Civil and Environmental Engineering Commons^™

Low Viscosity Pore Fluid To Manufacture Transparent Soil, Honghua Zhao, Louis Ge, Ronaldo Luna

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Transparent soil has been investigated for its potential as a substitute research media for natural soil. the mechanism for manufacturing the transparent soil is through adding an appropriate pore fluid to silica gel particles with the same refractive index. Two types of high viscosity pore fluids were identified by Iskander in 1994. However, because of the high viscosity of these two pore fluids, air was easily entrapped, which made the manufacture of a large mass of transparent soil difficult. in addition, the identified pore fluids caused serious membrane deterioration during triaxial laboratory testing. This research presented herein is an experimental …

An Experimental Investigation Of Friction Bit Joining In Az31 Magnesium And Advanced High-Strength Automotive Sheet Steel, Rebecca Gardner

Theses and Dissertations

Friction Bit Joining (FBJ) is a recently developed spot joining technology capable of joining dissimilar metals. A consumable bit cuts through the upper layer of metal to be joined, then friction welds to the lower layer. The bit then snaps off, leaving a flange. This research focuses on FBJ using DP980 or DP590 steel as the lower layer, AZ31 magnesium alloy as the top layer, and 4140 or 4130 steel as the bit material. In order to determine optimal settings for the magnesium/steel joints, experimentation was performed using a purpose-built computer controlled welding machine, varying factors such as rotational speeds, …

Analyzing The Effectiveness Of Safety Measures Using Bayesian Methods, Daniel J. Thurgood

Theses and Dissertations

Recent research has shown that traditional safety evaluation methods have been inadequate in accurately determining the effectiveness of roadway safety measures. In recent years, advanced statistical methods have been utilized in traffic safety studies to more accurately determine the effectiveness of roadway safety measures. These methods, particularly hierarchical Bayesian statistical techniques, have the capabilities to account for the shortcomings of traditional methods. Hierarchical Bayesian modeling is a powerful tool for expressing rich statistical models that more fully reflect a given problem than a simpler model could. This paper uses a hierarchical Bayesian model to analyze the effectiveness of two types …

East Bay Energy Consortium Meeting Minutes, July 12, 2010, East Bay Energy Consortium

East Bay Energy Consortium Meeting Minutes

No abstract provided.

Improving Surveying Accuracy And Efficiency In Connecticut: An Accuracy Assessment Of Geoid03 And Geoid09, Thomas H. Meyer, Robert Baron

Department of Natural Resources and the Environment Articles

Comparing published NAVD 88 Helmert orthometric heights of First-Order bench marks against GPS-determined orthometric heights showed that GEOID03 and GEOID09 perform at their reported accuracy in Connecticut. GPS-determined orthometric heights were determined by subtracting geoid undulations from ellipsoid heights obtained from a network least-squares adjustment of GPS occupations in 2007 and 2008. A total of 73 markers were occupied in these stability classes: 25 class A, 11 class B, 12 class C, 2 class D bench marks, and 23 temporary marks with transferred elevations. Adjusted ellipsoid heights were compared against OPUS as a check. We found that: the GPS-determined orthometric …

An Examination Of Distributed Hydrologic Modeling Methods As Compared With Traditional Lumped Parameter Approaches, Murari Paudel

Theses and Dissertations

Empirically based lumped hydrologic models have an extensive track record of use where as physically based, multi-dimensional distributed models are evolving for various engineering applications. Despite the availability of high resolution data, better computational resources and robust numerical methods, the usage of distributed models is still limited. The purpose of this research is to establish the credibility and usability of distributed hydrologic modeling tools of the United States Army Corps of Engineers (USACE) in order to promote the extended use of distributed models. Two of the USACE models were used as the modeling tools for the study, with Gridded Surface …

Effect Of Relative Density And Stress Level On The Bearing Capacity Of Footings On Sand, D Loukidis, Rodrigo Salgado

Lyles School of Civil Engineering Faculty Publications

The design of shallow foundations relies on bearing capacity values calculated using empirical procedures that are based in part on solutions obtained using the method of characteristics, which assumes a soil that is perfectly plastic following an associated flow rule. In this paper the problem of strip and circular footings resting on the surface of a sand layer is analysed using the finite-element method. Analyses are performed using a two-surface plasticity constitutive model that realistically captures the aspects of the mechanical response of sands that are relevant to the bearing capacity problem. In particular, the model accounts for non-associated flow, …

Discussion Of "Potential Dangers Of Simplifying Combined Sewer Hydrologic/Hydraulic Models” By Joshua P. Cantone And Arthur R. Schmidt, Arturo S. León, Leonardo S. Nania, Venkataramana Sridhar

Civil Engineering Faculty Publications and Presentations

The authors of this paper provide a valuable discussion on the potential dangers of conduit skeletonization and subcatchment aggregation. For assessing these potential dangers, a "base model" (includes all sewers, nodes, inlets and gutters) and simplified models (successive removal of elements) of two catchments were used. The discussers congratulate the authors for their work on this relevant issue and for presenting their results in a clear and well organized way. The discussers however would like to raise some questions and comments regarding the results and their interpretation as presented in the paper.

Viscosity Effects In Vibratory Mobilization Of Residual Oil, Igor A. Beresnev, Wen Deng

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The last decade has seen clarifications of the underlying capillary physics behind stimulation of oil production by seismic waves and vibrations. Computational studies have prevailed, however, and no viscous hydrodynamic theory of the phenomenon has been proposed. For a body of oil entrapped in a pore channel, viscosity effects are naturally incorporated through a model of two-phase core-annular flow. These effects are significant at the postmobilization stage, when the resistance of capillary forces is overcome and viscosity becomes the only force resisting an oil ganglion's motion. A viscous equation of motion follows, and computational fluid dynamics (CFD) establishes the limits …

Assessment Of Climatic Vulnerability In The Upper Thames River Basin: Part 2, Leanna King, Tarana A. Solaiman, Slobodan P. Simonovic

Water Resources Research Report

Increasing greenhouse gas emissions will cause global temperature to rise in the coming years. Understanding the effects of rising temperature on the hydrologic cycle at a local scale is important in order to assess a wide scope of climate change impacts on management of water resources. Coupled Atmosphere-Ocean General Circulation Models (AOGCMs) are state-of-theart in climate change research, predicting the future climate based on plausible emission scenarios. Their spatial and temporal scales are quite large, so the results of their analyses must be brought to a local-scale through a downscaling process. There are several methods for downscaling AOGCM data; however …

Elimination Of Deck Joints Using A Corrosion Resistant Frp Approach, Ashok Reddy Aleti

Doctoral Dissertations

The research presented herein describes the development of durable link slabs for jointless bridge decks based on using FRP grid for reinforcement. Specifically, the ductility of the FRP material was utilized to accommodate bridge deck deformations imposed by girder deflection, temperature variations, and concrete shrinkage. It would also provide a solution to a number of deterioration problems associated with bridge deck joints.

The design concept of the link slabs was then examined to form the basis of design for FRP grid link slabs. Improved design of FRP grid link slab/concrete deck slab interface was confirmed in the numerical analysis. The …

Load Rating Of Complex Bridges, George Morcous, Kromel E. Hanna, Maher K. Tadros

Nebraska Department of Transportation: Research Reports

No abstract provided.

Mitigation Of Chloride And Sulfate Based Corrosion In Reinforced Concrete Via Electrokinetic Nanoparticle Treatment, Kunal Kupwade-Patil

Doctoral Dissertations

Concrete is a porous material which is susceptible to the migration of highly deleterious species such as chlorides and sulfates. Various external sources, including sea salt spray, direct seawater wetting, deicing salts and chlorides can contaminate reinforced concrete. Chlorides diffuse into the capillary pores of concrete and come into contact with the reinforcement. When chloride concentration at the reinforcement exceeds a threshold level it breaks down the passive oxide layer, leading to chloride induced corrosion. The application of electrokinetics using positively charged nanoparticles for corrosion protection in reinforced concrete structures is an emerging technology. This technique involves the principle of …

Failure Literacy In Structural Engineering, Norbert J. Delatte

Civil and Environmental Engineering Faculty Publications

The history of the development of practice in many engineering disciplines is, in large part, the story of failures, both imminent and actual, and of the changes to designs, standards and procedures made as the result of timely interventions or forensic analyses. All engineers, and more particularly structural engineers, should be failure literate. Failure literacy means knowing about the critical historical failure cases that have shaped the profession: not merely the surface technical details, but the environment, the communications difficulties and the procedural issues. In the US, an intensive effort has been under way for nearly a decade to promote …

A Life Cycle Cost Analysis Of Large-Scale Thermal Energy Storage Technologies For Buildings Using Combined Heat And Power, Kenneth Gaine, Aidan Duffy

Conference Papers

Buildings account for approximately 40% of energy consumption and greenhouse gas (GHG) emissions in developed economies, of which approximately 55% of building energy is used for heating and cooling. The reduction of building-related GHG emissions is a high international policy priority. For this reason and because there are many technical solutions for this, these polices should involve significant improvements in the uptake of small-scale energy efficient (EE) systems. However the widespread deployment of many technologies, must overcome a number of barriers, one of which is a temporal (diurnal or seasonal) mismatch between supply and demand. Costeffective thermal storage solutions have …

2010 Safety Belt Usage Survey In Kentucky, Kenneth R. Agent, Eric R. Green

Kentucky Transportation Center Research Report

The objective of this study was to establish 2010 safety belt and child safety seat usage rates in Kentucky. The 2010 survey continues to document the results after enactment of the original “secondary enforcement” statewide mandatory safety belt law in 1994 and the subsequent change to “primary enforcement” which was enacted in 2006. Data were collected at 160 randomly selected sites in 18 counties across Kentucky. Data from the individual sites were combined into a statewide percentage considering roadway functional classification, county, and vehicle miles traveled.

The data show that the usage rate in 2010 (80.3 percent) was almost identical …

Effects Of Chloride Contamination On Coatings Performance, Bobby W. Meade, Sudhir Palle, Theodore Hopwood Ii, Rick Younce

Kentucky Transportation Center Research Report

Research indicates that chloride concentration as determined by currently available field test methods does not reliably predict protective coating performance on KYTC bridges. Laboratory testing of chloride charged panels also failed to relate chloride concentration to coating performance. The coatings industry provides recommendations for acceptable chloride levels for various exposure conditions but bridges are different than other structural steel and the exposure conditions for bridges are not adequately addressed. Effective chloride remediation strategies and protective coatings that perform best in the presence of chlorides need to be identified.

Using Micro-Simulation To Evaluate Transit Signal Priority For Lrt Operations In A Downtown Environment, Faisal Mahmud

Civil & Environmental Engineering Theses & Dissertations

Transit Signal Priority or TSP is an operational strategy that facilitates the movement of transit vehicles such as buses, light rail or streetcars, through traffic-signal controlled intersections. The benefits of TSP operations include improved schedule adherence and improved transit travel times with minimal impact to normal traffic operations. New advances in Global Positioning Systems, detection and communication, and control strategies have helped overcome many problems with early systems and increased interest in implementing TSP for Light Rail Transit (LRT) and other transit operations. The increased capabilities of these advanced systems have led to a dramatic increase in operational and planned …

A Study Of Passive Earth Pressure In Anisotropic Sand With Various Wall Movement Modes, Achmad Bakri Muhiddin

Civil & Environmental Engineering Theses & Dissertations

This study investigated the effect of anisotropy on passive pressure in sands by developing computer simulation utilizing FLAC code for plane strain condition. A series of wall movement modes was applied namely translation, rotation about a point below the wall, RBT, and rotation about a point above the wall, RTT.

From comparisons with other FLAC model in translation mode with isotropic material, the coefficients of passive pressure K_p were similar to each other except for some combinations of zero dilation, low wall friction, and high angle of internal friction ϕ. Dilation angle has less effect on K_p than …

Design Aids Of Nu I-Grinder Bridges, Kromel Hanna, George Morcous, Maher K. Tadros

Nebraska Department of Transportation: Research Reports

No abstract provided.

Development Of A Temporary Concrete Barrier To Permanent Concrete Median Barrier Approach Transition, Mitchell J. Wiebelhaus, Karla A. Lechtenberg, Ronald K. Faller, John R. Rohde, Ryan J. Terpsma, Robert W. Bielenberg, Dean L. Sicking, John D. Reid

Nebraska Department of Transportation: Research Reports

No abstract provided.

Fatigue Strength Of Steel Bridge Members With Intersecting Welds, David T. Delong, Mark D. Bowman

JTRP Technical Reports

The brittle fracture of the Hoan Bridge in December 2000 highlighted the fracture susceptibility of details containing intersecting welds in steel bridges. Though it is now known that details with intersecting welds should be avoided, many existing bridges in Indiana contain details with intersecting welds. Little experimental data on the fatigue performance of these details exists.

The purpose of this study was to evaluate the fatigue strength of several details commonly found in steel bridges in Indiana that contain intersecting welds. Large-scale experimental fatigue testing were performed using nine steel beams to study the behavior of three basic types of …

Bs News July/August

Building Services Engineering

No abstract provided.

Snow And Ice Removal And Anti-Icing Synthesis Study, Bob Mccullouch

JTRP Technical Reports

No abstract provided.

Proposed Implementation Of The Indiana Erosion And Sediment Control Field Guide, Lynn A. Corson

JTRP Technical Reports

No abstract provided.

Synthesis Study: Development Of An Electronic Detection And Warning System To Prevent Overheight Vehicles From Impacting Overhead Bridges, Joseph V. Sinfield

JTRP Technical Reports

Overheight vehicle impacts with bridges are surprisingly common. The damage from collisions can range from minor to severe, and there is also evidence that some bridges are impacted multiple times, leading to the potential for cumulative damage effects. Thus there is a clear need to attempt to prevent overheight vehicle collisions with bridges.

This Synthesis Study provides a review of solutions that exist to detect and forewarn overheight vehicles and thereby prevent a collision, and specifically examines the breadth of available overheight vehicle detection technologies, the commercial availability of such equipment, and the experience of relevant DOTs with installed and …

Improving Robustness Of Hydrologic Parameter Estimation By The Use Of Moving Block Bootstrap Resampling, Hamid Moradkhani, Mohammad Ebtehaj, Hoshin V. Gupta

Civil and Environmental Engineering Faculty Publications and Presentations

Modeling of natural systems typically involves conceptualization and parameterization to simplify the representations of the underlying process. Objective methods for estimation of the model parameters then require optimization of a cost function, representing a measure of distance between the observations and the corresponding model predictions, typically by calibration in a static batch mode and/or via some dynamic recursive optimization approach. Recently, there has been a focus on the development of parameter estimation methods that appropriately account for different sources of uncertainty. In this context, we introduce an approach to sample the optimal parameter space that uses nonparametric block bootstrapping coupled …

The Utility Of Daily Large-Scale Climate Data In The Assessment Of Climate Change Impacts On Daily Streamflow In California, Edwin P. Maurer, H. G. Hidalgo, T. Das, M. D. Dettinger, D. R. Cayan

Civil, Environmental and Sustainable Engineering

Three statistical downscaling methods were applied to NCEP/NCAR reanalysis (used as a surrogate for the best possible general circulation model), and the downscaled meteorology was used to drive a hydrologic model over California. The historic record was divided into an “observed” period of 1950–1976 to provide the basis for downscaling, and a “projected” period of 1977–1999 for assessing skill. The downscaling methods included a biascorrection/ spatial downscaling method (BCSD), which relies solely on monthly large scale meteorology and resamples the historical record to obtain daily sequences, a constructed analogues approach (CA), which uses daily large-scale anomalies, and a hybrid method …

The Effect Of Service Installations On Structural Integrity Of Slabs In Buildings, Ladislaus Lwambuka

Tanzania Journal of Engineering and Technology (TJET)

In building construction industry service installations, usually housed in conduit pipes, are commonly mounted inside reinforced concrete structural elements. This practice is adopted to attain aesthetical outlook at both interior and exterior surfaces of the buildings. Depending on the extent of service installations, the cross sectional area of the load bearing structural member is substantially reduced. However, the current structural design guidelines have no provision to accommodate the extent to which the existence of conduit pipes impairs the load bearing capacity of the structural element though reduced cross sectional area. This study has attempted to address this gap in structural …

Best Practices For Dealing With Price Volatility In Utah's Residential Construction Market, James Packer Smith

Theses and Dissertations

Price volatility is a consistent problem that affects all of the parties involved in the residential construction industry. The myriad factors that can have an impact on construction costs are such that it is extremely hard to anticipate upcoming changes in a timely and accurate way. When prices fluctuate during the course of a project, estimates become erroneous and completion of projects within expected budgets becomes difficult. Increasing prices typically leave contractors with the majority of the risk burden due to the enforceability of contracts that are likely to have been executed months prior. The risk associated with the owner's …