered to be marginally useful as only values of unconfined compressive strength, L.A. abrasion, and bulk specific gravity could reasonably be determined in this manner. Test data proved to be useful in determining the relative, and to a lesser extent, overall quality and durability of rock material for use in rock toe structures, as defined by other uses of rock fill material in highway and embankment construction.

Committee:

Abdul Shakoor, PhD (Advisor); Peter Dahl, PhD (Committee Member); Ernest Carlson, PhD (Committee Member)

Subjects:

Civil Engineering; Engineering; Geology

Keywords:

geology; rock; toe; bench toe-bench; strength; durability; classification; rating; material; geotechnical; slope; stability; embankment; carboniferous; western; pennsylvania; key; berm; compressive strength; abrasion: L.A.; LA; engineering;

McFaddin, Jared DouglasDevelopment of Correlations for Unconfined Compression Strength and Methods of Field Preparations and Preservation of Kope Shale
MS, University of Cincinnati, 2008, Engineering : Civil Engineering
In the Greater Cincinnati area, the Kope formation and in particular Kope shale is problematic for engineers and geologists because of its ever-changing strength and durability properties. The purpose of this research was to collect Kope shale samples and preserve them by two different methods: one set was plastic wrapped and the other was waxed per ASTM standards. Unconfined compression, slake durability, jar slake, Atterberg limits, clay percent, free swell, and swell pressure tests were then conducted on these sample at selected time intervals (1, 5, 7, 30, 365 days). As the natural moisture content of the Kope shale samples decreased, an increase in these samples’unconfined compressive strength (UCS) was observed. Similarly, as the natural moisture content decreased the samples’ durability increased. The plastic wrapped samples lost moisture at a more rapid pace than did the waxed samples. As the samples aged and lost moisture with time their UCS and durability increased. Moisture content plays a key role in the strength and durability of this weak shale. How these samples are preserved and how long before they are tested critically affects the test results.

Committee:

Mark Bowers, PhD (Committee Chair); T. Michael Baseheart, PhD (Committee Member); Warren Huff, PhD (Committee Member); J. Barry Maynard, PhD (Committee Member)

Subjects:

Civil Engineering

Keywords:

Kope; shale; compressive; strength; durability; Cincinnati; swell; UCS; weak rock; moisture content

Rudd, Jeffrey RoyCOMPRESSIVE STRENGTH TO WEIGHT RATIO OPTIMIZATION OF COMPOSITE HONEYCOMB THROUGH ADDITION OF INTERNAL REINFORCEMENTS
Master of Science, University of Akron, 2006, Mechanical Engineering
This work focuses on the compressive strength to weight ratio optimization of reinforced composite honeycomb materials for sandwich panel construction. Currently, metallic honeycomb has densities up to four times that of composite honeycomb, and compressive strengths up to ten times greater. The objective of this research is to eliminate the use of aluminum honeycomb in aircraft structures by replacing them with reinforced composite honeycomb with equivalent or better compressive strength. In order to evaluate reinforced composite alternatives, a finite element model was developed to analyze many reinforcement configurations. The analysis was extremely non-linear and required significant work to develop a model that would successfully converge to a solution for the many different reinforced configurations to be analyzed. A parametric study showed that the crushing resistance of the reinforcement governed the overall compressive strength to weight ratio of the reinforced composite honeycomb. It was found that the compressive strength to weight ratio of reinforced composite honeycomb can be 22% higher than that of aluminum honeycomb of comparable weight.

Committee:

Michelle Hoo Fatt (Advisor)

Keywords:

honeycomb; compressive strength; aircraft; sandwich panel; composite