Open Access. Powered by Scholars. Published by Universities.®
- Discipline
- Keyword
-
- Safety (6)
- Crash severity (4)
- Highway Safety (4)
- Bridge Infrastructure Safety (3)
- Pavement (3)
-
- Truck crashes (3)
- Work zones (3)
- Anxiety (2)
- Freight (2)
- Indirect tensile strength (2)
- Intermodal (2)
- MEPDG (2)
- MUTCD (2)
- Merge sign (2)
- Moisture susceptibility (2)
- Performance (2)
- Reliability index (2)
- Roadside Appurtenances (2)
- Scour (2)
- Stress (2)
- Stressors (2)
- Traffic (2)
- Transportation (2)
- Trucks (2)
- Vehicle (2)
- Warm mix asphalt (WMA) (2)
- Work zone (2)
- AASHTO LRFR (1)
- AASHTO Specification (1)
- Abutments (1)
Articles 91 - 120 of 141
Full-Text Articles in Civil Engineering
Direct Detection Of Localized Modulation Of On Concentration On An Electrode-Electrolyte Interface, Ravi Saraf, Gaurav Singh
Direct Detection Of Localized Modulation Of On Concentration On An Electrode-Electrolyte Interface, Ravi Saraf, Gaurav Singh
Mid-America Transportation Center: Final Reports and Technical Briefs
The present invention directly measures localized electrochemical processes on a planar electrode using differential interferometry. The ionic charge accumulation at the electrode-electrolyte interface may be directly measured by using differential interferometry as a function of magnitude and frequency (for example, 2-50 kHz) of an external potential applied on an electrode. Methods in accordance with the present invention probe the ion dynamics confined to the electrical double layer. An electric field is applied using a pure AC potential and a superposition of AC and DC-ramp potential to measure ion concentration and detect redox processes.
Computational Design Tool For Bridge Hydrodynamic Loading In Inundated Flows Of Midwest Rivers, Junke Guo, David M. Admiraal, Tian C. Zhang
Computational Design Tool For Bridge Hydrodynamic Loading In Inundated Flows Of Midwest Rivers, Junke Guo, David M. Admiraal, Tian C. Zhang
Mid-America Transportation Center: Final Reports and Technical Briefs
The hydraulic forces experienced by an inundated bridge deck have great importance in the design of bridges. The proper estimation of loading exerted by the flow on the structure is important for design plans and is pertinent for evaluating its vulnerability. During a flood or hurricane highway bridges over the sea or other waterways may become partially or completely submerged. Flood flows add significant hydrodynamic loading on bridges, possibly resulting in the shearing or overturning of the bridge deck and failure of the bridge superstructures. The overall objective of the study was to establish validated computational practice to address research …
Bottom Flange Reinforcement In Nu I-Girders, George Morcous Ph.D., Kromel Hanna Ph.D., Maher K. Tadros Ph.D., P.E.
Bottom Flange Reinforcement In Nu I-Girders, George Morcous Ph.D., Kromel Hanna Ph.D., Maher K. Tadros Ph.D., P.E.
Mid-America Transportation Center: Final Reports and Technical Briefs
The 1996 edition of AASHTO Standard Specifications for Highway Bridges stated that nominal confinement reinforcement be placed to enclose prestressing steel in the bottom flange of bridge girders from girder ends to at least a distance equal to the girder’s height. The 2004 edition of AASHTO LRFD Bridge Design Specifications changed the distance over which the confinement reinforcement was to be distributed from 1.0h to 1.5h, and gave minimum requirements for the amount of steel to be used, No.3 bars, and their maximum spacing, not to exceed 6.” Research was undertaken to study what impact, if any, confinement reinforcement had …
Load Rating Of Complex Bridges, George Morcous Ph.D., Kromel Hanna Ph.D., Maher K. Tadros Ph.D., P.E.
Load Rating Of Complex Bridges, George Morcous Ph.D., Kromel Hanna Ph.D., Maher K. Tadros Ph.D., P.E.
Mid-America Transportation Center: Final Reports and Technical Briefs
The National Bridge Inspection Standards require highway departments to inspect, evaluate, and determine load ratings for structures defined as bridges located on all public roads. Load rating of bridges is performed to determine the live load that structures can safely carry at a given structural condition. Bridges are rated for three types of loads, design loads, legal loads, and permit loads, which is a laborious and time-consuming task as it requires the analysis of the structure under different load patterns. Several tools are currently available to assist bridge engineers to perform bridge rating in a consistent and timely manner. However, …
Study Of Rf Propagation Characteristics For Wireless Sensor Networks In Railroad Environments, Hamid Sharif, Michael Hempel
Study Of Rf Propagation Characteristics For Wireless Sensor Networks In Railroad Environments, Hamid Sharif, Michael Hempel
Mid-America Transportation Center: Final Reports and Technical Briefs
The freight railroad industry in North America is exerting efforts to leverage Wireless Sensor Networks to monitor systems and components on railcars. This allows fault detection and accident prevention even while a train is moving. Railcars, constructed mostly of ferrous materials such as steel, are expected to severely impact signal propagation. To better understand this effect we first evaluated the signal characteristics when sensor nodes are placed in various locations around railcars. We used EM-Field modeling and evaluation techniques to obtain these results and found that node placement selection is critical for the node’s communication distance. As a second research …
Performance Measures Of Warm Asphalt Mixtures For Safe And Reliable Freight Transportation, Hosin "David" Lee Ph.D., P.E., Yongjoo "Thomas" Kim
Performance Measures Of Warm Asphalt Mixtures For Safe And Reliable Freight Transportation, Hosin "David" Lee Ph.D., P.E., Yongjoo "Thomas" Kim
Mid-America Transportation Center: Final Reports and Technical Briefs
Warm mix asphalt (WMA) is an emerging technology that can allow asphalt to flow at a lower temperature for mixing, placing and compaction. The advantages of WMA include reduced fuel consumption, less carbon dioxide emission, longer paving season, longer hauling distance, reduced oxidation of asphalt, early opening to traffic and a better working environment in the field. In the United States, WMA has become popular in recent years. However, to provide a safe and reliable highway for heavier truck traffic with a high tire pressure, WMA mixtures must meet requirements for strength, stiffness, rutting, and moisture resistance.
WMA mixtures with …
Extending Asphalt Pavement Life Using Thin Whitetopping, Mustaque Hossain, Sharmin Sultana
Extending Asphalt Pavement Life Using Thin Whitetopping, Mustaque Hossain, Sharmin Sultana
Mid-America Transportation Center: Final Reports and Technical Briefs
Due to budget constraints, many highway agencies are becoming interested in pavement preservation or rehabilitation rather than reconstruction to ensure pavement is in serviceable condition. Thin whitetopping (TWT) is the process of rehabilitating distressed asphalt concrete (AC) pavements by using a concrete overlay. This study was done to develop a design catalog for existing AC pavements to be overlaid with TWT. The finite element (FE) analysis was performed with SolidWorks, which is the 3-D FE software program used to develop this design catalog. The design considered different TWT thicknesses, existing AC layer thickness and modulus, the bonding condition between TWT …
Assessing The Damage Potential In Pretensioned Bridges, Caused By Increased Truck Loads Due To Freight Movements (Phase I), Robert J. Peterman, Steven Hammerschmidt
Assessing The Damage Potential In Pretensioned Bridges, Caused By Increased Truck Loads Due To Freight Movements (Phase I), Robert J. Peterman, Steven Hammerschmidt
Mid-America Transportation Center: Final Reports and Technical Briefs
When evaluating the condition of existing bridges determining in situ stresses in the members provides valuable information about the condition of the structures. In this study, a method of surface strain relief was investigated whereby the change in strain at the surface of concrete members is used to determine the in situ stress. The method involved mounting a linear electrical-resistance strain gage along the axis of maximum stress, coring around the gage, and then relating the change in strain to the corresponding stress in the member. Members were fabricated and varying stresses were applied in order to determine the accuracy …
Characteristics And Contributory Causes Related To Large Truck Crashes (Phase I) -Fatal Crashes, Sundanda Dissanayake Ph.D., P.E.
Characteristics And Contributory Causes Related To Large Truck Crashes (Phase I) -Fatal Crashes, Sundanda Dissanayake Ph.D., P.E.
Mid-America Transportation Center: Final Reports and Technical Briefs
One-ninth of all traffic fatalities in the United States have involved large trucks in the past five years, although large trucks contributed to only 3% of registered vehicles and 7% of vehicle miles travelled. This contrasting proportion indicates that truck crashes in general tend to be more severe than other crashes though they constitute a smaller sector of vehicles on the road. To study this issue, fatal crash data from the FARS was used to analyze characteristics and factors contributing to truck-involved crashes. Driver, vehicle, and crash-related contributory causes were identified, and as an extension the likelihood of occurrence of …
Improving Freight Fire Safety: Assessment Of The Effectiveness Of Mist-Controlling Additives In Mitigating Crash-Induced Diesel Fires, Albert Ratner Ph.D.
Improving Freight Fire Safety: Assessment Of The Effectiveness Of Mist-Controlling Additives In Mitigating Crash-Induced Diesel Fires, Albert Ratner Ph.D.
Mid-America Transportation Center: Final Reports and Technical Briefs
Adding long chained polymers to diesel has been proposed as a method to prevent crash fires by arresting the break-up of diesel fuel into a fine mist in transportation related accidents. The effect of such additives on the flow properties of diesel was investigated by studying the impact of poly-butadiene and diesel blend drops on a solid surface using high speed imaging. The addition of the polymer imparted shear-thinning behavior to diesel, and the base viscosities increased rapidly with polymer concentration. Four concentrations of the polymer were tested at three different impact speeds under atmospheric pressure. Maximum spread factors and …
Infrared Thermography-Driven Flaw Detection And Evaluation Of Hot Mix Asphalt Pavements, Yong K. Cho, Yong-Rak Kim Ph.D., Thaddaeus Bode
Infrared Thermography-Driven Flaw Detection And Evaluation Of Hot Mix Asphalt Pavements, Yong K. Cho, Yong-Rak Kim Ph.D., Thaddaeus Bode
Mid-America Transportation Center: Final Reports and Technical Briefs
This research was conducted to study more realistic explanations of how variables are created and dealt with during hot mix asphalt (HMA) paving construction. Several paving projects across the state of Nebraska have been visited where sensory devices were used to test how the selected variables contribute to temperature differentials including density, moisture content within the asphalt, material surface temperature, internal temperature, wind speed, haul time, and equipment type. Areas of high temperature differentials are identified using an infrared camera whose usefulness was initially confirmed with a penetrating thermometer. A non-nuclear density device was also used to record how the …
Investigating Rfid For Roadside Identification Involving Freight Commercial Vehicle Operators (Cvo), Erick C. Jones Ph.D., Judy Perkins Ph.D.
Investigating Rfid For Roadside Identification Involving Freight Commercial Vehicle Operators (Cvo), Erick C. Jones Ph.D., Judy Perkins Ph.D.
Mid-America Transportation Center: Final Reports and Technical Briefs
Radio Frequency Identification (RFID) is an emerging technology to track commercial vehicles. This transcript describes research that investigates the ability for RFID technologies to work in license plates. Mile markers are common fixtures on the roadside and may provide infrastructure to support identifying RFID to enabled Commercial Vehicle Operators (CVO). This research considers variables that affect the performance of a RFID License Plate System that uses a scanner located at the mile marker. Mile marker characteristics, such as horizontal distance and vertical height, were evaluated along with RFID tag characteristics, such tag type and license plate location.
Safety Investigation And Guidance For Work-Zone Devices In Freight Transportation Systems Subjected To Passenger Car And Truck Impacts With New Crash Standards, Ronald K. Faller Ph.D., P.E., Dean L. Sicking Ph.D., P.E., Karla A. Lechtenberg M.S.C.E., E.I.T., James C. Holloway M.S.C.E., E.I.T., Jennifer D. Schmidt
Safety Investigation And Guidance For Work-Zone Devices In Freight Transportation Systems Subjected To Passenger Car And Truck Impacts With New Crash Standards, Ronald K. Faller Ph.D., P.E., Dean L. Sicking Ph.D., P.E., Karla A. Lechtenberg M.S.C.E., E.I.T., James C. Holloway M.S.C.E., E.I.T., Jennifer D. Schmidt
Mid-America Transportation Center: Final Reports and Technical Briefs
Crashworthy, work-zone, portable sign support systems accepted under NCHRP Report No. 350 were analyzed to predict their safety peformance according to the TL-3 MASH evaluation criteria. An analysis was conducted to determine which hardware parameters of sign support systems would likely contribute to the safety performance with MASH. The acuracy of the method was evaluated through full-scale crash testing. Four full-scale crash tests were conducted with a pickup truck. Two tall-mounted, sign support systems with aluminum sign panels failed the MASH criteria due to windshield penetration. One low-mounted system with a vinyl, roll-up sign panel failed the MASH criteria due …
Impact Of Truck Loading On Design And Analysis Of Asphaltic Pavement Structures, Yong-Rak Kim, Hokie Ban, Soohyok Im
Impact Of Truck Loading On Design And Analysis Of Asphaltic Pavement Structures, Yong-Rak Kim, Hokie Ban, Soohyok Im
Mid-America Transportation Center: Final Reports and Technical Briefs
Mechanistic-Empirical Pavement Design Guide (MEPDG) is an improved methodology for pavement design and the evaluation of paving materials. However, in spite of significant advancements to pre-existing traditional design methods, the MEPDG is known to be limited in its accurate prediction of mechanical responses and damage in asphaltic pavements. This restriction is both due to the use of simplified structural analysis methods, and a general lack of understanding of the fundamental constitutive behavior and damage mechanisms in paving materials. This is additionally affected by the use of circular tire loading configurations. Performance prediction and pavement life are determined based on the …
Layer Moduli Of Nebraska Pavements For The New Mechanistic-Empirical Pavement Design Guide (Mepdg), Yong-Rak Kim, Soohyok Im, Hoki Ban
Layer Moduli Of Nebraska Pavements For The New Mechanistic-Empirical Pavement Design Guide (Mepdg), Yong-Rak Kim, Soohyok Im, Hoki Ban
Mid-America Transportation Center: Final Reports and Technical Briefs
As a step-wise implementation effort of the Mechanistic-Empirical Pavement Design Guide (MEPDG) for the design and analysis of Nebraska flexible pavement systems, this research developed a database of layer moduli — dynamic modulus, creep compliance, and resilient modulus — of various pavement materials used in Nebraska. The database includes all three design input levels. Direct laboratory tests of the representative Nebraska pavement materials were conducted for Level 1 design inputs, and surrogate methods, such as the use of Witczak’s predictive equations and the use of default resilient moduli based on soil classification data, were evaluated to include Level 2 and/or …
Foundation Design For High Tension Cable Guardrails, John R. Rohde Ph.D., P.E., Ling Zhu Ph.D., Ryan J. Terpsma B.S.M.E
Foundation Design For High Tension Cable Guardrails, John R. Rohde Ph.D., P.E., Ling Zhu Ph.D., Ryan J. Terpsma B.S.M.E
Mid-America Transportation Center: Final Reports and Technical Briefs
High tension cable guardrail is becoming increasing popular in median and roadside applications due to the promise of reduced deflections upon impact and reduced maintenance. As the performance of these systems is observed in service, there is a growing concern over the end anchorage foundation performance of current systems. Foundations for high tension systems must not only be capable of restraining the impact load of a vehicle but must also restrain the initial pretension on the cable system as well as temperature induced loads. While it may be acceptable for many roadside safety devices to require foundation repair after impact, …
Estimating Highway Pavement Damage Costs Attributed To Truck Traffic, Yong Bai, Steven D. Schrock, Thomas E. Mulinazzi, Wenhua Hou, Chunxiao Liu, Umar Firman
Estimating Highway Pavement Damage Costs Attributed To Truck Traffic, Yong Bai, Steven D. Schrock, Thomas E. Mulinazzi, Wenhua Hou, Chunxiao Liu, Umar Firman
Mid-America Transportation Center: Final Reports and Technical Briefs
Kansas is one of the leaders in meat production in the United States. In the southwest Kansas region, there are more than three hundred feed yards and several of the biggest meat processing plants in the nation. Heavy trucks (e.g., tractor-trailers) have been used primarily for transporting processed meat, meat byproducts, grain, and other related products. With the continuous growth of these industries, there will be more trucks on highways transporting meat and meat-related products in southwest Kansas. These trucks cause noteworthy damage to Kansas highway pavements, which in turn leads to more frequent maintenance actions and ultimately more traffic …
Extending Pavement Life Using Thin Surfacing To Counter The Effect Of Increased Truck Traffic Due To Freight Movements On Highways, Mustaque Hossain Ph.D., P.E., Vikranth S. Manepalli, Shaidur Rahman, Haritha Y. Musty
Extending Pavement Life Using Thin Surfacing To Counter The Effect Of Increased Truck Traffic Due To Freight Movements On Highways, Mustaque Hossain Ph.D., P.E., Vikranth S. Manepalli, Shaidur Rahman, Haritha Y. Musty
Mid-America Transportation Center: Final Reports and Technical Briefs
The highways in the Midwest are experiencing a considerable amount of truck traffic due to increased freight transportation. There is clearly a risk to the highway infrastructure caused by this additional truck traffic that will also have an increasingly detrimental effect on the safety of the citizens, the traveling public in terms of congestion, and the economy of the entire region. Traditionally the life of the pavements has been extended by a variety of rehabilitation techniques. For example, techniques used by the Kansas Department of Transportation (KDOT) include route and crack seal, chip seal, 1- to 4-inch overlay, 1- to …
Automated Erosion System To Protect Highway Bridge Crossings At Abutments, Thanos Papanicolaou Ph.D., Christopher Wilson Ph.D., Mohamed Elkakeem Ph.D.
Automated Erosion System To Protect Highway Bridge Crossings At Abutments, Thanos Papanicolaou Ph.D., Christopher Wilson Ph.D., Mohamed Elkakeem Ph.D.
Mid-America Transportation Center: Final Reports and Technical Briefs
A new instrument (Photo-Electronic Erosion Pin, or PEEP) was examined in collecting field data and remotely monitoring bank erosion near bridge abutments during floods. The performance of PEEPs was evaluated through a detailed field study to determine factors affecting their records. Proper calibration of the instrument was important in obtaining accurate erosion lengths. Calibration of the PEEPs within the banks nearby the study reach provided the most accurate erosion lengths. In addition, comparison with traditional, manual methods was recommended. Bank erosion was monitored at two study sites at the Clear Creek Watershed (CCW), IA between May 2009 and December 2009 …
Closed Course Testing Of Portable Rumble Strips To Improve Truck Safety At Work Zones, Steven D. Schrock, Yong Bai
Closed Course Testing Of Portable Rumble Strips To Improve Truck Safety At Work Zones, Steven D. Schrock, Yong Bai
Mid-America Transportation Center: Final Reports and Technical Briefs
The purpose of this research was to compare the attention-getting characteristics, movements and vertical displacements of several portable, reusable rumble strips. The attention-getting characteristics and displacement were measured after passes of a fully loaded heavy truck and a passenger vehicle. Sound and vibration tests revealed that the portable plastic rumble strips were more effective on cars than trucks for generating in-vehicle vibration and increasing in-vehicle sound levels. Further, they were generally better able to match the characteristics of the tested permanent rumble strip compared to the adhesive rumble strips, and that this was also true for the configurations that contained …
Risk Mitigation For Highway And Railway Bridges, Andrzej S. Nowak, Marek Kozikowski,, Marta Lutomirska,
Risk Mitigation For Highway And Railway Bridges, Andrzej S. Nowak, Marek Kozikowski,, Marta Lutomirska,
Mid-America Transportation Center: Final Reports and Technical Briefs
Performance of the transportation network strongly depends on the performance of bridges. Bridges constitute a vital part of the transportation infrastructure system and they are vulnerable to extreme events such as natural disasters (i.e., hurricanes, earthquakes, floods, major storms), as well as hazards stemming from negligence and improper maintenance, collisions (vessels and vehicles), intentional acts of vandalism, and terrorist attacks. These structures must be protected but the current approach to risk is not rational. Therefore, the objective of this project is to develop efficient risk analysis procedures for assessment of the actual safety reserve in highway and railway bridges. The …
Computer Aided Modeling Of Soil Mix Designs To Predict Characteristics And Properties Of Stabilized Road Bases, Charles W. Berryman Ph.D., Cpc, Wayne Jensen Ph.D., Tim Hensley P.E.
Computer Aided Modeling Of Soil Mix Designs To Predict Characteristics And Properties Of Stabilized Road Bases, Charles W. Berryman Ph.D., Cpc, Wayne Jensen Ph.D., Tim Hensley P.E.
Mid-America Transportation Center: Final Reports and Technical Briefs
Considerable data exists for soils that were tested and documented, both for native properties and properties with pozzolan stabilization. While the data exists there was no database for the Nebraska Department of Roads to retrieve this data for predicting soil properties. The conventional methods used to determine soil properties, such as maximum laboratory density and optimum moisture content, were tedious, labor intensive and time consuming. When soil stabilization is involved, more time and efforts are needed to determine maximum laboratory density, optimum moisture content and optimum pozzolan content. The objective of this project was to develop a computerized model to …
Inspector’S Manual For Mechanically Stabilized Earth Walls, Wayne Jensen Ph.D.
Inspector’S Manual For Mechanically Stabilized Earth Walls, Wayne Jensen Ph.D.
Mid-America Transportation Center: Final Reports and Technical Briefs
The scope of the project is to develop a condition rating system, creation of an inspector's manual to reference during inspection or address any training for inspectors at the district level. The research project will develop a MSE wall condition rating system and incorporate this system into the database being developed and create training and reference manuals
Investigation And Mitigation Of Driver Confusion At Modern Roundabouts, Aemal Khattak, Ram Bishu, Karen Schurr, Gregory Mcknight
Investigation And Mitigation Of Driver Confusion At Modern Roundabouts, Aemal Khattak, Ram Bishu, Karen Schurr, Gregory Mcknight
Mid-America Transportation Center: Final Reports and Technical Briefs
This research deals with two related issues: investigation and mitigation of roundabout elements that lead to driver confusion, and development of a flexible criteria matrix by which the Nebraska Department of Roads (NDOR) can evaluate arterial intersections to identify good candidates for conversion to roundabouts. The use of modern roundabouts along arterial roadways is relatively new in Nebraska. The first urban arterial roundabout was opened to traffic in June of 2002 at the intersection of 33rd and Sheridan Blvd in the City of Lincoln. Citizens and some professionals were somewhat skeptical of the capability of this roundabout to improve traffic …
Dynamic Evaluation Of New York State’S Aluminum Pedestrian Signal Pole System, Scott K. Rosenbaugh, Ronald K. Faller, Karla A. Lechtenberg, Robert W. Bielenberg, Dean L. Sicking, John D. Reid
Dynamic Evaluation Of New York State’S Aluminum Pedestrian Signal Pole System, Scott K. Rosenbaugh, Ronald K. Faller, Karla A. Lechtenberg, Robert W. Bielenberg, Dean L. Sicking, John D. Reid
Mid-America Transportation Center: Final Reports and Technical Briefs
The New York State Department of Transportation (NYSDOT) mounts pedestrian “hand/man” signals to aluminum
poles and uses frangible transformer bases to allow the system to break away. However, engineers at NYSDOT believed that the material properties of the aluminum poles themselves would allow the pedestrian signal poles to break away without the use of transformer bases. Elimination of the frangible transformer base would result in significant savings.
An aluminum pedestrian signal pole system was erected at the Valmont testing facility and tested with the Valmont- MwRSF/UNL pendulum with crushable nose in accordance with NCHRP Report No. 350 test designation no. …
Effects Of Aggregate Angularity On Mix Design Characteristics And Pavement Performance, Yong-Rak Kim, Leonardo T. Souza
Effects Of Aggregate Angularity On Mix Design Characteristics And Pavement Performance, Yong-Rak Kim, Leonardo T. Souza
Mid-America Transportation Center: Final Reports and Technical Briefs
This research targeted two primary purposes: to estimate current aggregate angularity test methods and to evaluate current aggregate angularity requirements in the Nebraska asphalt mixture/pavement specification. To meet the first research objective, various aggregate angularity tests were estimated with the same sets of aggregates and were compared by investigating their characteristics on testing repeatability, cost, testing time, workability, and sensitivity of test results. For the second objective, the effect of aggregate angularity on mixture performance was investigated by conducting laboratory performance tests (the uniaxial static creep test and the indirect tensile fracture energy test) of five mixes designed with different …
Steel Box System Monitoring Of N-2 Over I-80 Bridge, Atorod Azizinamini
Steel Box System Monitoring Of N-2 Over I-80 Bridge, Atorod Azizinamini
Mid-America Transportation Center: Final Reports and Technical Briefs
The previously performed market analysis of bridge material in the range of short to medium span length indicates a declining trend for steel girders during the last two decades. The “simple for dead, continuous for live load” is a new method of bridge construction aiming at reducing the steel girder construction expenses and in essence enhancing the steel girders’ competitiveness in the short to medium span length bridges. This method of construction takes the advantage of the simple span construction as well as reduction of the forces in the bridge elements due to the continuous span behavior. The continuity of …
Moisture Sensitivity Of Hot Mix Asphalt (Hma) Mixtures In Nebraska – Phase Ii, Yong-Rak Kim, Hoki Ban, Ingryd Pinto
Moisture Sensitivity Of Hot Mix Asphalt (Hma) Mixtures In Nebraska – Phase Ii, Yong-Rak Kim, Hoki Ban, Ingryd Pinto
Mid-America Transportation Center: Final Reports and Technical Briefs
As a consequential effort to the previous NDOR research project (P564) on moisture damage, this report presents outcomes from this project incorporated with the previous project. Performance changes and fundamental material characteristics associated with moisture damage due to various anti-stripping additives in asphalt mixtures are studied through various experimental approaches and a numerical simulation. Three additives (i.e., one reference additive, hydrated lime, and two alternative additives: fly ash and cement) are investigated by adding them into two types of mixes (SP2 for low-traffic-volume roadways and SP5 for high-traffic-volume roadways) where two different asphalt binders (PG 64-22 for the SP2 mix …
Use Of Ground Penetrating Radar For Construction Quality Assurance Of Concrete Pavement, George Morcous Ph.D., Ece Erdogmus
Use Of Ground Penetrating Radar For Construction Quality Assurance Of Concrete Pavement, George Morcous Ph.D., Ece Erdogmus
Mid-America Transportation Center: Final Reports and Technical Briefs
Extracting concrete cores is the most common method for measuring the thickness of concrete pavement for construction quality control. Although this method provides a relatively accurate thickness measurement, it is destructive, labor intensive, and time consuming. Moreover, concrete cores are usually taken approximately every 750 ft, which may be inadequate for estimating the actual thickness profile of a pavement section; however extracting more cores would damage the pavement extensively and increase the labor cost and time excessively. Ground Penetrating Radar (GPR) is a well-established technique for subsurface exploration. Recently, GPR has been used for several transportation applications, such as measuring …
Application Of Ultra-High Performance Concrete To Bridge Girders, Maher K. Tadros Ph.D., P.E., George Morcous Ph.D.
Application Of Ultra-High Performance Concrete To Bridge Girders, Maher K. Tadros Ph.D., P.E., George Morcous Ph.D.
Mid-America Transportation Center: Final Reports and Technical Briefs
Ultra-High Performance Concrete (UHPC) is a new class of concrete that has superior performance characteristics compared to conventional concrete. The enhanced strength and durability properties of UHPC are mainly due to optimized particle gradation that produces a very tightly packed mix, extremely low water to powder ratio, and use of steel fibers. The unique strength and durability properties of UHPC make it an attractive material for precast prestressed bridge girder construction. However, commercial UHPC mixes currently available in the US market cost about 10 times the cost of conventional concrete mixes, in addition to the need for special mixing and …