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Full-Text Articles in Architectural Engineering

Fenestration Studies On Building Energy Using The Facade Evaluation Facility, Wendell Cocina Dec 2011

Fenestration Studies On Building Energy Using The Facade Evaluation Facility, Wendell Cocina

UNLV Theses, Dissertations, Professional Papers, and Capstones

The project was developed to assess several types of facades and their influence on building energy, mainly focused on windows and other building fenestrations. Requirements for the facility are stated in this paper alongside corresponding solutions. The facility is designed to represent a section of a building façade. Experimenting on a wide range of fenestrations including windows with integrated PV elements was the primary prerequisite. The option of removable façade configurations was used and allowed testing specimens to be changed effortlessly. Instrumentation and data acquisition are discussed including calibration and uncertainty analysis. Investigation of the air conditioning unit was concluded …


Longitudinal Evaluation Of A Gis Laboratory In A Transportation Engineering Course, Ghulam H. Bham, Dan Cernusca, Ronaldo Luna, Uday R.R. Manepalli Oct 2011

Longitudinal Evaluation Of A Gis Laboratory In A Transportation Engineering Course, Ghulam H. Bham, Dan Cernusca, Ronaldo Luna, Uday R.R. Manepalli

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper focuses on the potential impact of student-centered feedback for enhancing the learning experience of civil engineering students that used a geographic information system (GIS) based tutorial in a transportation engineering course. the tutorial was implemented in a laboratory environment developed as a self-guided activity supported by a web-Based learning system. the formative research proposed in this study includes a series of four successive implementations of this laboratory. Students' performance, beliefs, and perceptions were monitored by using a mixed methods design approach and weaknesses identified from early implementations were addressed before the next implementation of the laboratory activity. the …


Monitoring The Early-Age Hydration Of Self-Compacting Concrete Using Ultrasonic P-Wave Transmission And Isothermal Calorimetry, Bram Desmet, Kelly Chrysanthe Atitung, Miguel Angel Abril Sanchez, John Vantomme, Dimitri Feys, Nicolas Robeyst, Katrien Audenaert, Geert De Schutter, Veerle Boel, Gert Heirman, Özlem Cizer, Lucie Vandewalle, Dionys Van Gemert Oct 2011

Monitoring The Early-Age Hydration Of Self-Compacting Concrete Using Ultrasonic P-Wave Transmission And Isothermal Calorimetry, Bram Desmet, Kelly Chrysanthe Atitung, Miguel Angel Abril Sanchez, John Vantomme, Dimitri Feys, Nicolas Robeyst, Katrien Audenaert, Geert De Schutter, Veerle Boel, Gert Heirman, Özlem Cizer, Lucie Vandewalle, Dionys Van Gemert

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Early-Age Hydration (B48 H) of a Series of Self-Compacting Concretes and Corresponding Mortars and One Traditionally Vibrated Concrete and Mortar is Monitored in a Continuous Way using Ultrasonic Testing and Isothermal Calorimetry. the Mixtures Differ in Type of Mineral Addition, Superplasticizer, Cement, Cement-To-Powder Ratio and Water-To-Powder Ratio. the Influence of These Different Mixture Compositions on the Kinetics of the Hydration during the First Days of the Hydration is Characterized by the Heat Production Rate Q and the Evolution of the P-Wave Velocity, which is a Consequence of the Microstructural Changes. the Variations in the Acceleration Caused by Mineral Additions …


Direct Shear Tests On Jsc-1a Lunar Regolith Simulant, Masafumi Iai, Ronaldo Luna Oct 2011

Direct Shear Tests On Jsc-1a Lunar Regolith Simulant, Masafumi Iai, Ronaldo Luna

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

A series of direct shear tests were conducted on the JSC-1A lunar regolith simulant in a 101.6-mm- (4-in.-) diameter container. the direct shear test provides a unique mode of failure that aids the development of excavation tools for the Moon. Relative density and normal load were varied to study the strength behavior of such granular material at peak and critical state conditions. the values of the internal friction angle ranged from 30 to 70. a relationship between the internal friction angle of the direct shear and the published triaxial compression test results is presented. Additionally, the measured dilatancy angle is …


Remote Sensing Of Soil Moisture Using Airborne Hyperspectral Data, Michael Finn, Mark Lewis, David Bosch, Mario Giraldo, Kristina Yamamoto, Dana Sullivan, Russell Kincaid, Ronaldo Luna, Gopala Allam, Craig Kvien, Michael Williams Oct 2011

Remote Sensing Of Soil Moisture Using Airborne Hyperspectral Data, Michael Finn, Mark Lewis, David Bosch, Mario Giraldo, Kristina Yamamoto, Dana Sullivan, Russell Kincaid, Ronaldo Luna, Gopala Allam, Craig Kvien, Michael Williams

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Landscape assessment of soil moisture is critical to understanding the hydrological cycle at the regional scale and in broad-scale studies of biophysical processes affected by global climate changes in temperature and precipitation. Traditional efforts to measure soil moisture have been principally restricted to in situ measurements, so remote sensing techniques are often employed. Hyperspectral sensors with finer spatial resolution and narrow band widths may offer an alternative to traditional multispectral analysis of soil moisture, particularly in landscapes with high spatial heterogeneity. This preliminary research evaluates the ability of remotely sensed hyperspectral data to quantify soil moisture for the Little River …


Phytoscreening For Chlorinated Solvents Using Rapid In Vitro Spme Sampling: Application To Urban Plume In Verl, Germany, Matt A. Limmer, Jean Christophe Balouet, Frank Karg, Don A. Vroblesky, Joel Gerard Burken Oct 2011

Phytoscreening For Chlorinated Solvents Using Rapid In Vitro Spme Sampling: Application To Urban Plume In Verl, Germany, Matt A. Limmer, Jean Christophe Balouet, Frank Karg, Don A. Vroblesky, Joel Gerard Burken

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Rapid Detection and Delineation of Contaminants in Urban Settings is Critically Important in Protecting Human Health. Cores from Trees Growing above a Plume of Contaminated Groundwater in Verl, Germany, Were Collected in 1 Day, with Subsequent Analysis and Plume Mapping Completed over Several Days. Solid-Phase Microextraction (SPME) Analysis Was Applied to Detect Tetrachloroethene (PCE) and Trichloroethene (TCE) to Below Nanogram/liter Levels in the Transpiration Stream of the Trees. the Tree Core Concentrations Showed a Clear Areal Correlation to the Distribution of PCE and TCE in the Groundwater. Concentrations in Tree Cores Were Lower Than the Underlying Groundwater, as Anticipated; However, …


The Bridge Newsletter Winter 2011, Missouri University Of Science And Technology Oct 2011

The Bridge Newsletter Winter 2011, Missouri University Of Science And Technology

The Bridge Newsletter

-Living intentionally: Meet the Oerthers
-Making a lasting impact
-Phytoforensics
-The simple things of life


Modern Protection Systems To Prevent Corrosion Of Structural Steel Elements Due To Deicing And Roadway Salts, John J. Myers, Wei Zheng Sep 2011

Modern Protection Systems To Prevent Corrosion Of Structural Steel Elements Due To Deicing And Roadway Salts, John J. Myers, Wei Zheng

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The effectiveness of innovative polymeric coatings, polyurea and Poly aspartic polyurea, to protect structural steel from corrosion was investigated through standard laboratory tests. the coating evaluation tests included salt fog test, QUV weathering test, adhesion test, and freeze-thaw stability test. These tests were used to assess the long-term performance of coating technologies compared to the conventional polyurethane type coatings, i.e. coating systems with inorganic zinc primer, epoxy intermediate coat and polyurethane topcoat. This paper presents part of results in the aforementioned evaluation tests. the results illustrate that Poly aspartic coating systems are very promising for corrosion mitigation and can provide …


Correction Factors For An Analytical Method Of Pile Foundation Response Subjected To Horizontal Dynamic Vibrations, Domenica Cambio, Louis Ge Sep 2011

Correction Factors For An Analytical Method Of Pile Foundation Response Subjected To Horizontal Dynamic Vibrations, Domenica Cambio, Louis Ge

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In pile foundation response due to horizontal vibration, it is known that the original Novak's method overestimates the dominant frequency and underestimates the dominant amplitude of pile head responses. It is found that reducing the pile-foundation system stiffness and damping coefficients would lead to a smaller dominant frequency and higher dominant amplitude, respectively. the objective of this paper is to evaluate and determine appropriate correction factors for stiffness and damping coefficients for the analytical model developed by Novak and El-Sharnouby (1983) to improve the theoretical predictions of pile foundations subjected to dynamic forces. the reduction factors were determined by continuously …


Accelerated Construction For Pedestrian Bridges: A Comparison Between High Strength Concrete (Hsc) And High-Strength Self Consolidating Concrete (Hs-Scc), John J. Myers, Kurt Bloch Sep 2011

Accelerated Construction For Pedestrian Bridges: A Comparison Between High Strength Concrete (Hsc) And High-Strength Self Consolidating Concrete (Hs-Scc), John J. Myers, Kurt Bloch

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

High-strength concrete (HSC) and glass fiber reinforced polymer (GFRP) bars are materials utilized in bridge construction to lower cost, reduce construction time, and increase service life of bridge structures. Recently, high-strength self-consolidating concrete (HS-SCC), a highly flowable concrete that does not require vibration, has been developed as a viable alternative to HSC for use in situations with congested steel or a need for rapid construction. Coupling HS-SCC with GFRP bars could create durable structures built rapidly. Several performance related issues remain to be investigated such as the behavior of prestress loss, shear, creep, shrinkage, thermal gradients, mechanical property development, time …


Earthquake-Induced Deformation Analysis Of A Bridge Approach Embankment In Missouri, W. Liu, Ronaldo Luna, Richard Wesley Stephenson, S. Wang Sep 2011

Earthquake-Induced Deformation Analysis Of A Bridge Approach Embankment In Missouri, W. Liu, Ronaldo Luna, Richard Wesley Stephenson, S. Wang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Earthquake-Induced Deformations for a Bridge Approach Earth Embankment Are Predicted using a Calibrated Numerical Model. the Constitutive Soil Model is a Modified Hyperbolic Model that Uses Masing Rules and Incremental Pore Pressure Relations. the Model Was Calibrated using Both Laboratory and Field Data. a Shaking Table Physical Model Was Used to Verify the Numerical Simulation. Additionally, the Upper San Fernando Dam Was Modeled to Reproduce the Deformations in the 1971 Earthquake. the Subsurface and Embankment Soil Conditions Were Characterized using Field and Laboratory Methods. the Model Developed Was Used to Predict the Earthquake-Induced Deformations of an Approach Embankment to Bridge …


Influence Of Geotechnical Dataset On The Range Of Influence Of Undrained Shear Strength, Site Onyejekwe, Louis Ge Aug 2011

Influence Of Geotechnical Dataset On The Range Of Influence Of Undrained Shear Strength, Site Onyejekwe, Louis Ge

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The knowledge of the spatial variability of geotechnical parameters, which can be described statistically by the mean, the variance, and the scale of fluctuation, is important in reliability-Based design. of particular importance is the scale of fluctuation. It can be used to compute the variance reduction factor, a factor of spatial averaging of geotechnical properties to reduce their point variance. the most prevalent method of determining the scale of fluctuation uses datasets whose data points are at close and regular intervals, e.g. measurements from cone penetrometer soundings. Another method, when continuous measurements are not available, uses datasets that are widely …


Special Issue On The 6th International Phytotechnologies Conference, St. Louis, Missouri, 2009: Conference Review, Joel G. (Gerard) Burken, Jason C. White Aug 2011

Special Issue On The 6th International Phytotechnologies Conference, St. Louis, Missouri, 2009: Conference Review, Joel G. (Gerard) Burken, Jason C. White

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

No abstract provided.


Arsenic Accumulation In Rice Grains: Effects Of Cultivars And Water Management Practices, Bin Hua, Wengui Yan, Jianmin Wang, Baolin Deng, John Yang Aug 2011

Arsenic Accumulation In Rice Grains: Effects Of Cultivars And Water Management Practices, Bin Hua, Wengui Yan, Jianmin Wang, Baolin Deng, John Yang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Arsenic (As) accumulation in rice grains is a threat to human health and marketability of rice products. in an effort to minimize as uptake by rice grains, field experiments were conducted to investigate as accumulation in rice grains of three cultivars in monosodium methane arsonate-treated soil under saturated and flooded water management practices. Results indicated that as concentrations in rice grains were cultivar-dependent and influenced by water management. Soil flooding would substantially enhance the as accumulation with a great variation among cultivars. Extractable as in the soil was positively correlated with sodium dithionite-sodium citrate-sodium bicarbonate solution-extractable Fe, suggesting a strong …


Numerical Modeling Of Aquaculture Dissolved Waste Transport In A Coastal Embayment, Subhas K. Venayagamoorthy, Hyeyun Ku, Oliver B. Fringer, Alice Chiu, Rosamond L. Naylor, Jeffrey R. Koseff Aug 2011

Numerical Modeling Of Aquaculture Dissolved Waste Transport In A Coastal Embayment, Subhas K. Venayagamoorthy, Hyeyun Ku, Oliver B. Fringer, Alice Chiu, Rosamond L. Naylor, Jeffrey R. Koseff

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Marine aquaculture is expanding rapidly without reliable quantification of effluents. The present study focuses on understanding the transport of dissolved wastes from aquaculture pens in near-coastal environments using the hydrodynamics code SUNTANS (Stanford Unstructured Nonhydrostatic Terrain-following Adaptive Navier-Stokes Simulator), which employs unstructured grids to compute flows in the coastal ocean at very high resolution. Simulations of a pollutant concentration field (in time and space) as a function of the local environment (bathymetry), flow conditions (tides and wind-induced currents), and the location of the pens were performed to study their effects on the evolution of the waste plume. The presence of …


Phytoforensics, Dendrochemistry, And Phytoscreening: New Green Tools For Delineating Contaminants From Past And Present, Joel Gerard Burken, Don A. Vroblesky, Jean Christophe Balouet Aug 2011

Phytoforensics, Dendrochemistry, And Phytoscreening: New Green Tools For Delineating Contaminants From Past And Present, Joel Gerard Burken, Don A. Vroblesky, Jean Christophe Balouet

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

As Plants Evolved to Be Extremely Proficient in Mass Transfer with their Surroundings and Survive as Earth's Dominant Biomass, They Also Accumulate and Store Some Contaminants from Surroundings, Acting as Passive Samplers. Novel Applications and Analytical Methods Have Been Utilized to Gain Information About a Wide Range of Contaminants in the Biosphere Soil, Water, and Air, with Information Available on Both Past (Dendrochemistry) and Present (Phytoscreening). Collectively These Sampling Approaches Provide Rapid, Cheap, Ecologically Friendly, and overall "Green" Tools Termed "Phytoforensics". © 2011 American Chemical Society.


Implementation And Testing Of Rans Turbulence Models For Stably Stratified Flows, Zachary A. Elliott, S. K. Venayagamoorthy Jul 2011

Implementation And Testing Of Rans Turbulence Models For Stably Stratified Flows, Zachary A. Elliott, S. K. Venayagamoorthy

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The presence of buoyancy forces due to stratification has a substantial effect on the flow development and mixing processes and hence influences the distribution of pollutants and suspended matter in environmental flows such as in reservoirs, lakes, and estuaries. In this study, we focus on the implementation and testing of proposed changes that explicitly account for buoyancy effects in Reynolds-averaged Navier-Stokes (RANS) turbulence models. Direct numerical simulation (DNS) data of stably stratified homogeneous turbulence are used to study the parameters in two-equation RANS turbulence models such as the buoyancy parameter Cε3, and the turbulent Prandtl number Prt in the k-ε …


A Slurry Consolidation Approach To Reconstitute Low-Plasticity Silt Specimens For Laboratory Triaxial Testing, Shuying Wang, Ronaldo Luna, Richard Wesley Stephenson Jul 2011

A Slurry Consolidation Approach To Reconstitute Low-Plasticity Silt Specimens For Laboratory Triaxial Testing, Shuying Wang, Ronaldo Luna, Richard Wesley Stephenson

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Silt Specimen Reconstitution using a Slurry Consolidation Approach is Commonly Used for Laboratory Testing. This Paper Presents a New Slurry Consolidation Approach to Reconstitute Silt Specimens for Use in Triaxial Testing. Silt Specimens Were Reconstituted in a Split Vacuum Mold Mounted on a Special Experimental Setup. the Uniformity of the Reconstituted Specimens Was Verified by Measuring the Water Content and Grain Size Distribution throughout the Specimens. the Testing Program Was Expedited using a Special Sample Handling Technique to Move the Specimen from the Special Experimental Setup to the Triaxial Chamber Base Platen. the Handling Process Did Not Disturb the Specimens …


In-Plane Cyclic Shear Performance Of Interlocking Compressed Earth Block Walls, David William Bland Jun 2011

In-Plane Cyclic Shear Performance Of Interlocking Compressed Earth Block Walls, David William Bland

Master's Theses

This thesis presents results from testing of interlocking compressed earth block (CEB) masonry shear walls.  CEBs are low strength earth masonry units sometimes stabilized with cement or lime.  The interlocking compressed earth blocks (ICEBs) used in this experiment are dry stacked interlocking hollow units, which can be reinforced and grouted after they are laid.  Although significant research has been undertaken to optimize the material properties of CEBs, little has been done to investigate the performance of structural systems currently being built using this technology.

Test results are reported for three 1800 mm x 1800 mm wall specimens constructed with cement …


Spatial Variation And Correlation Between Undrained Shear Strength And Plasticity Index, Xin Kang, Site Onyejekwe, Louis Ge, Richard Wesley Stephenson May 2011

Spatial Variation And Correlation Between Undrained Shear Strength And Plasticity Index, Xin Kang, Site Onyejekwe, Louis Ge, Richard Wesley Stephenson

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

A Soil Variability Analysis is Presented in This Paper. About 317 Unconsolidated Undrained Triaxial Compression Tests (UU) Were Carried Out on Undisturbed Samples from Four Locations in Missouri. the Spatial Variation of the Undrained Shear Strength and Plasticity Index Was Described by the Second-Moment Statistics (Mean and Variance). Meanwhile, the Correlation between the Undrained Shear Strength and Plasticity Index Was Established and Compared with Other Published Empirical Equations. the Results from the Soil Variability Analysis Provide a Framework to the Reliability-Based Design. © 2011 ASCE.


Effectiveness Of Objective Functions In Soil Model Calibration Through Numerical Optimization, Michelle Deng, Louis Ge May 2011

Effectiveness Of Objective Functions In Soil Model Calibration Through Numerical Optimization, Michelle Deng, Louis Ge

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

When a conventional method such as linear regression is insufficient to identify the constants and parameters of an advanced constitutive model, numerical optimization techniques are often being used. in employing numerical optimization to constitutive model calibration, an objective function essentially needs to be formulated in such way that the difference between the measured and computed data points is quantified. When a minimum value of the objection function is obtained, the corresponding variables are the optimized model constants and parameters. in this paper, a modified Cam-Clay model is calibrated against laboratory data. Three objective functions are proposed in different forms to …


Variability Analysis Of Undrained Shear Strength For Reliability-Based Design, Site Onyejekwe, Xin Kang, Louis Ge, Richard Wesley Stephenson May 2011

Variability Analysis Of Undrained Shear Strength For Reliability-Based Design, Site Onyejekwe, Xin Kang, Louis Ge, Richard Wesley Stephenson

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Description of the Spatial Variation of Compositional and Mechanical Soil Parameters is Often Paramount in Site Characterization of Geotechnical Design and Analysis. the Values of the Parameters Themselves Largely Depend on In-Situ State Factors Which Are Related to Spatial Locations. Also, for Large-Scale Engineering Projects Such as Earth Dams or Highways, It is Generally Expected that Heterogeneous Site Characteristics Will Be Revealed by Investigations at Spatially Distant Locations. Currently, Most Reliability-Based Design Methods Are based on the Second-Moment Statistics (Mean and Variance). However, They Are Unable to Adequately Describe the Spatial Variation of Soil Properties. in This Paper, Spatial Correlation …


A Virtual Supply Airflow Rate Meter In Rooftop Air Conditioning Units, Daihong Yu May 2011

A Virtual Supply Airflow Rate Meter In Rooftop Air Conditioning Units, Daihong Yu

Durham School of Architectural Engineering and Construction: Dissertations, Theses, and Student Research

Virtual sensing technology aims to estimate difficult to measure, expensive, or new quantities by using multifarious mathematical models along with non-invasive and low-cost measurements. Such embedded intelligence is a key to improving the performance of building systems in terms of functionality, safety, energy efficiency, environmental impacts, and costs. Considering the progress that has been achieved over many various fields (e.g., process controls, automobiles, avionics, autonomous robots, telemedicine) within the last two decades, numerous intelligent features have been incorporated and enabled that would otherwise not be possible or economical.

To identify the potential opportunities and research/development needs of virtual sensing technology …


Surface Reaction Rate And Probability Of Ozone And Alpha-Terpineol On Glass, Polyvinyl Chloride, And Latex Paint Surfaces, Shi Shu, Glenn Morrison May 2011

Surface Reaction Rate And Probability Of Ozone And Alpha-Terpineol On Glass, Polyvinyl Chloride, And Latex Paint Surfaces, Shi Shu, Glenn Morrison

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Ozone can react homogeneously with unsaturated organic compounds in buildings to generate undesirable products. However, these reactions can also occur on indoor surfaces, especially for low-volatility organics. Conversion rates of ozone with α-terpineol, a representative low-volatility compound, were quantified on surfaces that mimic indoor substrates. Rates were measured for α-terpineol adsorbed to beads of glass, polyvinylchloride (PVC), and dry latex paint, in a plug flow reactor. a newly defined second-order surface reaction rate coefficient, k2, was derived from the flow reactor model. the value of k2 ranged from 0.68 - 10-14 cm 4s-1molecule-1 for α-terpineol adsorbed to PVC to 3.17 …


How Much Do U.S. University Students Know, And Want To Know, About Sustainability And Green Building? The Findings Of A Survey, And Possible Implications For General Elective Curricula., Jeremy R. Farner May 2011

How Much Do U.S. University Students Know, And Want To Know, About Sustainability And Green Building? The Findings Of A Survey, And Possible Implications For General Elective Curricula., Jeremy R. Farner

Purdue Polytechnic Masters Theses

Using the survey approach, this investigation examined the attitudes and interest of college students at two universities in different geographic locations within the United States.  Approximately 24,000 students from all disciplines and majors at Weber State University (WSU) in Utah, and 4,000 at Purdue University in Indiana, were invited to participate in a study to determine current knowledge, familiarity, and interest in topics within the sustainability and Green Building educational arena. The goal of this study was to determine what students already know, would like to know, and how much interest there would be in developing …


Systematic Evaluation Of A Variable Speed Limit System In St. Louis Missouri, Khushboo Lall, Ghulam H. Bham May 2011

Systematic Evaluation Of A Variable Speed Limit System In St. Louis Missouri, Khushboo Lall, Ghulam H. Bham

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper presents the systematic evaluation of Variable Speed Limit (VSL) system implemented on I-270 in St. Louis County. the system varies the speed limit in real time during periods of recurring and non-recurring congestion to prevent traffic from breaking down. the system was evaluated objectively and subjectively, and this paper describes the objective evaluation of the system. the objective evaluation was performed by comparing the traffic flow parameters during static speed limit (pre-VSL) with variable speed limit (post-VSL) by using five measures of performance: 1) speed, 2) volume, 3) occupancy, 4) travel time, and 5) congestion measures. Identification of …


An Exploratory Study Of Speed Limit Compliance In Missouri Work Zones, Mojtaba A. Mohammadi, Ghulam Bham, Hadi Khazraee May 2011

An Exploratory Study Of Speed Limit Compliance In Missouri Work Zones, Mojtaba A. Mohammadi, Ghulam Bham, Hadi Khazraee

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study evaluated the speed compliance with the posted speed limit both quantitatively and qualitatively using objective and subjective data analysis. Free flow speed data for three work zones on I-44 in Missouri were used for the objective evaluation. Speeds analyzed for cars and trucks were distributed normally. Construction activity had a significant effect in reducing the speed of vehicles. Results indicate that the speeds of vehicles were statistically higher than the speed limit regardless of the construction activity, when the lane width was not reduced. the subjective evaluation investigated the drivers' perception of driving through the work zone by …


Travel Time Reliability Estimation: Use Of Median Travel Time As Measure Of Central Tendency, M. Arezoumandi, Ghulam H. Bham May 2011

Travel Time Reliability Estimation: Use Of Median Travel Time As Measure Of Central Tendency, M. Arezoumandi, Ghulam H. Bham

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper proposes use of median travel time compared to mean travel time as the measure of central tendency to calculate Buffer Time Index (BTI), one of the most important measures of travel time reliability. This study examined gamma, exponential, largest extreme value, smallest extreme value, logistic, Weibull, lognormal and log-logistic distributions to determine the best fit to travel time data for two cases: 24 hours and peak hours for a highway with Variable Speed Limit (VSL) conditions. the goodness-of-fit tests indicated that the log-normal distribution best represented the travel time data for peak periods and log-logistic distribution better fitted …


Slip Ramp Spacing Design For Truck Only Lanes Using Microscopic Simulation, Ghulam H. Bham, Manoj Vallati May 2011

Slip Ramp Spacing Design For Truck Only Lanes Using Microscopic Simulation, Ghulam H. Bham, Manoj Vallati

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

For the Corridors of the Future project, slip ramps will provide access to trucks between the proposed truck-only lanes (TOLs) and general-purpose lanes (GPLs) for trucks to exit using at-grade interchanges. This paper proposes recommendations for slip ramp spacing between the TOLs and the general GPLs along Missouri rural interstate highways using a microscopic simulation model, VISSIM. Simulation of peak period traffic conditions indicated that heavy vehicle speeds were directly proportional to the lengths of the merge, diverge, and link sections. the proposed design recommendations for slip ramp spacing are based on the results of these section lengths. Central composite …


Wave Passage And Ground Motion Incoherency Effects On Seismic Response Of An Extended Bridge, Aman M. Mwafy, Oh Sung Kwon, Amr Elnashai, Youssef M.A. Hashash May 2011

Wave Passage And Ground Motion Incoherency Effects On Seismic Response Of An Extended Bridge, Aman M. Mwafy, Oh Sung Kwon, Amr Elnashai, Youssef M.A. Hashash

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper investigates the implications of ground motion spatial variability on the seismic response of an extended highway bridge. an existing 59-span, 2,164-meter bridge with several bearing types and irregularity features was selected as a reference structure. the bridge is located in the New Madrid Seismic Zone and supported on thick layers of soil deposits. Site-specific bedrock input ground motions were selected based on a refined probabilistic seismic hazard analysis of the bridge site. Wave passage and ground motion incoherency effects were accounted for after propagating the bedrock records to the ground surface. the results obtained from inelastic response-history analyses …