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Full-Text Articles in Engineering

Strain Rate And Aging Effect On The Mechanical Properties Of Sheet Steels, Chi Ling Pan, Shaojie Wu, Wei Wen Yu May 2001

Strain Rate And Aging Effect On The Mechanical Properties Of Sheet Steels, Chi Ling Pan, Shaojie Wu, Wei Wen Yu

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study was primarily involved with the experimental determination of the dynamic mechanical properties of five different sheet steels. The nominal yield strengths of these five types of sheet steels ranged from 172 to 690 MPa (25-100 ksi) and the range of strain rates varied from 10-4 to 1.0 mm/mm/s. All these five materials were studied in both longitudinal and transverse directions under various strain rates, and some materials were also tested under different strain rates and different amounts of prior cold stretching. In addition, two types of steels were tested to estimate the aging effect on the mechanical properties …


Asymmetric Low-Velocity Impact Of A Finite Layer, Minggang Zhou, William P. Schonberg May 2001

Asymmetric Low-Velocity Impact Of A Finite Layer, Minggang Zhou, William P. Schonberg

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The dynamic indentation of structural elements such as beams and plates continues to be an intriguing problem, especially for scenarios where large area contacts can occur. Standard methods of indentation analysis typically use a dynamic beam theory solution to obtain an overall load-displacement relationship and then a Hertzian contact solution to determine local stresses under the impactor. However, previous static and dynamic modeling efforts have shown that the stress distribution in the contact region will differ significantly from a Hertzian one when the contact length exceeds the thickness of the beam. In such cases point contact can no longer be …


Diagnostic Load Testing Of Two-Way Posttensioned Concrete Slab, Antonio Nanni, M. Mettemeyer May 2001

Diagnostic Load Testing Of Two-Way Posttensioned Concrete Slab, Antonio Nanni, M. Mettemeyer

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Diagnostic load testing techniques have been used to verify in situ that existing structures have the required load-carrying capacity. This paper discusses the diagnostic load testing and finite-element modeling of a two-way posttensioned concrete slab with the purpose of illustrating the features of this full-scale testing method. The slab was modeled using a commercial finite-element package and the results were verified experimentally. The test loads were applied using hydraulic jacks. Negative internal bending moments were generated at critical locations equivalent to those produced by a 92 psf (4.40 kPa) superimposed uniformly distributed load. Positive internal bending moments were also produced …


Self-Monitoring, Pseudo-Ductile, Hybrid Frp Reinforcement Rods For Concrete Applications, C. E. Bakis, Antonio Nanni, J. A. Terosky, S. W. Koehler May 2001

Self-Monitoring, Pseudo-Ductile, Hybrid Frp Reinforcement Rods For Concrete Applications, C. E. Bakis, Antonio Nanni, J. A. Terosky, S. W. Koehler

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The feasibility of hybrid -fiber-reinforced-polymer rods that demonstrate the important safety features of self-monitoring capability and pseudo-ductility is demonstrated. The rods are intended to be the basis of improved pultruded reinforcements for concrete or other civil applications where safety is of critical importance. The lowest elongation fiber in the seven rods investigated is carbon, which by virtue of its piezo resistivity allows the monitoring of deformation and fracture throughout an entire rod with simple electronic equipment. Resistance measurements obtained during quasi-static tests clearly reveal failure of the carbon fibers. Following this easily detected event, higher loads can be safely sustained …


Characterization Of Frp Rods As Near-Surface Mounted Reinforcement, Laura De Lorenzis, Antonio Nanni May 2001

Characterization Of Frp Rods As Near-Surface Mounted Reinforcement, Laura De Lorenzis, Antonio Nanni

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The use of near surface mounted (NSM) fiber-reinforced polymer (FRP) rods is a promising technology for increasing flexural and shear strength of deficient reinforced concrete (RC) members. As this technology emerges, the structural behavior of RC elements strengthened with NSM FRP rods needs to be fully characterized. Given the variability of material properties and groove geometry, this requires that the tensile properties of the FRP rod and the mechanics of load transfer between NSM FRP rods and concrete be investigated. Tensile and bond tests on commercially available carbon FRP deformed rods for application as NSM reinforcement were carried out using …


Destructive And Non-Destructive Testing Of Bridge J857 Phelps County, Missouri : Strengthening And Testing To Failure Of Bridge Piers, Tarek Alkhrdaji, Antonio Nanni, Genda Chen Apr 2001

Destructive And Non-Destructive Testing Of Bridge J857 Phelps County, Missouri : Strengthening And Testing To Failure Of Bridge Piers, Tarek Alkhrdaji, Antonio Nanni, Genda Chen

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Many of the existing reinforced concrete (RC) bridge piers constructed in the first half of this century were designed as gravity piers with minimal flexural reinforcement and no consideration to seismically induced lateral forces. When considered in earlier designs, the seismic lateral forces were typically low. The potential risk of failure of columns on these piers under a moderate earthquake is becoming a growing concern for the transportation management agencies. In addition, flexural strength deficiency in RC columns may arise from the loss of reinforcement due to corrosion, premature termination of the main reinforcement, or inadequate splicing. One method for …


Editor’S Note Advancement Of Phytoremediation, Joel Gerard Burken Mar 2001

Editor’S Note Advancement Of Phytoremediation, Joel Gerard Burken

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

No abstract provided.


Yield Moment Of Cold-Formed Steel Beams Under Different Strain Rates, Chi Ling Pan, Wei Wen Yu Mar 2001

Yield Moment Of Cold-Formed Steel Beams Under Different Strain Rates, Chi Ling Pan, Wei Wen Yu

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

It has been recognized that the mechanical properties of sheet steels and the structural strength of cold-formed steel members can be influenced by strain rate. For studying the local and post buckling behavior of stiffened and unstiffened compression elements under a dynamic loading condition, 60 beams, which were assembled from the same material, have been tested under different strain rates. To study the structural behavior of hybrid cold-formed steel beams, a total of 72 specimens was investigated. The results showed that the strength of beams increases with increasing strain rates. The amount of increase was found to be dependent on …


Guides And Specifications For The Use Of Composites In Concrete And Masonry Construction In North America, Antonio Nanni Jan 2001

Guides And Specifications For The Use Of Composites In Concrete And Masonry Construction In North America, Antonio Nanni

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper covers the latest developments in the preparation of design guidelines, construction specifications, and inspection and quality control recommendations related to the use of composites in construction. The forms of FRP composites addressed are limited to bars and laminates for reinforcement of concrete and masonry structures (new construction and repair/rehabilitation). FRP bars are being used as the internal reinforcement in concrete members when the conventional steel bars may be undesirable for a host of reasons (e.g., corrosion), and principles for design and construction have been established and proposed to industry by the American Concrete Institute (ACI). Conversely, strengthening of …


Composites In Construction: Present Situation And Priorities For Future Research, Antonio Nanni, Edoardo Cosenza, Gaetano Manfredi, Andrea Prota Jan 2001

Composites In Construction: Present Situation And Priorities For Future Research, Antonio Nanni, Edoardo Cosenza, Gaetano Manfredi, Andrea Prota

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper was written at the conclusion of the International Workshop titled "Composites for Construction: A Reality," held in Capri, Italy, July 20-21, 2001. Its objective is to collect and summarize main ideas, opinions, evaluations, and proposals that emerged during the discussions held by the participants at break-up and general sessions. For simplicity, the reporting follows the order of such sessions and includes elements from the general sessions when applicable. The paper is intended to help professionals and scientists interested in the study and implementation of composites for the built infrastructure by providing a vivid snapshot of the state-of-the-art situation, …


Permeability Performance Of High-Performance Concrete Subjected To Various Curing Regimes, John J. Myers Jan 2001

Permeability Performance Of High-Performance Concrete Subjected To Various Curing Regimes, John J. Myers

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Concrete technology has continued to advance throughout the years to meet the demands of designers and innovative structural systems. Traditionally, the most common means to specify durable concrete has been via specifying a maximum water-to-cementitious material ratio or a minimum cement content. With the advent of high-performance concrete (HPC), which often has higher contents of cementitious materials and a variety of admixtures, questions about permeability performance and alternative methods to specify durable concrete have arisen. The study conducted herein comments on the applicability of prescriptive specifications for HPC and investigates the influence of curing regimes and concrete temperature development during …


Experimental Procedure For Testing Of Piles Under Varying Axial And Lateral Loads, Pedro Franco Silva, F. Seible Jan 2001

Experimental Procedure For Testing Of Piles Under Varying Axial And Lateral Loads, Pedro Franco Silva, F. Seible

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

A research program was carried out at the University of California San Diego (UCSD) to study the seismic response of piles and their connections to the pier cap. As part of this research program, an experimental procedure for testing of piles under simulated seismic loading was developed. This experimental procedure was implemented in a research program to test the as-built piles of the San Diego Coronado Bay Bridge piles in order to validate the design criteria recommended by the design team for the seismic retrofit of the Coronado Bay Bridge.


Experimental Characterization Of Metallic Dampers For Seismic Retrofit Of Highway Bridges, Genda Chen, Eric R. Bothe, Jeffrey Ger Jan 2001

Experimental Characterization Of Metallic Dampers For Seismic Retrofit Of Highway Bridges, Genda Chen, Eric R. Bothe, Jeffrey Ger

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The seismic effectiveness of metallic dampers as vibration isolators and energy dissipation devices as well as the dynamic performance of high rocker bearings are investigated experimentally. The scope of the study includes optimizing the metallic dampers for maximum dissipation of energy, characterizing full-scale metallic dampers, and understanding the seismic behavior of a small-scale bridge with dampers. Three full-scale dampers, two of straight and one of linearly tapered rods, were fabricated and tested under a progressive cyclic load. Test results consistently show that the tangential stiffness of the metallic dampers does not degrade significantly as the number of loading cycles increases …


Using Flash Animations And 3d Rendering To Increase The Effectiveness Of Instructional Software, Timothy A. Philpot Jan 2001

Using Flash Animations And 3d Rendering To Increase The Effectiveness Of Instructional Software, Timothy A. Philpot

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Animation and three-dimensional rendering software offers exciting new capabilities that can enhance engineering instructional material. Using these software tools, instructional media can escape the static two-dimensional confines of the printed page or the classroom blackboard. This work-in-progress describes a project to develop instructional material for a Mechanics of Materials course. The paper presents examples of instructional animations, discusses software development tools used to create the animations and discusses early student reaction to the multimedia presentations


Fatigue Assessment Of Traffic Signal Mast Arms Based On Field Test Data Under Natural Wind Gusts, Genda Chen, Jingning Wu, Jiaqing Yu, Lokeswarappa R. Dharani, Michael G. Barker Jan 2001

Fatigue Assessment Of Traffic Signal Mast Arms Based On Field Test Data Under Natural Wind Gusts, Genda Chen, Jingning Wu, Jiaqing Yu, Lokeswarappa R. Dharani, Michael G. Barker

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In recent years, several states including Missouri, Wyoming, California, and Texas experienced fracture failures of traffic signal mast arms. Almost all the failures are associated with the propagation of defects or cracks. It is therefore imperative to evaluate existing mast arms using a simple yet accurate procedure. A statistical methodology is proposed to predict the fatigue life of signal mast arm structures on the basis of field-measured strain data. The annual occurrence of various stress levels is determined using the historical wind speed data in the vicinity of a mast arm structure and the strain readings of the structure under …


Simplified Window Glass Design Procedure, H. Scott Norville, Joseph E. Minor Dec 2000

Simplified Window Glass Design Procedure, H. Scott Norville, Joseph E. Minor

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper presents a simplified window glass design procedure (SWGDP) as an alternative to the comprehensive window glass design procedure described in ASTM E 1300, `Standard practice for determining the load resistance of glass in buildings.' Although ASTM E 1300 provides a technically robust treatment of the strength of window glass and window glass constructions, architects and engineers will find ASTM E 1300 difficult to use. The SWGDP presented herein uses the same failure prediction methodology to characterize the annealed window glass strength that underlies ASTM E 1300. By reducing the number of basic glass strength charts to one, the …


Design Methods For Auger Cip Piles In Compression, Giuliana A. Zelada, Richard Wesley Stephenson Dec 2000

Design Methods For Auger Cip Piles In Compression, Giuliana A. Zelada, Richard Wesley Stephenson

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This Paper Reports on a Study of 43 Compression Load Tests (Five Fully Instrumented) and Ten Pullout Tests of Auger Cast-In-Place (ACIP) Piles in Sand. Eight Design Methods Reported in the Literature Were Used to Predict the Measured Pile Capacities. Ultimate Load Capacities of the ACEP Load Tests Were Determined using Two Different Definitions of Ultimate Capacity and Compared with Predictions. Load Transfer Behavior Was Determined from a Study of the Fully Instrumented Pile Tests and Compared to Predicted Values. Recommendations Are Made Regarding the Design Approach Most Appropriate for These Foundations and the Best Procedure for Estimating Ultimate Capacity …


Rhizosphere Competitiveness Of Trichloroethylene-Degrading, Poplar-Colonizing Recombinant Bacteria, Hojae Shim, Sadhana Chauhan, Doohyun Ryoo, Kally Bowers, Stuart M. Thomas, Keith A. Canada, Thomas K. Wood, Joel Gerard Burken Nov 2000

Rhizosphere Competitiveness Of Trichloroethylene-Degrading, Poplar-Colonizing Recombinant Bacteria, Hojae Shim, Sadhana Chauhan, Doohyun Ryoo, Kally Bowers, Stuart M. Thomas, Keith A. Canada, Thomas K. Wood, Joel Gerard Burken

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Indigenous bacteria from poplar tree (Populus canadensis var. eugenei `Imperial Carolina') and southern California shrub rhizospheres, as well as two tree-colonizing Rhizobium strains (ATCC 10320 and ATCC 35645), were engineered to express constitutively and stably toluene o-monooxygenase (TOM) from Burkholderia cepacia G4 by integrating the tom locus into the chromosome. The poplar and Rhizobium recombinant bacteria degraded trichloroethylene at a rate of 0.8 to 2.1 nmol/min/mg of protein and were competitive against the unengineered hosts in wheat and barley rhizospheres for 1 month (colonization occurred at a level of 1.0 × 105 to 23 × 105 …


Simulation Of Temperature And Stress Fields During Rcc Dam Construction, Ronaldo Luna, Yongfu Wu Sep 2000

Simulation Of Temperature And Stress Fields During Rcc Dam Construction, Ronaldo Luna, Yongfu Wu

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The worldwide experience in the construction of roller-compacted concrete (RCC) dams together with the use of numerical solutions, allows the simulation of different scenarios in a computer. It is well documented that thermal control is one of the most important problems for RCC dam construction. The dam temperature changes due to the heat produced by the internal hydration of concrete and the environmental boundary conditions influencing the elastic modulus and creep properties of concrete. The construction process was simulated to study how the temperature and stress change during dam construction. The numerical methodology considers the effect of temperature on the …


Effects Of Ozone/Hydrogen Peroxide Pretreatment On Aerobic Biodegradability Of Nonionic Surfactants And Polypropylene Glycol, Mehmet Kitis, Craig D. Adams, John Kuzhikannil, Glen T. Daigger Jun 2000

Effects Of Ozone/Hydrogen Peroxide Pretreatment On Aerobic Biodegradability Of Nonionic Surfactants And Polypropylene Glycol, Mehmet Kitis, Craig D. Adams, John Kuzhikannil, Glen T. Daigger

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Studies were conducted which used the ozone/hydrogen peroxide (O3/H2O2) advanced oxidation process to pretreat three classes of compounds prior to aerobic biological treatment. The study compounds included ethylene oxide/propylene oxide (EO/PO) block copolymers, polypropylene glycols (PPGs), linear secondary alcoholethoxylates (LSAES), and alkylphenolethoxylates (APEs). After preoxidation with ozone and hydrogen peroxide (added at their stoichiometric ratio), 300 mg/L as COD samples were bioassayed in aerobic batch bioassays with a mixed liquor suspended solids concentration of 1500 mg/L. It was found that unoxidized polypropylated compounds (EO/PO block copolymers and PPGs) and LSAEs tended to be biorecalcitrant, …


Improving Shear Capacity Of Existing Rc T-Section Beams Using Cfrp Composites, Ahmed Khalifa, Antonio Nanni Jun 2000

Improving Shear Capacity Of Existing Rc T-Section Beams Using Cfrp Composites, Ahmed Khalifa, Antonio Nanni

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper presents the shear performance of reinforced concrete (RC) beams with T-section. Different configurations of externally bonded carbon fiber-reinforced polymer (CFRP) sheets were used to strengthen the specimens in shear. The experimental program consisted of six full-scale, simply supported beams. One beam was used as a benchmark and five beams were strengthened using different configurations of CFRP. The parameters investigated in this study included wrapping schemes, CFRP amount, 90°/0° ply combination, and CFRP end anchorage. The experimental results show that externally bonded CFRP can increase the shear capacity of the beam significantly. In addition, the results indicated that the …


Monitoring Precursor 16s Rrnas Of Acinetobacter Spp. In Activated Sludge Wastewater Treatment Systems, Daniel B. Oerther, Jakob Pernthaler, Andreas Schramm, Rudolf Amann, Lutgarde M. Raskin May 2000

Monitoring Precursor 16s Rrnas Of Acinetobacter Spp. In Activated Sludge Wastewater Treatment Systems, Daniel B. Oerther, Jakob Pernthaler, Andreas Schramm, Rudolf Amann, Lutgarde M. Raskin

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Recently, Cangelosi and Brabant used oligonucleotide probes targeting the precursor 16S rRNA of Escherichia coli to demonstrate that the levels of precursor rRNA were more sensitive to changes in growth phase than the levels of total rRNA (G. A. Cangelosi and W. H. Brabant, J. Bacteriol. 179:4457- 4463, 1997). In order to measure changes in the levels of precursor rRNA in activated sludge systems, we designed oligonucleotide probes targeting the 3' region of the precursor 16S rRNA of Acinetobacter spp. We used these probes to monitor changes in the level of precursor 16S rRNA during batch growth of Acinetobacter spp. …


Deformation In Concrete With External Cfrp Sheet Reinforcement, Joseph M. Tripi, Charles E. Bakis, Thomas E. Boothby, Antonio Nanni May 2000

Deformation In Concrete With External Cfrp Sheet Reinforcement, Joseph M. Tripi, Charles E. Bakis, Thomas E. Boothby, Antonio Nanni

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

A detailed experimental investigation of local and global deformations of tensile loaded, cracked, rectangular, concrete prisms reinforced with externally bonded carbon fiber reinforced polymer (CFRP) sheets was carried out. High and low modulus sheets were applied using three different thicknesses of epoxy interlayer between the sheet and concrete. It was found that the stiffness of the CFRP sheet had a dominant effect on global tension stiffening, whereas interlayer thickness had a dominant effect on local load transfer and damage formation. Thicker interlayers transferred load into through-cracked concrete over longer transfer zones, thereby increasing the spacing of subsequent cracks in the …


Destructive And Non-Destructive Testing Of Bridge J857 Phelps County, Missouri : Feasibility Study On Damage Detection Of Rc Structures Using Dynamic Signature Tests, Genda Chen, Xinbao Yang, Huimin Mu, Antonio Nanni Apr 2000

Destructive And Non-Destructive Testing Of Bridge J857 Phelps County, Missouri : Feasibility Study On Damage Detection Of Rc Structures Using Dynamic Signature Tests, Genda Chen, Xinbao Yang, Huimin Mu, Antonio Nanni

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This report presents the results of a research program aimed at investigating the constructability and effectiveness of externally bonded FRP strengthening systems for improving the flexural capacity of bridge decks and piers. The joint effort of two universities, industry, and a state DOT provided the premise for a successful outcome. Bridge J857 was constructed in 1932 and was scheduled for demolition in the fall of 1998 due to highway realignment. Two of the three solid reinforced concrete (RC) decks were strengthened using two FRP systems namely, near-surface mounted carbon FRP (CFRP) rods and surface bonded CFRP sheets. Bridge decks were …


Local Bond-Slip Relationship For Frp Reinforcement In Concrete, Francesco Focacci, Antonio Nanni, Charles E. Bakis Feb 2000

Local Bond-Slip Relationship For Frp Reinforcement In Concrete, Francesco Focacci, Antonio Nanni, Charles E. Bakis

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The objective of this paper is to define a rigorous numerical method to calibrate parameters of a given local bond-slip relationship using experimental results of pullout tests, taking into account the distribution of the slip and bond shear stress throughout the bar. The proposed method involves finding parameters of a given bond-slip relationship, such that results of pullout tests can be predicted in terms of applied pullout force and consequent slip at the loaded end and slip at the free end. The method is applied to some experimental data, and the results are discussed. For the application of the proposed …


Chemical Oxidation Of Mtbe Under O2-Rich And O2-Limited Environments Coupled With Biological Degradation Of Oxidation Byproducts, J. Sutherland, B. Panka, Craig D. Adams, Joel Gerard Burken Jan 2000

Chemical Oxidation Of Mtbe Under O2-Rich And O2-Limited Environments Coupled With Biological Degradation Of Oxidation Byproducts, J. Sutherland, B. Panka, Craig D. Adams, Joel Gerard Burken

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The H2O2/UV Advanced Oxidation Process (AOP) Was Investigated to Determine Byproduct Formation under Different Experimental Conditions (PH, Alkalinity, and H2O2/UV Dose). a Key Factor in the Efficiency of the AOP Was the Dissolved Oxygen Concentration. Gas Chromatography/mass Spectrometry (GC/MS) Analysis Was Used to Identify Byproducts Resulting from Oxidation under Oxygen-Rich and Oxygen-Limited Conditions. Resultant Oxidation Byproducts Were Analyzed for their Susceptibility to Biological Degradation. Biodegradation Rate Constants Were Determined and Modeled for the Primary Byproducts of the Advanced Oxidation Process. Inhibition Resulting from the Presence of Multiple Byproducts in a Biological System Was Investigated as Well. Effects of Process Parameters …


Degradation And Uptake Of Benzene In Laboratory Phytoremediation Studies, Carla Ross, Lisa M. Harrison, Adrian Marsh, Lars Zetterstrom, Joel Gerard Burken Jan 2000

Degradation And Uptake Of Benzene In Laboratory Phytoremediation Studies, Carla Ross, Lisa M. Harrison, Adrian Marsh, Lars Zetterstrom, Joel Gerard Burken

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In Whole-Plant Laboratory Studies, Hybrid Poplar Trees Were Shown to Impact a Variety of Fate and Transport Mechanisms for Benzene. Laboratory Experiments Investigated the Distribution of the Contaminant in the Plant Tissues, Degradation in the Soil Profile, and Volatilization from Both the Soil and Leaf Tissues. a New Testing System Was Developed that Allowed for Rapid Testing that is More Field-Representative Than Earlier Studies. Whole Plants Were Utilized in a Reactor Design that Included Both a Saturated and a Vadose Zone. the Continuous Feed Reactors Were Supplied with a Steady Influent Benzene Stream to Mimic Plume Conditions. the Presence of …


Applicability Of Ozone In Small Drinking Water Systems, Craig D. Adams, Justin Sutherland Jan 2000

Applicability Of Ozone In Small Drinking Water Systems, Craig D. Adams, Justin Sutherland

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The use of ozone in water treatment plants is expanding rapidly in the United States. Ozone offers excellent disinfection properties (including chlorine-resistant pathogens) and does not form trihalomethanes. Additionally, ozone can be used to achieve or control many other water quality parameters such as color, taste and odor, and inorganic and organic contaminant concentrations. Control of ozone's disinfection byproducts such as bromate (formed in high bromide waters) is required. This presentation will review the synergistic effects of ozone applicable to use in small water treatment plants.


Influence Of Hydration Temperature On Durability And Mechanical Property Performance Of Prestressed And Precast High-Performance Concrete Beams, John J. Myers, R. L. Carrasquillo Jan 2000

Influence Of Hydration Temperature On Durability And Mechanical Property Performance Of Prestressed And Precast High-Performance Concrete Beams, John J. Myers, R. L. Carrasquillo

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Concrete technology has continued to advance throughout the years to meet the demands of designers and innovative structural systems. With the advent of high-performance concrete (HPC), which contains large amounts of cementitious materials, the investigation of the impact of concrete temperature development during hydration on concrete performance is of keen interest. Match-curing technology was used to investigate the influence of concrete temperature development during hydration on the mechanical and material property performance of prestressed and precast HPC beams. These members were fabricated for use in two recently constructed HPC bridges in Texas. The investigation was conducted in conjunction with the …


Upgrading Missouri Transportation Infrastructure: Solid Reinforced-Concrete Decks Strengthened With Fiber-Reinforced Polymer Systems, T. Alkhrdaji, Antonio Nanni, R. Mayo Jan 2000

Upgrading Missouri Transportation Infrastructure: Solid Reinforced-Concrete Decks Strengthened With Fiber-Reinforced Polymer Systems, T. Alkhrdaji, Antonio Nanni, R. Mayo

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

More than 40 percent of the bridges in the United States need repair, strengthening, or replacement. Because of limited funds, many states are forced to post load restrictions on their bridges as a temporary measure. Recently, fiber-reinforced polymers (FRPs) have emerged as a practical solution for repair or strengthening of highway bridges. Since there are no nationally accepted specifications for design and construction with bonded FRP reinforcement, the Missouri Department of Transportation (MoDOT) has funded a research program aimed at validating the design and analysis procedure through strengthening and testing to failure of bridges under realistic highway loading and conditions. …