Open Access. Powered by Scholars. Published by Universities.®

Civil and Environmental Engineering Commons™

Open Access. Powered by Scholars. Published by Universities.®

Architecture

Missouri University of Science and Technology

Series

2008

Articles 1 - 10 of 10

Full-Text Articles in Civil and Environmental Engineering

Liquefaction Behavior Of Mississippi River Silts, Ali M. Izadi, Ronaldo Luna, Richard Wesley Stephenson Dec 2008

Liquefaction Behavior Of Mississippi River Silts, Ali M. Izadi, Ronaldo Luna, Richard Wesley Stephenson

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Civil Infrastructure Built on Alluviums and Recent Deposits, Such as Dams, Contain Significant Amount of Silts. the Static and Dynamic Behavior of These Fine-Grained Soils Has Been Investigated Less Than the Clay-Like or Sand-Like Soils. Low Plasticity Silts (PI = 6) Obtained East of St. Louis in Illinois Are Known as Loess that Has Been Re-Deposited by Water in the Floodplains of the Mississippi River. These Silts Were Reconstituted in the Laboratory by Slurry at Water Content above the Liquid Limit and Then Consolidated to an Initial Effective Stress. the Initial Laboratory Characterization under Monotonic Loading Included a Series of …

Go to article

Piles Under Earthquake Loads, Shamsher Prakash, Vijay K. Puri Dec 2008

Piles Under Earthquake Loads, Shamsher Prakash, Vijay K. Puri

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Piles are preferred type of foundation for supporting structures in seismic areas. their performance is affected by soil, pile and earthquake related parameters. in non-liquefying soils, the shear modulus may degrade, and material damping may increase with increasing strain/displacement. in liquefying soils, the lateral ground displacement may lead to increased lateral loads and moments on the pile leading to pile failure in bending. the loss of lateral support can also lead to buckling type failure. These issues for pile design in seismic areas are examined. © 2008 ASCE.

Go to article

Fresh Self Compacting Concrete, A Shear Thickening Material, Dimitri Feys, Ronny Verhoeven, Geert De Schutter Jul 2008

Fresh Self Compacting Concrete, A Shear Thickening Material, Dimitri Feys, Ronny Verhoeven, Geert De Schutter

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In Literature, the Rheological Properties of Concrete Have Been Investigated Thoroughly, resulting in a Simple Description, in Steady State, by Means of the Bingham Model. Self-Compacting Concrete Shows a Lower Yield Stress, Which in Some Cases is Very Close to Zero, or Can Even Appear to Be Negative When Extrapolating the Bingham Model. in the Latter Case, the Bingham Model is Not Valid and Other Solutions Must Be Found. in This Paper, the Non-Linearity - or Shear Thickening - in the Rheological Behavior of Fresh SCC is Described with the Modified Bingham Model, after the Elimination of Possible Measurement Artefacts. …

Go to article

Effects Of Ionic Strength, Temperature, And Ph On Degradation Of Selected Antibiotics, Keith A. Loftin, Craig D. Adams, Michael T. Meyer, Rao Surampalli Mar 2008

Effects Of Ionic Strength, Temperature, And Ph On Degradation Of Selected Antibiotics, Keith A. Loftin, Craig D. Adams, Michael T. Meyer, Rao Surampalli

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Aqueous degradation rates, which include hydrolysis and epimerization, for chlorretracycline (CTC), oxytetracycline (OTC), tetracycline (TET), lincomycin (LNC), sulfachlorpyridazine (SCP), sulfadimethoxine (SDM), sulfathiazole (STZ), trimethoprim (TRM), and tylosin a (TYL) were studied as a function of ionic strength (0.0015, 0.050, or 0.084 mg/L as Na2HPO4), temperature (7, 22, and 35°C), and pH (2, 5, 7, 9, and 11). Multiple linear regression revealed that ionic strength did not significantly affect (α = 0.05) degradation rates for all compounds, but temperature and pH affected rates for CTC, OTC, and TET significand (α = 0.05). Degradation also was observed for TYL at pH 2 …

Go to article

Review Of Design Guidelines For Frp Confinement Of Reinforced Concrete Columns Of Noncircular Cross Sections, Silvia Rocca, Nestore Galati, Antonio Nanni Jan 2008

Review Of Design Guidelines For Frp Confinement Of Reinforced Concrete Columns Of Noncircular Cross Sections, Silvia Rocca, Nestore Galati, Antonio Nanni

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Current international design guidelines provide predictive design equations for the strengthening of reinforced concrete (RC) columns of both circular and prismatic cross sections by means of fiber-reinforced polymer (FRP) confinement and subjected to pure axial loading. Extensive studies (experimental and analytical) have been conducted on columns with circular cross sections, and limited studies have been conducted on members with noncircular cross sections. in fact, the majority of available research work has been on small-scale, plain concrete specimens. in this review paper, four design guidelines are introduced, and a comparative study is presented. This study is based on the increment of …

Go to article

Extension Of The Poiseuille Formula For Shear-Thickening Materials And Application To Self-Compacting Concrete, Dimitri Feys, Ronny Verhoeven, Geert De Schutter Jan 2008

Extension Of The Poiseuille Formula For Shear-Thickening Materials And Application To Self-Compacting Concrete, Dimitri Feys, Ronny Verhoeven, Geert De Schutter

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In Practice, While Placing Concrete in a Formwork by Pumping, the Pressure Generated by the Pump is Not Controlled. in Order to Enhance the Safety on the Worksite, and in View of the Current Economic and Ecologic Arguments, It Would Be Useful to Dispose of an Equation Able to Predict Pressure Losses based on the Rheological Properties of the Concrete and the Pipe Configuration. This Paper Describes the Derivation of an Extended Version of the Poiseuille Formula, for Shear-Thickening Materials with a Yields Stress, Described by the Modified Bingham Equation. This Formula is Applied to Flow-Tests with Self-Compacting Concrete. the …

Go to article

Kinetics And Reaction Products Of Ozone And Surface-Bound Squalene, J. R. Wells, Glenn Morrison, Beverly K. Coleman Jan 2008

Kinetics And Reaction Products Of Ozone And Surface-Bound Squalene, J. R. Wells, Glenn Morrison, Beverly K. Coleman

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Because of the high occupant density in aircraft, the surface chemistry of ozone and squalene, an important component of skin oil, was evaluated. a reaction probability of 45±14) x 10 -5 was determined for the reaction of squalene (2,6,10,15,19,23-hexamethyl-2,6,10,14,18,22- tetracosahexaene) with ozone (50 parts per billion (ppb)) on a glass plate surface using the Field and Laboratory Emission Cell (FLEC) Automation and Control System (FACS). to more clearly define part of squalene's indoor environment degradation mechanism, gas-phase and surface-bound products of the squalene+O3 reaction were also investigated. Emitted products were captured in solution, derivatized with O-(2,3,4,5,6pentafluorobenzyl) hydroxylamine (PFBHA), and analyzed …

Go to article

Modeling The Fate Of Pharmaceuticals And Personal Care Products In Sewage Treatment Plants, Craig D. Adams Jan 2008

Modeling The Fate Of Pharmaceuticals And Personal Care Products In Sewage Treatment Plants, Craig D. Adams

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Chemical fate models can be used to estimate the transformation reactions and the partitioning behavior of pharmaceuticals and personal care products (PPCPs) in sewage treatment plants (STPs). Modeling the fate of PPCPs in a STP requires parameters such as rate constants or partition coefficients that are often unique to a specific STP, and that may exhibit significant temporal variability. Chemical fate models provide both a valuable test of our understanding of the fundamental underlying mechanisms regarding the fate of PPCPs in STPs, as well as a means of providing both qualitative and quantitative estimates for PPCP removal. This paper is …

Go to article

Sustainable Lunar Habitat Protection Against Damage By Meteoroid Impacts, William P. Schonberg, Robin Putzar, Frank Schaefer Jan 2008

Sustainable Lunar Habitat Protection Against Damage By Meteoroid Impacts, William P. Schonberg, Robin Putzar, Frank Schaefer

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Sustainability is a key consideration in the design and establishment of human habitats on the Moon (and on Mars as well). One hazard faced by such habitats is the damage that can be caused by the impact of a meteoroid on a critical habitat structure or structural component. in this paper we discuss various approaches to meteoroid shielding for lunar habitats, focusing on approaches that use resources mined or extracted from the moon. Advantages and disadvantages of these various techniques are also presented and discussed. the Moon's mineralogy is highlighted, and suggestions are presented for materials that can be used …

Go to article

Forecasting Model For Air Taxi, Commercial Airline, And Automobile Demand In The United States, Hojong Baik, Antonio A. Trani, Nicolas Hinze, Howard Swingle, Senanu Ashiabor, Anand Seshadri Jan 2008

Forecasting Model For Air Taxi, Commercial Airline, And Automobile Demand In The United States, Hojong Baik, Antonio A. Trani, Nicolas Hinze, Howard Swingle, Senanu Ashiabor, Anand Seshadri

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

A nationwide model predicts the annual county-to-county person roundtrips for air taxi, commercial airline, and automobile at 1-year intervals through 2030. the transportation systems analysis model (TSAM) uses the four-step transportation systems modeling process to calculate trip generation, trip distribution, and mode choice for each county origin-destination pair. Network assignment is formulated for commercial airline and air taxi demand. TSAM classifies trip rates by trip purpose, household income group, and type of metropolitan statistical area from which the round-trip started. a graphical user interface with geographic information systems capability is included in the model. Potential applications of the model are …

Go to article