Open Access. Powered by Scholars. Published by Universities.®
- Discipline
-
- Physical Sciences and Mathematics (8)
- Chemical Engineering (5)
- Earth Sciences (4)
- Environmental Engineering (4)
- Environmental Sciences (4)
-
- Materials Science and Engineering (4)
- Petroleum Engineering (4)
- Transportation Engineering (4)
- Architecture (2)
- Geophysics and Seismology (2)
- Geotechnical Engineering (2)
- Sustainability (2)
- Urban, Community and Regional Planning (2)
- Biogeochemistry (1)
- Chemistry (1)
- Computational Chemistry (1)
- Construction Engineering (1)
- Construction Engineering and Management (1)
- Engineering Mechanics (1)
- Engineering Science and Materials (1)
- Environmental Chemistry (1)
- Geological Engineering (1)
- Geology (1)
- Polymer Science (1)
- Structural Engineering (1)
- Structural Materials (1)
- Water Resource Management (1)
- Keyword
-
- Columns (13)
- Strains and stresses. (10)
- Concrete (7)
- Concrete--Testing. (7)
- Fly ash (7)
-
- Concrete. (6)
- Reinforced concrete (6)
- Concrete columns -- Testing (5)
- Fiber reinforced concrete (5)
- Fracture mechanics (5)
- Rock mechanics (5)
- Strains and stresses (5)
- Clay soils (4)
- Concrete -- Testing (4)
- Fracture mechanics. (4)
- Reinforced concrete construction (4)
- Reinforced concrete. (4)
- Bentonite -- Permeability (3)
- Biodegradation (3)
- Fluorimetry. (3)
- Fracture mechanics--Environmental aspects. (3)
- Humic acid. (3)
- Hydraulic fracturing (3)
- In situ remediation. (3)
- Piling (Civil engineering) (3)
- Pneumatics--Environmental aspects. (3)
- Reinforced concrete construction--Testing. (3)
- Sewage--Purification--Activated sludge process. (3)
- Shear (Mechanics) (3)
- Water chemistry. (3)
- Publication Year
- Publication
Articles 61 - 90 of 258
Full-Text Articles in Civil Engineering
Impact Of Truck Regulation And 65mph Speed Limit On Truck Accidents In New Jersey, Rajat G. Rajbhandari
Impact Of Truck Regulation And 65mph Speed Limit On Truck Accidents In New Jersey, Rajat G. Rajbhandari
Theses
The state of New Jersey enacted two regulations with significant importance to the highway operations: 65 mph speed limit and truck restriction on the National Network. The speed limit of 65mph was used on limited sections of interstate system highways with an objective to reduce energy consumption by vehicles and truck restriction was used on the interstate system and other state highway system to reduce large truck accidents and thereby increase truck safety. In this research, the safety impacts of these two regulations on truck crashes were studied.
The research focused on monthly truck crashes along the highway sections where …
Seismic Response Of Transformer Bushing Systems And Their Rehabilitation Using Frictional Pendulum System, Selahattin Ersoy
Seismic Response Of Transformer Bushing Systems And Their Rehabilitation Using Frictional Pendulum System, Selahattin Ersoy
Dissertations
This thesis is concerned with the performance of electric power transformers and their attachments under earthquake loading. It begins with the description of the transformers, attached bushings, and some typical examples of substation failures in earthquake loading. This is followed by the development of finite element model of three different sizes of transformers. Finite element models consist of several thousand degrees of freedom and they are basic to this thesis. Some of the major findings from these models are utilized to derive a simplified model of a portion of a substation, The frictional pendulum system (a base isolation method) is …
Inelastic Seismic Behavior Of Stiffening Systems : Multi-Span Simply-Supported (Msss) Bridges, Alireza Yazdani-Motlagh
Inelastic Seismic Behavior Of Stiffening Systems : Multi-Span Simply-Supported (Msss) Bridges, Alireza Yazdani-Motlagh
Dissertations
Stiffening behavior can result from interaction between a structure (base system) and its surrounding environment as in the MSSS bridge soil-structure interaction. In this study, three MSSS bridge cases are parametrically analyzed and their dynamic characteristics and behavior are presented and discussed. Later, for investigating stiffening behavior, a simplified stiffening model is introduced and an extensive parametric study with more than 367,000 analyzed cases is performed. In the parametric study, different stiffening parameters (i.e., stiffness, strength, gap size, and mass), 41 strong motion records, and several damage criteria are considered and effects of the stiffening parameters variations on the dynamic …
Shear Behavior Of Reinforced Concrete Deep Beams Strengthened With Cfrp Laminates, Jon Erik Moren
Shear Behavior Of Reinforced Concrete Deep Beams Strengthened With Cfrp Laminates, Jon Erik Moren
Theses
Considerable research has been performed using CFRP plates bonded to normal reinforced concrete beams, the objective being to improve shear and flexural strength. However, very few tests have been performed on reinforced concrete deep beams with CFRP as shear reinforcement. The purpose of this experiment is to investigate the behavior of the deep beam in shear with various arrangements of Sika CarboDur laminates bonded to the sides. The beams were designed to be shear deficient with stirrups omitted, except at the supports and directly under the load. In total eight beams were tested, four with one-point loading and four with …
Mechanical Properties And Stress-Strain Behavior Of High Performance Concrete Under Uniaxial Compression, Pornchai Jiratatprasot
Mechanical Properties And Stress-Strain Behavior Of High Performance Concrete Under Uniaxial Compression, Pornchai Jiratatprasot
Theses
Many recent innovations in advanced concrete materials technology have made it possible to produce concrete with exceptional performance characteristics. High performance concrete (HPQ is defined as concrete that meets special performance and uniformity requirements that cannot always be achieved routinely by using conventional materials and normal mixing, placing, and curing practices. The importance of HPC to structural engineering is unquestionable. However, HPC is a relatively new material. Some results of research on conventional concrete are not entirely applicable. In this experiment, the main mechanical properties of HPC including compressive strength, modulus of elasticity, and Poisson's ratio were investigated and compared …
Fractionation & Segregation Of Suspended Particles Using Acoustic And Flow Fields, Nazhat Aboobaker
Fractionation & Segregation Of Suspended Particles Using Acoustic And Flow Fields, Nazhat Aboobaker
Dissertations
The fractionation of particles by size or by density has many applications in a variety of technologies. Decontamination and separation of fine sediments is useful in treating sediments. The application of acoustic standing wave fields for the fractionation and segregation of suspended particles was studied.
The above technology was implemented at the bench scale by building a Plexiglas chamber. Two ultrasound transducers were fixed to opposite sides of the chamber to generate the acoustic standing wave field. The technology was evaluated using silica dioxide (Si02) (1-5 ~tm) and silicon carbide (SiQ (5-20 ~tm) particle suspensions in deionized water. Due to …
A Software System For Large-Scale Structural Optimization, Keith M. Macbain
A Software System For Large-Scale Structural Optimization, Keith M. Macbain
Dissertations
This work is driven by recent developments in mathematical programming, the state-of-the-art of structural optimization, the spectacular performance of linear programming algorithms, and computer hardware developments which imply that applications of structural optimization might be used commonly in engineering design. Currently, there are few general purpose optimization routines available to the structural engineer and much of the work has addressed specific classes of problems. Further, there is little widespread use of the available routines, partly due to the large amount of familiarity one must have with the specific details of both the problem and the optimization method. In response, it …
Characterization Of The Dependant Pile Capacity In Glacial Deposits By Dynamic Load Tests, Upendra L. Karna
Characterization Of The Dependant Pile Capacity In Glacial Deposits By Dynamic Load Tests, Upendra L. Karna
Theses
A study of the effects of time on axial pile capacity in glacial deposits is presented in this report. The dynamic and static load database test results of the Route 21, Viaduct Replacement project are studied and analyzed. In this project two sizes (18-inch and 24-inch dia.) of closed end pipe piles varying in length 100 to 150 feet driven through highly variable glacial deposits were utilized. Within a small reach the subsurface conditions and the behavior of pile capacity with time varied considerably. About 112 piles were tested dynamically by Pile Driving Analyzer. Restriking was performed on fifty-nine piles …
Reactive Media For Chromium Reduction Under Alkaline Conditions For Use In Permeable Reactive Barriers, Sachin V. Apte
Reactive Media For Chromium Reduction Under Alkaline Conditions For Use In Permeable Reactive Barriers, Sachin V. Apte
Theses
The purpose of this study was to select the appropriate reactive media for chromate reduction to treat groundwater (high pH) with permeable reactive barriers. The study addresses groundwater contamination for three chromium refining sites located in Hudson County, New Jersey. The use of iron (Fe0) as a reactive medium was studied and found to be insufficient for use in permeable reactive barriers because of the high pH conditions of groundwater at these sites. Pyrite and iron (Fe0)-pyrite mixtures were studied as viable reactive media by considering their passivation kinetics, reductive capacities and solubility properties.
Column experiments …
Feasibility Study To Extract Iron And Chromium From Chromium Contaminated Soils, Wiwat Kamolpornwijit
Feasibility Study To Extract Iron And Chromium From Chromium Contaminated Soils, Wiwat Kamolpornwijit
Dissertations
Chromium contaminated soils, besides being recognized for toxic and hazardous hexavalent chromium, contain high iron concentrations. At some sites, concentrations of iron oxide are higher than 30%. Both iron and chromium in soils have recyclable value provided they can be either concentrated in the oxide form or separated as metal. The concentrated oxide can be used as a substitute for the iron ore. The extracted metal can also be recycled in the steel industry. The objective of this study is to study the feasibility of extracting iron and chromium from soils.
Chromium contaminated soils, can be classified into two groups, …
Multimedia Modeling Of Organic Contaminants In The Passaic River Watershed, Lansana Coulibaly
Multimedia Modeling Of Organic Contaminants In The Passaic River Watershed, Lansana Coulibaly
Dissertations
A dynamic fate and transport multimedia environmental model was developed and applied to assess the release of five priority contaminants in the Passaic River Watershed, including: napthalene, toluene, trichloroethylene, 1-1-1 trichloroethane and xylene. The model uses the current releases of contaminants as well as cross-boundary advection to determine the fate and environmental distribution of these chemicals in the watershed. The model was developed using a dynamic fugacity approach in order to allow for scenario analysis such as source reductions and no-action alternatives. This modeling effort is expected to achieve a comprehensive assessment of contaminants not only in the proximity of …
Performance-Based Seismic Engineering Of Low And Medium-Rise Steel Frames, Saeid Rashidi
Performance-Based Seismic Engineering Of Low And Medium-Rise Steel Frames, Saeid Rashidi
Dissertations
The performance level of low and medium-rise steel frames designed according to the common force/strength approach of the UBC or NEHRP is determined. Several combinations of soil profile type, lateral-force-resisting system, and frame-member proportioning are included in the designs.
To evaluate the expected damage, nonlinear models of the designed frames are subjected to a number of actual and simulated ground motion accelerograms and appropriate structural response parameters such as, interstory drift, ductility demand, and dissipated hysteretic energy are obtained. In addition, a modified form of Park-Ang damage index is calculated for moment-resisting frames. The seismic performance of the steel frames …
The Influence Of High Performance Matrices On Fracture Behavior Of Concrete, Pusit Lertwattanaruk
The Influence Of High Performance Matrices On Fracture Behavior Of Concrete, Pusit Lertwattanaruk
Dissertations
Modification of cement matrices by the addition of micro particle pozzolanic materials such as silica fume and fly ash is known to improve the strength of concrete, but its contributions to fracture behavior remains unclear. In this study, the influence of replacing cement by silica fume and fly ash on the cement matrix-coarse aggregate interfacial bond, compressive stress-strain behavior and fracture behavior of concrete is investigated.
While the linear elastic fracture mechanics (LEFM) concept is not appropriate for concrete, a nonlinear fracture model based on the load vs. load-line deflection and the load vs. crack-mouthopening displacement (CMOD) responses of the …
Utilization Of Municipal Solid Waste Incinerator Fly Ash In Cement Mortars, Manaskorn Rachakornkij
Utilization Of Municipal Solid Waste Incinerator Fly Ash In Cement Mortars, Manaskorn Rachakornkij
Dissertations
Disposal of municipal solid waste has become a major problem in many countries around the world. With the benefits of substantial weight and volume reduction and potential energy recovery, incineration has become a promising municipal solid waste (MSW) management option. Despite the fact that incineration reduces volume and mass of the wastes by as much as 80%, there are still residues to be properly managed. This research is aimed at evaluating the potential of different types of MSWI fly ash from an incineration facility to be used in cement mortars by using existing standard test methods for cement and coal …
Finite Fraction Method For Tracking Desinfection By-Product Precursors In Water Treatment, Doanh Van
Finite Fraction Method For Tracking Desinfection By-Product Precursors In Water Treatment, Doanh Van
Dissertations
Dissolved Organic Matter (DOM) has been the subject of recent regulatory activities and agenda. Among them are the Infonnation Collection Rule (ICR), the Disinfectants/Disinfection By-Product Rule (D/DBPR) and the Interim Enhanced Surface Water Treatment Rule (ESWTR). Both the latter two have provisions to limit the formation of disinfection by-products (DBP) by controlling reactivity and removal of DOM or both. Brief regulatory review of these rules was given.
Although the topic of DBP formation potential and DBP precursor removal have been studied by many researchers since Rooks (1974), the efficacy of methods that have been developed to date has been handicapped …
Post-Cracking Tensile Properties Of Advanced Cementitious Materials And Ductility Of High Performance Concrete Beams, Wonsiri Punurai
Post-Cracking Tensile Properties Of Advanced Cementitious Materials And Ductility Of High Performance Concrete Beams, Wonsiri Punurai
Theses
In present direct tension tests, the complete stress-deformation curves, the resulting energy dissipated by damage, and the fracture energy of different types of cementitious composites, namely plain concrete, high strength concrete, normal fibrous concrete, high strength fibrous concrete, are studied and a ductility factor is calculated. It has been found that with the increasing strength of concrete due to the addition of the pozzoians such as silica fume and fly ash and when changing from normal strength to high strength, concrete ductility decreases. However, when fibers are combined with these matrices, concrete ductility increases. It is because of ductile steel …
Long Term Risks Associated With Brownfield Containments, Shailesh Shirish Chirputkar
Long Term Risks Associated With Brownfield Containments, Shailesh Shirish Chirputkar
Dissertations
The sites at which the development is hindered by real or perceived contamination are called as Brownfield sites. It is a common trend in industry to develop these types of sites with surface and peripheral containments. It might prove unwise to develop the sites in this manner from a long term perspective without considering the associated risk. Because of this, a model has been proposed for long term risk assessments of brownfield containments.
Objectives of this study were to develop a contaminant transport model for flow of contaminants towards the surface and peripheral containments inside the site, a model for …
Physical And Geotechnical Characterization Of Water Treatment Plant Residuals, Swamy C. Basim
Physical And Geotechnical Characterization Of Water Treatment Plant Residuals, Swamy C. Basim
Dissertations
The study of Water Treatment Plant (WTP) residuals is of recent origin and very little information is available in literature regarding these residuals. These waste materials have high solids contents, even in the mechanically dewatered condition, making it difficult to handle. These, along with stringent environmental regulations have forced the water utilities to look for new disposal options for these residuals. For this purpose as well as for evaluating suitable options for the beneficial reuse of residuals, it is essential to characterize WTP residuals.
As the dewatered residuals are plastic, the researcher may be prompted to treat these materials as …
Development Of Computer Model And Expert System For Pneumatic Fracturing Of Geologic Formations, Brian Michael Sielski
Development Of Computer Model And Expert System For Pneumatic Fracturing Of Geologic Formations, Brian Michael Sielski
Dissertations
The objective of this study was the development of a new computer program called PF-Model to analyze pneumatic fracturing of geologic formations. Pneumatic fracturing is an in situ remediation process that involves injecting high pressure gas into soil or rock matrices to enhance permeability, as well as to introduce liquid and solid amendments. PF-Model has two principal components: (1) Site Screening, which heuristically evaluates sites with regard to process applicability; and (2) System Design, which uses the numerical solution of a coupled algorithm to generate preliminary design parameters.
Designed as an expert system, the Site Screening component is a high …
Design And Engineering Of A Tensile Fabric Structure, Jairo Rios
Design And Engineering Of A Tensile Fabric Structure, Jairo Rios
Theses
Fabric structures are designed in an iterative process between architect and engineer, analysis input and output, and detail and patterning. There are three main steps in designing a fabric structure: shape finding, loading, and patterning/ detailing.
Shapefinding consists of finding the shape of the fabric where the fabric forces are in equilibrium. This type of structure is geometrically nonlinear which require iterative analysis to converge on a unique solution.
The loading of the structure is similar to that of any conventional structures. The departure is in the major effects that suction and ponding have on fabric surfaces.
Usually the details …
In Situ Enhancement Of Well Recovery By Pneumatic Media Injection, Michael Thomas Galbraith
In Situ Enhancement Of Well Recovery By Pneumatic Media Injection, Michael Thomas Galbraith
Theses
The objective of this thesis was to develop a new process for enhancing recovery wells at hazardous waste sites. The process, known as an extended radius well (ERW), involves injection of ceramic beads directly into groundwater plumes to create drainage paths for liquid contaminants. This is a variant of Pneumatic Fracturing, which is a patented in situ remediation process developed to increase permeability of soil and rock formations by injection of high pressure gas.
The research study comprised laboratory investigations, engineering scale tests, and a field pilot demonstration. The laboratory investigations examined the properties of several candidate media to determine …
Fluorescence Spectroscopy For The Characterization Of Humic And Fulvic Acids And Their Disinfection By-Products Formation Potential, Ishvinder H. Kochar
Fluorescence Spectroscopy For The Characterization Of Humic And Fulvic Acids And Their Disinfection By-Products Formation Potential, Ishvinder H. Kochar
Theses
Natural Organic Matter (NOM) plays a major role in the formation of undesirable organic by-products following disinfection/oxidation of drinking water. It is suspected that most precursors to disinfection by-products (DBPs) are humic although non-humic substances have not been studied and are suspected of also contributing to DBPs. NOM reacts with many of the disinfectants used to treat drinking water, such as chlorine, chioramine, and ozone, to form a variety of DBPs. Many of these DBPs have adverse health effects in humans (i.e. carcinogenic or mutagenic effects). The primary DBPs of concern include the trihalomethanes (THMs), haloacetic acids (HAAs), and haloacetonitrile …
Pneumatic Fracture Propagation And Particulate Transport In Geologic Formations, Suresh Puppala
Pneumatic Fracture Propagation And Particulate Transport In Geologic Formations, Suresh Puppala
Dissertations
Pneumatic fracturing is an in situ remediation enhancement technology developed to increase the permeability of contaminated geologic formations. This technology can also be used to deliver atomized liquid and particulate supplements to geologic formations, thereby enhancing in situ processes such as bioremediation and reactive dechlorination.
The main objective of this study was the development of a mathematical model that simulates the propagation of pneumatic fractures in soil and rock formations. Pneumatic fracture propagation differs from other fluid fracturing phenomena in the propagation velocity (1-3 m/sec) and the viscosity of the fracturing fluid (1.9E-05 Pa•sec). For the purposes of model development, …
Composite Columns, Magnar Berge
Composite Columns, Magnar Berge
Theses
The purpose of this thesis is to provide an introduction in the design of composite columns. The design methods according to AISC and Eurocode 4 are summarized and provide a procedure to design a composite column. In addition, equation are derived to determine the nominal flexural strength of typical composite cross-sections.
Reuse Of Cold Top Ex-Situ Vitrified Chromium Contaminated Soils In Hot Mix Asphalt Concrete, Gerald Charleston
Reuse Of Cold Top Ex-Situ Vitrified Chromium Contaminated Soils In Hot Mix Asphalt Concrete, Gerald Charleston
Theses
This research investigated the pilot scale feasibility of the remediation of chromium contaminated soil through cold top ex-situ vitrification and the reuse of the vitrified products as highway construction aggregates. There are more than two million tons of chromite ore residues from the chromate extraction manufacturing leftover in Hudson County, New Jersey. They contained both un-leached hexavalent and unoxidized trivalent chromium. Hexavalent chromium is well known as a group A human carcinogen. It is also considered an environmental and health hazard. Of the many ex- situ and in-situ physical, chemical, and biological treatment technologies for chromate production waste, the ability …
Fluorescence Spectroscopy For The Characterization Of Total Organic Carbon And Disinfection By-Product Formation, Matthew Brendan Washington
Fluorescence Spectroscopy For The Characterization Of Total Organic Carbon And Disinfection By-Product Formation, Matthew Brendan Washington
Theses
One of the concerns facing the drinking water industry is the formation of disinfection by-products (DBPs) during the disinfection stage of treatment. Organic DBPs form during the oxidation of the natural organic matter (NOM) found in natural waters by the application of a disinfectant, such as chlorine.
NOM is composed of two aggregate materials, humic and non-humic substances. It is unknown which portions of NOM react with the oxidant to form DBPs. Methods used to predict the formation of DBPs include total organic carbon (TOC) analysis and Trihalomethane Formation Potential (THMFP), which are time consuming and do not give specific …
Analysis Of Safe Separation Distances From Natural Gas Transmission Pipelines, James Stephen Haklar
Analysis Of Safe Separation Distances From Natural Gas Transmission Pipelines, James Stephen Haklar
Dissertations
Accidental rupture of natural gas transmission pipelines with subsequent ignition of the escaping gas can result in the loss of life and property. In the United States, current means of protecting both the pipeline and the public include the establishment of class locations, in which specific pipeline design, construction and operation requirements must be attained. In addition, distances at which the pipelines can be safely set back from the community, called safe separation distances, have been developed in some European countries (e.g., Great Britain, the Netherlands) through use of risk assessment principles. However, to date there has been no simple, …
Characteristics Of Recycled Plastics And Applications For Highway Appurtenances, Keith Macbain
Characteristics Of Recycled Plastics And Applications For Highway Appurtenances, Keith Macbain
Theses
Recycling is gaining widespread support in many communities as an environmentally acceptable solution to the management of solid waste. The success of these recycling programs depends largely on the development of high-value end use for the recycled products. This research involves an experimental and analytical study on the development of high-value, high-volume end uses for recycled plastic shapes. The experimental part includes material tests to determine mechanical properties of various recycled plastics. A constitutive model is proposed and verified that can be used in characterization of recycled plastics. Bending tests of recycled plastic beams were performed to assess strength, stiffness …
Distribution Of Velocities And Velocity Gradients In Mixing And Flocculation Vessels : Comparison Between Ldv Data And Cfd Predictions, Changgen Luo
Dissertations
Flocculation is an operation of significant industrial relevance commonly encountered in many processes, including water and wastewater treatment. The physico-chemical phenomena of this process is strongly affected by the magnitude of the velocity gradients generated, typically through agitation, in rapid mix devices and flocculation vessels.
In this work the fluid dynamic characteristics of mechanically agitated systems, namely three different types of stirred tanks, which can be used as flocculation vessels, were studied. Both the mean and fluctuating velocities in all three directions were measured by using a Laser-Doppler Velocimeter (LDV). The velocity distribution, fluctuating velocities, power consumption and local velocity …
Analysis And Modeling Of Ultrasound Enhanced Soil Washing Process, Kamalavathany Rajaratnam
Analysis And Modeling Of Ultrasound Enhanced Soil Washing Process, Kamalavathany Rajaratnam
Theses
In this research, statistical analysis of data from ultrasound enhanced soil washing process was performed. The process was optimized using a statistical model. The model had four factors namely power, solvent:soil, surfactant, and dwell time as process variables. The percentage of removal efficiency was considered as the dependent variable. The results from two full and one partial factorial designs were analysed. Interactions up to third order were considered in the analysis, but the results from full factorial design showed that those of order higher than second had insignificant contributions to the removal of contaminants. Since the higher order interactions of …