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2012

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Articles 751 - 780 of 1093

Full-Text Articles in Civil and Environmental Engineering

Monitoring The Effects Of Knickpoint Erosion On Bridge Pier And Abutment Structural Damage Due To Scour, Thanos Papanicolaou, David M. Admiraal, Christopher Wilson, Clark W. Kephart Jan 2012

Monitoring The Effects Of Knickpoint Erosion On Bridge Pier And Abutment Structural Damage Due To Scour, Thanos Papanicolaou, David M. Admiraal, Christopher Wilson, Clark W. Kephart

Mid-America Transportation Center: Final Reports and Technical Briefs

The goal of this study was to conduct a field-oriented evaluation, coupled with advanced laboratory techniques, of channel degradation in a stream of the Deep Loess Region of western Iowa, namely, Mud Creek. The Midwestern United States is an ideal place for such a study, considering that approximately $1 billion of infrastructure and farmland has been lost recently to channel degradation. A common form of channel degradation in this region is associated with the formation of knickpoints, which naturally manifest as short waterfalls within the channel that migrate upstream. As flow plunges over a knickpoint face, scouring of the downstream …

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Development Of A Methodology For Assessment Of Crash Costs At Highway- Rail Grade Crossings In Nebraska, Aemal Khattak, Eric Thompson Jan 2012

Development Of A Methodology For Assessment Of Crash Costs At Highway- Rail Grade Crossings In Nebraska, Aemal Khattak, Eric Thompson

Mid-America Transportation Center: Final Reports and Technical Briefs

An accurate measure of crash costs is required to support effective decision-making about transportation investments. In particular, underinvestment will occur if measurement fails to capture the full cost of crashes. Such mis-measurement and underinvestment may be occurring in the case of crashes at highway-rail grade crossings (HRGCs). HRGC crash costs can be substantial because of the severity of crashes. However, another important potential cost is the disruption to the transportation and logistics system. Existing methodologies capture the first set of costs but often fail to fully capture the second set. This research provides a standardized methodology for assessing the expected …

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Safety Improvements At Highway-Railroad Crossing For Pedestrians And Bicyclists And The Assessment Of Long- Term Effects Of Centerline Curbing, Aemal Khattak, Zheng Luo Jan 2012

Safety Improvements At Highway-Railroad Crossing For Pedestrians And Bicyclists And The Assessment Of Long- Term Effects Of Centerline Curbing, Aemal Khattak, Zheng Luo

Mid-America Transportation Center: Final Reports and Technical Briefs

The focus of the research reported herein was on assessing the long-term effectiveness of median barriers at highway-rail grade crossings (HRGCs), the impacts of barrier maintenance in resurrecting safety, and on exploring and assessing ways to improve pedestrian and bicyclist safety at HRGCs. Nebraska has about 7,000 HRGCs and each one represents a potential conflict point among trains and highway users, i.e., motorists, pedestrians, and bicyclists. Safety at HRGCs is compromised when highway users resort to unsafe maneuvers, such as passing around closed gates when trains are approaching. Gate-related violations by motorists, pedestrians, and bicyclists were studied at three selected …

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Implementation Of Warm-Mix Asphalt Mixtures In Nebraska Pavements, Yong-Rak Kim, Jun Zhang, Hoki Ban Jan 2012

Implementation Of Warm-Mix Asphalt Mixtures In Nebraska Pavements, Yong-Rak Kim, Jun Zhang, Hoki Ban

Mid-America Transportation Center: Final Reports and Technical Briefs

The primary objective of this research is to evaluate the feasibility of several WMA mixtures as potential asphalt paving mixtures for Nebraska pavements. To that end, three well-known WMA additives (i.e., Sasobit, Evotherm, and Advera synthetic zeolite) were evaluated. For a more realistic evaluation of the WMA approaches, trial pavement sections of the WMA mixtures and their HMA counterparts were implemented in Antelope County, Nebraska. More than one ton of field-mixed loose mixtures was collected at the time of paving and was transported to the NDOR and UNL laboratories to conduct comprehensive laboratory evaluations and pavement performance predictions of the …

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Speed Limit Recommendation In Vicinity Of Signalized, High-Speed Intersection, Anuj Sharma Ph.D., Laurence Rilett Ph.D., Zifeng Wu M.S., Shefang Wang Jan 2012

Speed Limit Recommendation In Vicinity Of Signalized, High-Speed Intersection, Anuj Sharma Ph.D., Laurence Rilett Ph.D., Zifeng Wu M.S., Shefang Wang

Mid-America Transportation Center: Final Reports and Technical Briefs

This report presents the results of Nebraska Department of Roads (NDOR) research project SPR-P1 (11) M307, which evaluated the traffic operations and safety effects of 5 mph and 10 mph speed limit reductions in the vicinity of high-speed, signalized intersections with advance warning flashers (AWF). The methodology involved two studies: 1) field study of the impact of speed limit reduction at seven high-speed intersections, 2) crash analysis using the 10-year history from 28 high-speed intersections. In the field study, traffic operational effects of the reduced speed limits were analyzed for seven high-speed, signalized intersections with AWF, using the Quantile regression …

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Assessing The Structural, Driver And Economic Impacts Of Traffic Pole Mounted Wind Power Generator And Solar Panel Hybrid System, Anuj Sharma Ph.D., Justice Appiah Ph.D., Scott K. Rosenbaugh Jan 2012

Assessing The Structural, Driver And Economic Impacts Of Traffic Pole Mounted Wind Power Generator And Solar Panel Hybrid System, Anuj Sharma Ph.D., Justice Appiah Ph.D., Scott K. Rosenbaugh

Mid-America Transportation Center: Final Reports and Technical Briefs

This project evaluates the physical and economic feasibility of using existing traffic infrastructure to mount wind power generators. Some possible places to mount a light weight wind generator and solar panel hybrid system are: i) Traffic signal pole and ii) Street Light pole. Traffic signal poles can themselves have multiple designs depending on type of mount (mast arm vs. span wire) and the width of the intersection (load carried) etc. The close proximity of street light poles and traffic signal poles to the traffic cabinets, which can be used for storing the battery banks, make them good candidates to mount …

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Concrete Surface With Nano-Particle Additives For Improved Wearing Resistance To Increasing Truck Traffic, Genda Chen, Dongming Yan Ph.D., Chenglin Wu Ph.D., Nicholas Leventis Ph.D, Shruti Mahadik Ph.D., Zhibin Lin Ph.D Jan 2012

Concrete Surface With Nano-Particle Additives For Improved Wearing Resistance To Increasing Truck Traffic, Genda Chen, Dongming Yan Ph.D., Chenglin Wu Ph.D., Nicholas Leventis Ph.D, Shruti Mahadik Ph.D., Zhibin Lin Ph.D

Mid-America Transportation Center: Final Reports and Technical Briefs

This study focused on the use of nanotechnology in concrete to improve the wearing resistance of concrete. The nano materials used were polymer cross-linked aerogels, carbon nanotubes, and nano-SiO2, nano-CaCO3, and nano-Al2O3 particles. As an indirect measurement of the concrete wearing resistance, the tensile and compressive properties and the permeability of concrete were evaluated for various mix designs. The optimal amount of nano material additives were determined following the American Society of Testing Methods (ASTM) standard test methodologies. The test results from the materials were compared for their mechanical behaviors. This type of technology may potentially improve the comfort level …

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Pilot Study On Rugged Fiber Optic Brillouin Sensors For Large-Strain Measurements To Ensure The Safety Of Transportation Structures, Genda Chen, Zhi Zhou, Hai Xiao, Ying Huang Jan 2012

Pilot Study On Rugged Fiber Optic Brillouin Sensors For Large-Strain Measurements To Ensure The Safety Of Transportation Structures, Genda Chen, Zhi Zhou, Hai Xiao, Ying Huang

Mid-America Transportation Center: Final Reports and Technical Briefs

Brillouin-scattering Optical Time Domain Reflectometry (BOTDR) is a viable technology for simultaneous, distributed strain and temperature measurements for miles-long transportation structures. It is a promising tool to ensure the smooth operation and safety of bridge structures that are key links in surface transportation networks or between various transportation modes: i.e., from airport to train station. Currently, telecom-grade optical fibers are widely used in civil engineering for strain and temperature measurements. These fibers are very fragile and easy to break during installation and measurement. In order to understand the ultimate behavior of structures, more rugged optical fibers such as carbon/polyimide coated …

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Use Of Fiber Bragg Grating (Fbg) Sensors For Performing Automated Bridge Pier Structural Damage Detection And Scour Monitoring, A.N. Thanos Papnicolaou Ph.D., Achilleas Tsakiris Jan 2012

Use Of Fiber Bragg Grating (Fbg) Sensors For Performing Automated Bridge Pier Structural Damage Detection And Scour Monitoring, A.N. Thanos Papnicolaou Ph.D., Achilleas Tsakiris

Mid-America Transportation Center: Final Reports and Technical Briefs

The goal of this study was to evaluate the performance of Fiber Bragg Grating (FBG) sensors able to detect impacts with different frequencies on a bridge pier. The FBG technology was evaluated under controlled conditions in a laboratory flume set-up to mimic the flow, sediment, and design characteristics of a pier structure. The system was calibrated using site-specific properties to relate strain to a known magnitude force for different bridge pier designs, different scour depths, and structural impacts. The FBGs proved a reliable measure of strain and displacement for key components of bridge structures, such as piers, during varying flow …

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Improving Freight Fire Safety: Experiment Testing And Computer Modeling To Further Development Of Mist-Controlling Additives For Fire Mitigation, Albert Ratner Ph.D., University Of Iowa Jan 2012

Improving Freight Fire Safety: Experiment Testing And Computer Modeling To Further Development Of Mist-Controlling Additives For Fire Mitigation, Albert Ratner Ph.D., University Of Iowa

Mid-America Transportation Center: Final Reports and Technical Briefs

With the purpose to minimize or prevent crash-induced fires in road and rail transportation, the current interest in bio-derived and blended transportation fuels is increasing. Based on two years of preliminary testing and analysis, it appears to be clear that polymeric additives may be added to diesel fuel to mitigate the formation of fine mists while allow regular flow through the fuel system. In this work, computer modeling was adapted as a fast and cost-effective methodology to identify the target range where polymeric additives could impact the shear-thickening effect on fuels. The Volume of Fraction (VOF) method was used within …

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Transportation Impacts Of The Chicago River Closure To Prevent An Asian Carp Infestation, Aaron Strong Ph.D., Nikhil Sikka Ph.D., Lindsay Salvatore Ph.D. Jan 2012

Transportation Impacts Of The Chicago River Closure To Prevent An Asian Carp Infestation, Aaron Strong Ph.D., Nikhil Sikka Ph.D., Lindsay Salvatore Ph.D.

Mid-America Transportation Center: Final Reports and Technical Briefs

This project develops a simple linear programming model of the Upper Midwest regions rail transportation network to test whether a closure of the Chicago River to freight traffic would impact the capacity constraint of the rail system. The result suggest that the rail network in the Upper Midwest regions are nowhere near approaching capacity and that a closure would have little impact on the rail network. Two noteworthy sets of commodities may be adversely affected, cereal grains and other agricultural product and gravel and crushed stone.

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An Improved Prediction Model For Spacecraft Damage Following Orbital Debris Impact, Joel E. Williamsen, William P. Schonberg Jan 2012

An Improved Prediction Model For Spacecraft Damage Following Orbital Debris Impact, Joel E. Williamsen, William P. Schonberg

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper offers a new set of 'generic', data-Based hole size and crank length prediction models for spherical orbital debris particles impacting multi-plate targets at velocities up to ~12 km/s. the equations are applicable to a wide variety of spacecraft target configurations, but are limited to hole sizes above, but relatively near, the ballistic limit of the impacting particles. Additional work is underway to expand these models to diameters farther above the ballistic limit for the described shield types.

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Breaking Internal Waves On A Shelf Slope Using Numerical Simulations, Subhas K. Venayagamoorthy, Oliver B. Fringer Jan 2012

Breaking Internal Waves On A Shelf Slope Using Numerical Simulations, Subhas K. Venayagamoorthy, Oliver B. Fringer

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The subject of internal waves interacting with bottom topographic features in the ocean has received much attention in the past few decades. This heightened interest is mainly due to a conjecture that breaking internal waves at boundaries can be a significant source of turbulence, leading to mixing and transport in the ocean. In this paper, we present results from high-resolution three-dimensional numerical simulations of an internal wave interacting with a shelf break in a linearly stratified fluid in order to highlight the instabilities that contribute to wave breaking over topography. The results show the development of a nonlinear internal bolus …

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Performance Evaluation And Finite Element Analysis Of Fiber Reinforced Precast Concrete Underground Structures, Ashley Wilson Jan 2012

Performance Evaluation And Finite Element Analysis Of Fiber Reinforced Precast Concrete Underground Structures, Ashley Wilson

Civil Engineering Theses - Archive

This study aimed at evaluating the performance of BASF Synthetic and Steel fibers as alternative reinforcements in concrete pipes. A total of 93 synthetic fiber and 60 steel fiber reinforced pipes were produced and tested based on the ASTM C497 in order to have a benchmark for comparison with conventionally reinforced concrete pipes. Three production sites with different production equipment were used in different geographical locations in the United States. Standard ASTM C76 diameters of up to 36 in. with "Wall-B" and "Wall-C" were used in this study for both synthetic and steel fibers. Vertical and horizontal load-deformation plots for …

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Engineering Behavior Of Lime Treated High Sulfate Soils, Ahmed Hassan Mohamed Gaily Jan 2012

Engineering Behavior Of Lime Treated High Sulfate Soils, Ahmed Hassan Mohamed Gaily

Civil Engineering Theses - Archive

Regardless of increased knowledge and awareness of sulfate heave, the Texas Department of Transportation (TxDOT) continues to experience pavement failures during and immediately after construction on transportation infrastructures intended to last at least 20 years. Failures are predominantly observed in sites where high sulfate soils of 8,000 ppm or higher levels. Many of these failures are attributed to sulfate-induced heave where an expansive mineral called Ettringite is formed from calcium-based stabilizers (lime or cement) reacting with water, clay, and sulfates. The reactions responsible for Ettringite formation are extremely complex which make generalizations concerning the rate and magnitude of heaving in …

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Comparative Application Of Two Nanoparticles In Cement Mortar, Vinoth Mohanam Jan 2012

Comparative Application Of Two Nanoparticles In Cement Mortar, Vinoth Mohanam

Civil Engineering Theses - Archive

Carbon Nanotubes (CNTs) and Carbon Nanofibers (CNFs) are two of the most promising advanced materials in the construction industry due to their excellent material properties. In this study, their application in cement mortar is studied comparatively as possible choice for concrete repair. CNT and CNF have very high aspect ratio due to which the Van der Wal forces between the CNT and CNF tend to agglomerate; thus forming bundles. In order to achieve proper dispersion, ultrasonic energy was used to disperse the CNT and CNF in the aqueous solution. The mechanical properties such as compressive strength and flexural strength of …

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The Effects Of Climate, Soil, And Vegetation On The Design Of Water Balance Covers For Solid Waste Landfills In Texas, Salman Baig Jan 2012

The Effects Of Climate, Soil, And Vegetation On The Design Of Water Balance Covers For Solid Waste Landfills In Texas, Salman Baig

Civil Engineering Theses - Archive

The purpose of this study is to determine the effects of climate, soil, and vegetation on the design of water balance (WB) covers for solid waste landfills in Texas. This study was conducted using water balance software (UNSAT-H model) that considers unsaturated soil hydraulics and plant water uptake. To date, limited research has been conducted for WB covers in Texas. Texas is located in the central region of the United States and encounters approximately nine distinct 5 inch precipitation increments or ranges, unlike any other state in the United States. Texas includes various climate regions and is a favorable choice …

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Effect Of Saline Water On Landfill Gas Generation Of Municipal Solid Waste, Yogavathani Sivanesan Jan 2012

Effect Of Saline Water On Landfill Gas Generation Of Municipal Solid Waste, Yogavathani Sivanesan

Civil Engineering Theses - Archive

The Enhanced Leachate Recirculation (ELR) landfills operation results in rapid waste stabilization, waste decomposition and increased rate of gas generation. However, operating landfill as an ELR landfill requires availability of sufficient amount of fresh water in close proximity to the landfill facility. In coastal regions, where fresh water supplies may be scarce, available saline water may be considered for ELR operation. However, the effects of saline water on the decomposition solid waste and landfill gas generation are unknown and need to be investigated., The objectives of the current research are to investigate the effects of adding and/or recirculating saline water …

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Identifying Issues Impacting Productivity Of Box Jacking Projects, Bhaumi Bhavan Chaurasia Jan 2012

Identifying Issues Impacting Productivity Of Box Jacking Projects, Bhaumi Bhavan Chaurasia

Civil Engineering Theses - Archive

Jacking is a trenchless construction technique used for installing underground pipeline system. Jacking method is more widely used for upgrading under capacity culverts and drainage structures under roads and railroad tracks. Also, this method is used for installing underground pipelines such as watermains, sewers etc.in populated and developed urban areas. In this method, culverts (segments) are installed through the ground from an entry shaft to an exit shaft. During the excavation and spoil removal processes, workers are required to be inside the pipe, this is essentially what separates pipe jacking trenchless construction method from microtunneling technology. The minimum recommended diameter …

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Effect Of Nano Zero Valent Iron On Degradation Of Municipal Solid Waste In Bioreactor Landfills, Meenakshi Gangopadhyay Jan 2012

Effect Of Nano Zero Valent Iron On Degradation Of Municipal Solid Waste In Bioreactor Landfills, Meenakshi Gangopadhyay

Civil Engineering Theses - Archive

Nanotechnology has substantial potential for reducing contamination, toxicity and overall human health hazards and environmental risks. In recent times, nano zero valent iron has proved to be effective in contaminant reduction and pollution control. Iron is an important micronutrient for the microbes involved in the anaerobic decomposition of solid waste in bioreactor landfills. Landfill leachate sometimes contains toxic compounds which nano zero valent iron has proven to be very effective in removing, particularly chlorinated organics, heavy metals, and odorous sulfides. Iron can also potentially increase landfill methane generation by removing long chain fatty acids and sulfides that inhibit methanogenesis.nZVI materials …

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An Investigation Of Pipe Jacking Loads In Trenchless Technology, Saeed Rahjoo Jan 2012

An Investigation Of Pipe Jacking Loads In Trenchless Technology, Saeed Rahjoo

Civil Engineering Theses - Archive

Pipe jacking is a trenchless technology method of installing pipes under existing facilities such as roads and railroads. Predicting jacking forces is important for planning, design, and construction phases of these projects. The jacking forces dictate shaft or pit locations, thrust block or backstop design, jacking equipment, use of intermediate jacking stations, and pipe bearing capacity. Calculating jacking forces depends on several site and project parameters such as soil and site conditions, lubrication, size of overcut, and steering corrections. Excessive jacking forces can damage the pipe and destabilize the drive shaft, which may stop project progress. There are different methods …

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Performance Of Large Diameter Polyvinyl Chloride (Pvc) Pipes In Water Applications, Pradip P. Deshmukh Jan 2012

Performance Of Large Diameter Polyvinyl Chloride (Pvc) Pipes In Water Applications, Pradip P. Deshmukh

Civil Engineering Theses - Archive

Polyvinyl chloride (PVC) pipes with diameters greater than 24" make up a small fraction of water utilities. Most of the research done on PVC pipes in water utilities focuses on diameters less than 24". Therefore, this thesis focuses on PVC water main pipelines with a diameter greater than 24" in an attempt to understand their performance in the water management facilities. This thesis had several objectives, such as to evaluate 24" and larger diameter PVC pipes in water transmission and distribution applications, calculate failure rate per hundred miles of PVC pipes at water utilities, categorize age of PVC pipelines with …

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Long-Term Performance Of Gfrp Reinforced Concrete Beams And Bars Subjected To Aggressive Environments, Yeonho Park Jan 2012

Long-Term Performance Of Gfrp Reinforced Concrete Beams And Bars Subjected To Aggressive Environments, Yeonho Park

Civil Engineering Dissertations - Archive

The use of fiber-reinforced polymer (FRP) bars in reinforced concrete (RC) structures has emerged as an alternative to traditional steel reinforcement environments and other applications where steel has shown greater vulnerability. Although the number of analytical and experimental studies on RC beams with FRP reinforcement has increased in recent decades, its long term performance is still questioned in comparison to the traditional steel reinforcement. That is, long-term performance is a much recognized but less-mentioned topic in the field of the reinforced concrete with glass-FRP (GFRP) re-bars. There is a need to validate long-term performance of FRP reinforced concrete structures, and …

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Dynamic Bus Lane, Isaac F. Joskowicz Jan 2012

Dynamic Bus Lane, Isaac F. Joskowicz

Civil Engineering Dissertations - Archive

This dissertation documents the research conducted to investigate the feasibility of implementing a "Dynamic Bus Lane" (DBL) system on Westheimer Road in Houston, Texas, and to determine the particular conditions when the system could be applied to other arterial streets. The DBL system is a bus preferential system which would turn a normal traffic lane into a bus lane when a bus is approaching a bus stop at a major intersection. The bus would activate a dynamic message sign that would change the lane use from a normal traffic lane to a bus lane for the time when the bus …

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Qualitative Evaluation Of Transportation Construction Related Social Costs And Their Impacts On The Local Community, Amanda Ferguson Jan 2012

Qualitative Evaluation Of Transportation Construction Related Social Costs And Their Impacts On The Local Community, Amanda Ferguson

Civil Engineering Theses - Archive

Although construction is valuable after completion, it can cause many disturbances throughout the duration of the project. These negative impacts, such as economic losses and annoyances, which face the community surrounding a construction project, are referred to as social costs. They are the inconveniences that confront the general public and take many forms such as traffic delays and congestion, decreased revenue, increased accidents, and air and noise pollution. Social costs negatively affect the surrounding environment and everyday quality of life. Social costs are often not incorporated into construction design, planning or budgets. This can be attributed to the complexity of …

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Development Of A Flexible Pavement Design Procedure Based On The Mechanistic - Empirical Pavement Design Guide: A Case Study, Ali Qays Abdullah Jan 2012

Development Of A Flexible Pavement Design Procedure Based On The Mechanistic - Empirical Pavement Design Guide: A Case Study, Ali Qays Abdullah

Civil Engineering Dissertations - Archive

This research developed design tables of new flexible pavement structures for New York State Department of Transportation based on the Mechanistic Empirical Design Guide (MEPDG). The design tables were developed using the MEPDG software for Regions 1, 3, and 7 for Upstate part of New York State and for Regions 8, 10, and 11 for the Downstate part of New York State. The MEPDG software was used to run design cases for combinations of: climate conditions, traffic volume, subgrade soil stiffness (Mr) and pavement structures. The conditions that the MEPDG was used to run were: the road structures classified as …

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Application Of Ellipse For Horizontal Alignment, Farzin Maniei Jan 2012

Application Of Ellipse For Horizontal Alignment, Farzin Maniei

Civil Engineering Theses - Archive

In highway design, horizontal alignments provide directional transition of roadways. Three categories of horizontal transition curves are simple circular curves, compound circular curves, and spiral circular curves. Compound and spiral curves, as alternatives to a simple circular curve, are often more costly since they are longer in length and require additional right-of-way. These costs differences are amplified at higher design speed. This study presents calculations associated with using a single elliptical arc in lieu of compound or spiral curves in situations where the use of simple circular curves is not prudent due to driver safety and comfort considerations. The study …

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Performance Comparison Of High Density Polyethylene Pipe, Chandan Venkatesh Jan 2012

Performance Comparison Of High Density Polyethylene Pipe, Chandan Venkatesh

Civil Engineering Theses - Archive

The current and forecasted major challenge faced by water utilities is delivering potable water efficiently with minimum loss to end users. Water pipe failure has negative impact not only local communities but also on the nation's economy. The American Water Works Association (AWWA) has estimated that it will cost over $250 billion to replace and renew the nation's water pipes over the next 20 years. According to the 2009 American Society of Civil Engineers (ASCE) Report Card, seven billion gallons of water are lost in this country every day!Every pipe has unique properties with advantages and limitations. During a pipe's …

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Effect Of Stress And Suction Histories Dynamic Properties Of Statically Compacted Silty Sand, William Allan Douglas Jan 2012

Effect Of Stress And Suction Histories Dynamic Properties Of Statically Compacted Silty Sand, William Allan Douglas

Civil Engineering Theses - Archive

This paper is devoted to the analysis of the experimental study whose intent is to find the effect of the stress/suction history on the dynamic properties of silty sand subjected to small- to mid-strains. The practical application of this study includes determining the effect on soil stiffness properties of increased soil suction (transpiration of water) followed by loading induced by shallow foundations and vice versa. Small-strain stiffness properties such as shear modulus, material damping, and shear wave velocity, are important subsoil parameters for proper analysis and design of unsaturated earth structures subject to static and dynamic loading. Traditional soil testing …

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An Evaluation Of Failure Modes For Cast Iron And Ductile Iron Water Pipes, Ameya Brahmanand Paradkar Jan 2012

An Evaluation Of Failure Modes For Cast Iron And Ductile Iron Water Pipes, Ameya Brahmanand Paradkar

Civil Engineering Theses - Archive

The need to evaluate the performance of cast iron and ductile iron water pipes is of great importance since they are the most common pipe materials for water mains. The concern in the water industry is about the cost involved in repairs and replacement of water pipes due to failure. The rate of pipe failures increases as the design life ends and become a financial burden on the water industry. This thesis evaluates the failure modes for the two most used pipe materials for water mains in the United States which are cast iron and ductile iron pipes. A study …

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