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Evaluation Of Opportunities And Challenges Of Using Inrix Data For Real-Time Performance Monitoring And Historical Trend Assessment, Anuj Sharma, Vesal Ahsani, Sandeep Rawat

Nebraska Department of Transportation: Research Reports

In recent years there has been a growing desire for the use of probe vehicle technology for congestion detection and general infrastructure performance assessment. Unlike costly traditional data collection by loop detectors, wide-area detection using probe-sourced traffic data is significantly different in terms of measurement technique, pricing, coverage, etc. This affects how the new technology is applied and used to solve current traffic problems such as traffic incident management and roadway performance assessment. This report summarizes the experiences and lessons learned while using probe data for traffic operations and safety management in the state of Nebraska and makes recommendations for …

Increased Span Length For The Mgs Long-Span Guardrail System Part Iii: Failure Analysis, Sagheer A. Ranjha, Robert W. Bielenberg, John D. Reid, Ronald K. Faller

Nebraska Department of Transportation: Research Reports

The objective of this research study was to review and analyze the system failure observed during crash testing of an increased span length for the MGS long-span guardrail system in test no. MGSLS-2. Test no. MGSLS-2 was a full-scale crash test conducted on the MGS long-span guardrail with a span length of 311⁄4 ft (9.5 m). This test utilized universal breakaway steel posts (UBSPs) adjacent to the long span in lieu of the controlled release terminal (CRT) wood posts used in previous long span systems.

An engineering analysis was undertaken to review the downstream end anchorage failure observed in test …

Evaluation Of Adjustable Continuity Joint Variations For Use In The Restore Barrier, Scott Rosenbaugh, Jennifer D. Schmidt, Ronald K. Faller, James C. Holloway

Nebraska Department of Transportation: Research Reports

During MASH TL-4 full-scale crash testing of the RESTORE barrier, concrete cracking and spalling was observed on the barrier beams that would likely require repairs or replacement. This study sought to evaluate joint design alternatives for use in the RESTORE barrier in order to limit the amount of system damage. Three variations of the Adjustable Continuity Joint (ACJ) were identified as potential modifications: 1) incorporating rubber bearing pads within the ACJ, 2) utilizing normal weight concrete instead of lightweight concrete, and 3) incorporating a steel end cap into the ends of the beam segments.

Four dynamic component tests were conducted …

Evaluation Of Floorpan Tearing And Cable Splices For Cable Barrier Systems, Scott K. Rosenbaugh, Jason A. Hartwell, Robert W. Bielenberg, Ronald K. Faller, James C. Holloway, Karla A. Lechtenberg

Nebraska Department of Transportation: Research Reports

This research effort consisted of two objectives related to components of a prototype cable barrier system. The first objective was to mitigate the potential for vehicle floorpan tearing by modifying the cable guardrail posts. A bogie vehicle was equipped with a simulated floorpan designed to replicate the height, thickness, and strength of the floorpan of a Kia Rio vehicle. Baseline testing demonstrated that the top of the Midwest Weak Post (MWP) would contact, and crease the simulated floorpan, which matched the damage observed in actual full-scale vehicle crash tests. Once the test setup provided the desired results, various post configurations …

Mash Test No. 3-10 Of A Non-Proprietary, High-Tension Cable Median Barrier For Use In 6h:1v V-Ditch (Test No. Mwp-8), Dylan T. Meyer, Karla A. Lechtenberg, Ronald K. Faller, Robert W. Bielenberg, Scott K. Rosenbaugh, John D. Reid

Nebraska Department of Transportation: Research Reports

The Midwest States Pooled Fund Program has been developing a prototype design for a non-proprietary, high-tension cable median barrier for use in a 6H:1V V-ditch. This system incorporates four evenly spaced cables, Midwest Weak Posts (MWP) spaced at 8 to 16 ft (2.4-4.9 m) intervals, and a bolted, tabbed bracket to attach three or four cables to the sides of each post. According to the Manual for Assessing Safety Hardware (MASH) testing matrix for cable barriers installed within a 6H:1V median V-ditch, a series of eight full-scale tests are required to evaluate the safety performance of a system. A ninth …

Length Of Need And Minimum System Length For F-Shape Portable Concrete Barrier, Robert W. Bielenberg, Dylan T. Meyer, Ronald K. Faller, John D. Reid

Nebraska Department of Transportation: Research Reports

Portable concrete barrier (PCB) systems are often used to redirect errant vehicles through a combination of inertial resistance, lateral friction loads, and tensile loads developed from the mass and friction of the barrier segments. State departments of transportation (DOTs) and other end users may wish to utilize minimal length PCB installations to shield a hazard or work zone or limit the number of barriers required on the upstream and downstream ends to reduce overall system length. However, concerns with the performance of shorter PCB installations include increased lateral deflections and working widths and barrier pocketing. Additionally, no impact testing has …

Testing And Evaluation Of Mash Tl-3 Transition Between Guardrail And Portable Concrete Barriers, Robert W. Bielenberg, Jessica L. Lingenfelter, Justine E. Kohtz, Ronald K. Faller, John D. Reid

Nebraska Department of Transportation: Research Reports

Three full-scale vehicle crash tests were conducted according to the Manual for Assessing Safety Hardware (MASH) Test Level 3 (TL-3) safety performance criteria on a transition between the Midwest Guardrail System (MGS) and a portable concrete barrier (PCB) system. The transition system utilized for test nos. MGSPCB-1 through MGSPCB-3 consisted of a standard MGS that overlapped a series of F- shape PCB segments that approached the MGS at a 15H:1V flare. In the overlapped portion of the barrier systems, uniquely-designed blockout holders and a specialized W-beam end shoe mounting bracket were used to connect the systems.

In test no. MGSPCB-1, …

Increased Span Length For The Mgs Long-Span Guardrail System Part Ii: Full-Scale Crash Testing, Dylan T. Meyer, John D. Reid, Karla A. Lechtenberg, Robert W. Bielenberg, Ronald K. Faller

Nebraska Department of Transportation: Research Reports

The objective of this research study was to design and evaluate the MGS long-span design for use with unsupported spans greater than 25 ft (7.6 m). Two full-scale crash tests were conducted to evaluate the MGS long-span system with increased span lengths and the use of UBSP posts adjacent to the long span. Both tests were conducted according to the TL- 3 criteria outlined in MASH. Both test nos. MGSLS-1 and MGSLS-2 were conducted with the 2270P vehicle impacting their respective critical impact points at a speed of 62 mph (100 km/h) and an angle of 25 degrees. Test no. …

Evaluation Of Tack Coating Practices For Asphalt Overlays In Nebraska, Soroosh Amelian, Yong-Rak Kim

Nebraska Department of Transportation: Research Reports

The strength of the bond between asphalt layers affects the lifespan of pavement structures. It is also a key factor in preventing major pavement distresses, such as slippage cracking and delamination. This research project evaluates and compares the effectiveness and performance of different tack coating approaches to ensure the proper bond strength is achieved in asphalt concrete (AC) interlayers through an experimental study. Various tack coat materials, including different types of emulsified asphalt and asphalt binders, at multiple application rates and dilution ratios were investigated. In the first part of this study, laboratory-prepared samples were used to evaluate the sensitivity …

Assessing Passenger Car Equivalency Factors For High Truck Percentages, Jianan Zhou, Laurence Rilett, Elizabeth Jones

Nebraska Department of Transportation: Research Reports

The Passenger Car Equivalent (PCE) values in the Highway Capacity Manual (HCM) 2010 might not be valid for western Nebraska freeway conditions. This is because: 1) Interstate 80 (I-80) experiences high truck percentages (25% to 60%), while the HCM provides PCE values up to 25% of the truck percentage; 2) the average speed of trucks are observed lower than passenger cars, which is incompatible with the HCM assumption that the free speed of all vehicle types is the same at level terrain; and 3) it is unclear whether the “average” truck used in the simulation study for PCE values in …