Civil Engineering Commons^™

Modal Perturbation Method For The Dynamic Characteristics Of Timoshenko Beams, Meng-Lin Lou, Quihua Duan, Genda Chen

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Timoshenko beams have been widely used in structural and mechanical systems. under dynamic loading, the analytical solution of a Timoshenko beam is often difficult to obtain due to the complexity involved in the equation of motion. In this paper, a modal perturbation method is introduced to approximately determine the dynamic characteristics of a Timoshenko beam. In this approach, the differential equation of motion describing the dynamic behavior of the Timoshenko beam can be transformed into a set of nonlinear algebraic equations. Therefore, the solution process can be simplified significantly for the Timoshenko beam with arbitrary boundaries. Several examples are given …

The Influence Of Ammonia And Carbon Dioxide On The Sorption Of A Basic Organic Pollutant To A Mineral Surface, Maneerat Ongwandee, Glenn Morrison, S. S. Bettinger

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Indoor surfaces have a sorptive capacity for organic pollutants which may be significantly influenced by other gases and the pH of the surface. in this research, we examine the influence of a common indoor gaseous acid, CO₂, and base, NH₃, on the adsorption of a volatile organic base, trimethylamine (TMA), to a mineral surface, zirconium silicate beads. Varying ammonia and CO₂ within concentration ranges of indoor relevance substantially influences the sorptive capacity of this mineral surface. Increasing the CO₂ mixing ratio to 1000 p.p.m. enhances surface capacity of TMA by 40-50%; increasing the NH3 …

Elastomer Reclaiming Composition And Method, Michael W. Rouse, Victor M. Deeb, Morgan L. White, Magdy Abdelrahman

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The present invention relates to elastomeric compositions and methods including compositions and methods involving the use of aromatic alcohols. The present invention further relates to elastomeric compositions that can include ground reclaimed elastomeric particles. Compositions of the present invention are usable in numerous elastomeric applications including interior and exterior vehicle parts, roofing, asphalt, and any other applications that employ an elastomer as an ingredient thereof, particularly those utilizing rubber or a similar elastomer.

The present invention further is directed to asphalt compositions and their methods of manufacture and use.

Comprehensive Evaluation Of Animated Instructional Software For Mechanics Of Materials, Timothy A. Philpot, Richard H. Hall

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

During the past three years, the Basic Engineering Department at the University of Missouri--Rolla has been developing a second-generation suite of instructional software called MecMovies for the mechanics of materials course. In the Fall 2003 semester, MecMovies was integrated into assignments throughout the entire semester for one of the six UMR mechanics of materials sections. This paper presents a comparison of student performance in the experimental section with student performance in five control sections along with discussion of student qualitative ratings and comments.

Deformation Analysis Of Missouri Bridge Approach Embankments, Jonathan L. Robison, Ronaldo Luna

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Missouri has recently experienced below expectation performance or "the bump-at-the-end of the bridge" phenomena at bridge approach slab transitions. Information on approach slab performance was collected state wide to assess if the problem was limited to regional or geological distribution. Finite element analysis was then used to explore the soil embankment-bridge structure differential settlement in two Missouri bridges; MoDOT Bridge A6031 in Livingston County, and MoDOT Bridge A5834 in Pulaski County. These two cases are indicative of the types of soil conditions encountered in the Northern Glaciated Plains region (deeper compressible foundation soils) and the Southern Ozarks region (shallow rocky …

Studies On The Use Of Carbon Waste Generated From Fertiliser Plant In Waste Water Treatment, Indra Deo Mall, Sanjay Tewari, Nripendra Singh

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Carbon waste generated from fertiliser plant has been used for adsorption studies for the removal of chromium, zinc and nickel and COD from industrial effluent from phenol formaldehyde plant, polyester plant, sugar plant. Removal to the extent of 91.40, 86.8, 93.8 percent was achieved at the initial concentration of 10 mg/1 for Cr(VI), Ni(TI) and Zn(II) respectively using carbon waste as adsorbent Removal of these metals were found to be in order of Zn(II) > Cr(VI) > Ni(II). In a multi cationic solution containing these three metals, Cr(VI) adsorbed preferentially over Ni(II) and Zn(II). COD removal of 67.51%, and 86.4 % was …

Utilisation Of Bagasse Fly Ash And Carbon Waste From Fertiliser Plant For Treatment Of Pyridine And 3-Picoline Bearing Wastewater, Indra Deo Mall, Sanjay Tewari, Nripendra Singh, Indra Mani Mishra

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The present work explores the possibility of utilizing sugarcane bagasse fly ash and carbon waste obtained from sugar mills and nitrogenous fertilizer plants, respectively for the removal of pyridine and 3-picoline from waste water. The adsorbing capacity of both adsorbents has been compared with that of activated carbon. Batch studies were conducted to see the effect of contact time, adsorbent dose, initial concentration and pH on the removal of pyridine and 3-picoline. Equilibrium data were fitted with Langmuir and Freundlich isotherms. Adsorptive capacities were found to be in the order: activated carbon > carbon waste > bagasse fly ash. Adsorption was found …

Rapid Measurement Of Indoor Mass-Transfer Coefficients, Glenn Morrison, Zhao Ping, Deborah J. Wiseman, Maneerat Ongwandee, Hong Chang, Julie Portman, Shekhar Regmi

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Indoor air pollutant concentrations can be influenced by how rapidly species are transported to and from surfaces. Consequently, a greater understanding of indoor transport phenomena to surfaces improves estimates of human exposure to indoor air pollutants. Here, we introduce two methods of rapidly and directly measuring species fluxes at indoor surfaces, allowing us to evaluate the transport-limited deposition velocity, v_t (a mass-transfer coefficient). The deposition velocity sensor (DeVS) method employs a small microbalance coated with a pure hydrocarbon, preferably octadecane. We quantify flux (or evaporation rate) of the hydrocarbon into a room by observing the rate of mass loss …

Multi-Probe Conductivity Method For Monitoring Time-Dependent Processes In Fresh Cementitious And Other Dense Slurry Systems, Pavate V. Trimbak, Kamal Khayat, Carmel Jolicoeur

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The invention provides a novel probe comprising multiple conductivity electrodes, which can be used to monitor various types of time-dependent processes in aqueous suspension, slurries, pastes, etc. for example, fresh cementitious materials, such as grouts, mortars and concrete. The processes which can be monitored as function of time through this novel method can be either "physical" or "chemical"; physical-type processes comprise settling, sedimentation, segregation, water migration, surface bleeding, channelling, etc.; chemical-type processes comprise dissolution or precipitation of solids, and any reactions involving the solution and solid phases present in the slurry.

Radionuclide Leaching From Residual Soils: Screening Study, Mark W. Fitch, Ellen England

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Four soil samples, collected from a National Priorities Listed site contaminated with uranium, thorium, and radium, were leached for two, seven, and 30 days. The nonleached soils, leached soils, and leachates were analyzed using gamma spectroscopy, alpha spectroscopy, and delayed neutron activation. Unleached and leached soils had low radionuclide activities, and four different leaching solutions had no significant observable effect upon the resulting leachate activity. Three of the soils produced leachates with uranium activities below the expected primary drinking water standard of 30 µg/L for uranium, but the leachate from the fourth soil had an unacceptably high concentration of uranium …

Forensic Investigation Of Failed Mast Arms Of Traffic Signal Supported Structures, Genda Chen, Michael G. Barker, D. Scott Mackenzie, Christopher W. Ramsay, Joe Alderson, Lokeswarappa R. Dharani, Jiaqing Yu

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In Missouri, 11 traffic signal mast arms fractured at the arm-post weld connection in 7 years. To reduce this fatigue failure, the Missouri Department of Transportation developed a fatigue-resistant weld profile that increases the weld leg and reduces the slope of the weld at the toe. This study investigated causes of the failed arms, compared performance of new and old weld profiles, and suggested retrofitting measures for further investigation. The scope included a metallurgical investigation of one failed field mast arm, laboratory fatigue testing of five prototype mast arms (two new and three old profiles), and laboratory failure analysis of …

Biotransformation Of Various Substituted Aromatic Compounds To Chiral Dihydrodihydroxy Derivatives, Henning Raschke, Michael Meier, Roland Hany, Markus D. Muller, Jan Roelof Van Der Meer, Hans-Peter E. Kohler, Joel Gerard Burken

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The biotransformation of four different classes of aromatic compounds by the Escherichia coli strain DH5α(pTCB 144), which contained the chlorobenzene dioxygenase (CDO) from Pseudomonas sp. strain P51, was examined. CDO oxidized biphenyl as well as monochlorobiphenyls to the corresponding cis-2,3-dihydro-2,3-dihydroxy derivatives, whereby oxidation occurred on the unsubstituted ring. No higher substituted biphenyls were oxidized. The absolute configurations of several monosubstituted cis-benzene dihydrodiols formed by CDO were determined. All had an S configuration at the carbon atom in meta position to the substituent on the benzene nucleus. with one exception, the enantiomeric excess of several 1,4-disubstituted cis-benzene dihydrodiols formed by CDO …

Concrete Roughness Characterization Using Laser Profilometry For Fiber-Reinforced Polymer Sheet Application, Norbert H. Maerz, Poornima Chepur, John J. Myers, Justin Linz

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The failure of a reinforced concrete member strengthened with fiberreinforced polymer (FRP) laminates may be caused by crushing of concrete, rupture of FRP laminates, or delamination of the FRP sheet. Therefore, the effectiveness and failure mode of FRP sheets applied to beams and columns is related to the degree of adhesion of the epoxy to the concrete surface. When a peeling or delamination failure can be avoided, a more effective engagement of the FRP sheet occurs, which results in more efficient use of the material. One of the principal factors affecting the bond behavior between the concrete and epoxy is …

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

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 …

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 …

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 × 10^{5 …}

Mechanism Of Interaction Of Asphalt Cement With Crumb Rubber Modifier, Magdy Abdelrahman, Samuel Carpenter

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The nature of the interaction process between asphalt cement and crumb rubber modifier (CRM) has not been fully understood. Two main types of mechanisms that affect the produced binder properties are reported: particle swelling and degradation (devulcanization and depolymerization). These mechanisms occur as the binder is subjected to different combinations of interaction time and temperature. Insight into the mechanisms by which the interaction between the two materials takes place through monitoring the changes in the rheological parameters of the binder is provided. The effects of the interaction process variables, time and temperature, are explained. The effect of CRM properties, including …

Displacement-Based Analysis And Design Of Rigid Retaining Walls During Earthquakes, Yingwei Wu

Doctoral Dissertations

"This research focused on the analysis and design of rigid retaining walls subjected to earthquakes and considered nonlinear foundation soil properties. The simultaneous sliding and rocking movements of retaining walls were considered. Seven field conditions, including moist, submerged, perched and saturated backfill with a sloping drain, were specified by design codes. A computer program capable of computing displacement using real time history records or equivalent sinusoidal motions was developed. Finally, a dynamic design procedure was proposed for practicing engineers.

The study revealed that maximum shear modulus in foundation soil, maximum ground acceleration, and soil nonlinearity had significant effect on the …

Expedient Method To Determine Active Zone Depth For Expansive Soils In The St. Louis, Missouri Area, Robert Allen Abbott

Masters Theses

"A laboratory testing program was developed to formulate a relationship which could be used to estimate the active zone depth at a given site with the index properties of the potentially expansive soils at the site. The testing program utilized standard consolidometers to incrementally add moisture to soil specimens to determine a swell versus soil suction index. Tests were performed on laboratory manufactured soil specimens of commercial clay to validate the testing methodology.

A QUATTRO PRO computer spreadsheet was developed to perform the calculations to determine the potential field surface heave for the soils tested provided they were at a …

Making Concrete Less Abstract, David Newton Richardson

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

CE 3 13 is a second level properties of concrete lecture course. In an effort to make it appear less abstract to the students, over the course of several semesters several learning strategies were tried, including journaling, muddiest point, entering the academy, role playing, bookends-on-a-lecture, and hands-on lab projects. Most recently, an emphasis on short writing-to-learn papers, a problems-based stance, and an integrated lab project was used. Student evaluations indicated that the lab projects and the increased writing was of significant benefit in promotion of learning.

Multiobjective Optimum Design Of Static And Seismic-Resistant Structures With Genetic Algorithm, Fuzzy Logic And Game Theory, Dan Li

Doctoral Dissertations

"The goal of this research is to develop a constrained multiobjective optimization method in the form of a robust, practical, problem-independent algorithm, and to investigate the effect of multiobjective optimization on structural design.

This research studies the properties and characteristics of multiobjective optimization and solutions. Design objectives, constraints and design variables as well as their effect on structural design and behaviors are investigated. Dynamic input energy for a multidegree-of-freedom structure is formulated. A multiobjective optimization algorithm based on game theory is developed. Fuzzy set theory is introduced to construct a fuzzy constrained environment. A Pareto genetic algorithm is developed based …

A New Chip-Set For Astra Digital Radio, Werner Bradinal, Christoph Moeller, Timothy A. Philpot, Mike Rose

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This chip-set provides the channel and source decoding functions for ASTRA Digital Radio (ADR) receivers. An overview of the system is given together with a summary of the main features of the ICs. The chip-set offers a flexible, but optimum solution to meet the requirements for low cost consumer sets.

Evaluation Of The Edge Strength Of Architectural Glass, Kevin L. Alexander

Opportunities for Undergraduate Research Experience Program (OURE)

A mechanical device to test the edge strength of glass was developed in a previous study and was to be modified for more accurate results in this study. The mechanical apparatus allows for a load to be applied and directed along one diagonal of a glass beam making the other diagonal the neutral axis. This allows only one edge to be in tension where the failure is desired.

This study evaluated the scored edge lines and the other edge lines of annealed glass which was cut by an experienced glass cutter with a steel scoring wheel, and a carbide scoring …

Design, Construction, Calibration And Applications Of An Apparatus Which Conducts The Large Missle Impact Test, John Schroeder

Opportunities for Undergraduate Research Experience Program (OURE)

Prior to Hurricane Andrew (August 1992), the South Florida Building Code maintained provisions for the design of building openings based on wind pressure only. Hurricane Andrew provided evidence of other failure modes, including windborne debris and internal pressure. Following the hurricane, several changes were made to building codes in South Florida. One addition requires building openings to resist windborne debris. A missile impact test incorporated into recently accepted Dade and Broward Counties editions of the South Florida Building Code states a window, door, or external protection device shall resist a prescribed number of impacts from a nine pound 2x4 timber …

Determination Of Aashto Layer Coefficients For Granular Materials By Use Of Resilient Modulus, David Newton Richardson

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The layer coefficients a₂ or a₃ for an unbound granular base or subbase material are found from a relationship with resilient modulus, E_b. The resilient modulus for a given material can be found by test using the "theta model" or by use of an estimation regression equation. E_b is a function of several factors, as discussed below.

Estimation Of Resilient Modulus Of Fine-Grained Subgrade Soils, David Newton Richardson

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

No abstract provided.

In-Plane/Out-Of-Plane Dynamic Racking Tests Of Curtain Wall Glass Elements, James H. Culp

Opportunities for Undergraduate Research Experience Program (OURE)

This report describes a research project that was conducted to examine architectural glass behavior as curtain wall components subjected to earthquake-like dynamic motions. The project was an extension of an earlier pilot study conducted in 1991. The 1991 pilot study dealt only with dynamic racking of the curtain wall in its own plane.

The focus of this study was to investigate the effects of adding out-of-plane motions to the previous in-plane motions and to observe the resulting structural performance of various types of architectural glass. Thus, the curtain wall specimens in the current study were racked with motion components both …

Stiffness Change Effects On Structure Control Systems, R. J. Falkenrath

Opportunities for Undergraduate Research Experience Program (OURE)

This paper contains the results of a computer analysis performed on a two-dimensional model structure, in which the structure response was found under dynamic loading conditions. A structural dynamics program (BASIC) was modified to perform its analysis on a two-dimensional structure with a control system modelled into it. The modified program was then used to determine whether a change in the stiffness of the structure would cause the control algorithm to be ineffective for the structure. In light of the limited scope of the analysis (two-dimensional model with constant applied force on one story), the results indicate that a control …

Time Characteristics Of Small Watersheds In Response To The Probable Maximum Precipitation, Brian Jay Swenty

Doctoral Dissertations

"The EPA Storm Water Management Model (SWMM) was used to perform single event simulations of Probable Maximum Precipitation (PMP) level rainfall events on the Loss Lake watershed in southcentral Missouri. Overland flow was simulated using kinematic wave routing and channel flow was simulated using dynamic wave routing.

Lag time was defined as the time between the centroid of the excess rainfall hyetograph and the centroid of the direct runoff hydrograph.

Rainfall depth, rainfall duration, and the distribution of rainfall intensity were found to be significant predictor variables for lag time. Defined as hydrologic parameters for this study, channel flow roughness, …