Engineering Commons^™

Development Of Guideline For The Use Of Geosynthetics In Different Roadway Layered System In Nebraska, Jongwan Eun, Seunghee Kim, Daniel Robertson, Yusuf Alhowaidi, Hung Van, Laith Ibdah

Nebraska Department of Transportation: Research Reports

This study evaluated the design properties of the geosynthetic reinforced soils for the roadway pavement and compared the reinforcing performance depending on different geosynthetics and soil types, particularly for a subgrade layer in Nebraska. The results obtained from a large direct shear test, pullout test, and soil chamber test with a dynamic cone penetrometer (DCP) showed that geosynthetic improves soil properties associated with the pullout and interface shear resistance, strength related parameters. The Large Scale Tracking Wheel Test also showed how the performance of biaxial geogrid reinforced pavement improved the strength/stiffness and reduced the total permanent deformation and pressure acting …

Nebraska Balanced Mix Design – Phase I, Farzad Yazdipanah, Mahdieh Khedmati, Hamzeh Haghshenas

Nebraska Department of Transportation: Research Reports

Balanced mix design (BMD) is an alternative concept for designing asphalt mixtures that mainly focuses on performance of mixtures rather than only volumetric analysis. Using this concept, it would be possible to account for the incorporation of recycled asphalt mixtures, warm technology, polymers, rejuvenators, and other foreign additives, as well as external effective factors on the mix design such as environmental effects. This project sought to investigate performance-based methodologies for the asphalt mix design by taking a step to develop a preliminary Nebraska BMD framework. With that, selection of appropriate performance tests, finding a functional laboratory aging protocol, and defining …

Colloidal Silica: Cement Enhancing Admixture Product Evaluation, Lieska Halsey, David Hansen

Nebraska Department of Transportation: Research Reports

As Class F- fly ash (F-ash) becomes scarce, PCC engineers will look to other supplemental cementitious materials (SCM) to replace F-ash and its ASR mitigating properties. Colloidal silica (CS), or nano-silica, has been shown to mitigate ASR at certain replacement levels; however, CS cannot be a full replacement of F-ash. Engineers at the Nebraska Department of Transportation (NDOT) learned of CS from a presentation given by Intelligent Concrete, Inc. at the 2019 Nebraska Concrete Professionals Association Conference and decided to investigate the potential use of CS in NDOT concrete mix designs.

Evaluation Of Tie-Bar Anchoring Methods: Non-Shrink Grout Vs. Epoxy, Wally Heyen, Lieska Halsey, Tim Krason, Brandon Varilek, David Hansen

Nebraska Department of Transportation: Research Reports

Tie bars are epoxy coated steel bars that connect the longitudinal joints in concrete pavement. Tie bars prevent faulting and joint separation between lanes Tie bars can be placed into the plastic concrete or inserted after curing by drilling and anchoring with epoxy or non-shrink grout. The specification for the tie bars requires the use of a No. 5 bar, 18 inches long and shall meet ASTM A775 / A775M [1], Section 1020.The Nebraska Department of Transportation “Standard Specifications for Highway Construction,” (Section 603.03) requires contractors to mechanically insert tie bars into the face of pavements during construction. Tie bars …

Development Of High-Performance Rapid Patching Materials For Pavement Repair, Gholami Shayan, Jiong Hu, Yong-Rak Kim

Nebraska Department of Transportation: Research Reports

Concrete pavements exhibiting severe distresses which require patching are commonly observed in the concrete pavement in Nebraska. Due to the requirements of opening pavement to traffic after placing the rapid patching materials, it is essential for that concrete to achieve high early strength. To ensure this, a high cement content and chloride-based accelerators are currently used in the Nebraska Department of Transportation (NDOT) Portland cement-based rapid-patching materials. Besides its associated high cost, high cement content tends to result in a less stable mix with high shrinkage, high heat of hydration, and high cracking potential. In addition, using chloride-based accelerators has …

Investigation Of Dsr Test Methods To Determine Binder Low Temperature Properties, Kommidi Santosh, Yong-Rak Kim

Nebraska Department of Transportation: Research Reports

The low temperature rheology of bituminous binders is of great interest because low temperature cracking is one of the primary asphalt pavement failure modes observed in cold-climate places such as Nebraska. Low temperature binder characterization/grading has been primarily conducted using the bending beam rheometer (BBR), while the dynamic shear rheometer (DSR) can alternatively be used to characterize the low temperature properties of binders with the recent advancement of DSR equipment that can cover a wide range of testing temperatures. This study investigates alternative testing-analysis methods using the DSR to determine low temperature asphalt binder properties that have been measured by …

Research On High-Rap Asphalt Mixtures With Rejuvenators - Phase Ii, Hamzeh Haghshenas, Gabriel Nsengiyumva, Yong-Rak Kim, Kommidi Santosh, Soroosh Amelian

Nebraska Department of Transportation: Research Reports

A previous study by the authors have demonstrated effectiveness of three rejuvenators: R1 (triglyceride/fatty acid: agriculture-tech based), R2 (aromatic extract: petroleum-tech based), and R3 (tall oil: green-tech based) on rejuvenating properties of the aged binder. In that study, it was observed that the rejuvenators made high-RAP mixtures softer and more compliant, which may increase the rutting potential, while they simultaneously improve cracking resistance of the high-RAP materials. Research outcomes and findings from the previous study resulted in consequential research needs for more specific investigation of high-RAP mixtures with rejuvenators in order to achieve realistic implementation into future high-RAP paving projects …

Investigating The Interaction Of Ndot Hot-Pour Pcc Joint Sealant And Penetrating Concrete Sealers, Bruce Barrett, Dale Byre, Wally Heyen, Lieska Halsey, David Hansen

Nebraska Department of Transportation: Research Reports

Based on the field observations on NE-83, PCS potentially impacts the bond between the concrete and hot-pour sealant after application. If penetrating sealers break the interfacial bond after application, concrete pavements could become compromised and subject to freeze-thaw damage, chloride attack, and other deleterious effects.

The results show that discoloration occurred when applying the five PCS products to the NE-3405 hot-pour sealed testing blocks. All three test methods of application; spraying, 1-min, and 5-min soaks, caused discoloration. The level of discoloration increased with the duration of contact with the PCS. Despite discoloration, none of the five PCS products caused de-bonding …

New Mixture Additives For Sustainable Bituminous Pavements, Gabriel Mukristu Nsengiyumva, Kommidi Santosh, Yong-Rak Kim, Helan Xu, Yiqi Yang

Nebraska Department of Transportation: Research Reports

In an effort to improve mechanical properties of asphalt concrete, an exploratory research using mixture additives was attempted. Two different types of additives on two material scales were used: asphalt concrete (AC) level and binder level. At the start of this study, the effect of natural cornhusk fibers on the resistance of two types of AC mixtures on cracking were tested for hot-mix asphalt (HMA) and cold-mix asphalt (CMA). The results showed slight improvements in cracking resistance in cornhusk reinforced HMA, and in the case of the CMA, marshal flow. Overall, based on the test results, cornhusk-reinforced HMA and CMA …

Hot Applied Sealant Bond Test For Joints With Penetrating Sealers, Lieska Halsey

Nebraska Department of Transportation: Research Reports

Recently a concern has been raised for hot applied sealant bond for joints with penetrating sealers. The objective of this study will be to determine if the bond between the sealant and the concrete is compromised by the sealer currently approved to be used in Nebraska. The expected results will be that the bond is not compromised and is serving for the expected joint service life.

Compressive Strength Of Concrete Cylinders By Different Preparation Methods: Sulphur, Neoprene Pads And Grinding, Wally Heyen, Lieska Halsey

Nebraska Department of Transportation: Research Reports

The purpose of this evaluation is to compare the effects of four types of cylinder preparation methods prior to compressive strength testing in accordance to ASTM C 39.

Design And Evaluation Of Modified Centerline Rumble Strips, Yong-Rak Kim, Tae Sun You, Laurence Rilett

Nebraska Department of Transportation: Research Reports

A centerline rumble strip (CLRS) is primarily installed on the centerline of undivided two-lane and two-way roadways to alert drivers that they are moving out of their intended travel lane. The main purpose of CLRSs is to reduce crossover collisions typically caused by inattentive, distracted, drowsy, or fatigued drivers. Despite the safety benefits, CLRSs that were milled over or adjacent to the centerline joint may increase or accelerate the deterioration and degradation of the pavement structure, which has been observed in Nebraska pavements. In this research project, new (or modified) CLRS designs were sought to reduce pavement damage, while satisfying …

Use Of Recycled Crushed Concrete (Rcc) Fines For Potential Soil Stabilization, Lindeman Mark, Varilek Brandon, Lieska Halsey, Rick Gloe, Maria Olomi

Nebraska Department of Transportation: Research Reports

This study evaluated the use of Recycled Crushed Concrete (RCC) Fines for potential soil stabilization. Soil stabilization is the enhancement of subgrade stability to improve the constructability of successive pavement layers. Use of RCC fines may not only provide less costly alternatives for subgrade stabilization, but their use may also alleviate landfill disposal challenges.

Development Of Semi-Circular Bending (Scb) Fracture Test For Bituminous Mixtures, Gabriel Nsengiyumva

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Granted that most distresses in asphalt (flexible) concrete (AC) pavements are directly related to fracture, it becomes clear that identifying and characterizing fracture properties of AC mixtures is a critical step towards a better pavement design. This thesis examines the testing variables of a reliable and practical semicircular bending (SCB) test for evaluating the fracture characteristics of asphalt concrete mixtures at intermediate service temperature conditions. The first part of this thesis investigates the repeatability of the SCB fracture test method by integrating a statistical-experimental approach to identify testing variables of the SCB test that result in repeatable test results. Toward …

Development Of A Semicircular Bend (Scb) Test Method For Performance Testing Of Nebraska Asphalt Mixtures, Gabriel Nsengiyumva, Yong-Rak Kim, Taesun You

Nebraska Department of Transportation: Research Reports

No abstract provided.

Mitigating Pavement Edge Drop Off, Wayne Jensen, Niles Uerling

Nebraska Department of Transportation: Research Reports

The objective of this research was to investigate and document practices currently being used by the Nebraska Department of Roads (NDOR) districts and other State DOTs to mitigate pavement edge drop off. The NDOR has developed (or borrowed) and is currently incorporating into its standard practices several procedures that significantly decrease the incidence and magnitude of pavement edge-drop off. As these practices become more fully integrated into highway reconstruction projects, pavement edge drop off is expected to decrease dramatically. Localized areas of pavement edge drop off along paved lanes with bare or vegetated shoulders were noted as posing particular problems …

Nebraska Data Collection, Keyvan Zare Rami, Yong-Rak Kim

Nebraska Department of Transportation: Research Reports

Automated pavement performance data collection is a method that uses advanced technology to collect detailed road surface distress information at traffic speed. Agencies are driven to use automated survey techniques to enhance or replace their current manual distress survey because of the advantages of objective measurements, safety benefits, and reduced measurement time. As agencies move toward the transition to fully automated data collection methods, there are common concerns regarding how the output of the new method will match the current manual survey ratings and how they will be adopted into the existing Pavement Management System (PMS). This study evaluates the …

Development And Evaluation Of Weak-Post W-Beam Guardrail In Mow Strips, Scott K. Rosenbaugh, Ronald K. Faller, Karla A. Lechtenberg, James C. Holloway

Nebraska Department of Transportation: Research Reports

The objective of this study was to adapt and evaluate a weak-post, W-beam guardrail system for use within mow strips and other pavements. The weak-post guardrail system was originally designed as the MGS bridge rail and has also been adapted for use on culverts. It was envisioned that the weak-post design would absorb the impact forces and prevent damage to the mow strips, thereby minimizing maintenance and repair costs.

Evaluation of the weak posts in mow strips began with three rounds of dynamic bogie testing. Round 1 of bogie testing showed that 4-in. (102-mm) thick concrete would sustain only minor …

Evaluation Of Thin Asphalt Overlay Practice Preserving Nebraska's Asphalt Pavement, Soohyok Im, Yong-Rak Kim, Hamzeh Haghshenas Fatmehsari, Gabriel Nsengiyumva, Taesun You

Nebraska Department of Transportation: Research Reports

No abstract provided.

Pavement Quality Indicators, Connor Villanueva, Wayne Jensen

Nebraska Department of Transportation: Research Reports

No abstract provided.

Optimized Aggregates Gradations For Portland Cement Concrete Mix Designs Evaluation, Wally Heyen, Lieska Halsey, Robert Rea, Mick Syslo

Nebraska Department of Transportation: Research Reports

No abstract provided.

Layer Moduli Of Nebraska Pavements For The New Mechanistic Empirical Pavement Design Guide, Soohyok Im, Yong-Rak Kim, Hoki Ban

Nebraska Department of Transportation: Research Reports

No abstract provided.

Effects Of Aggregate Angularity On Mix Design Characteristics And Pavement Performance, Leonardo T. Souza, Yong-Rak Kim

Nebraska Department of Transportation: Research Reports

No abstract provided.

Effects Of Aggregate Angularity On Mix Design Characteristics And Pavement Performance, Yong-Rak Kim, Leonardo T. Souza

Nebraska Department of Transportation: Research Reports

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 …

Moisture Sensitivity Of Hot Mix Asphalt Mixtures In Nebraska -- Phase Ii, Ingryd Pinto, Hoki Ban, Yong-Rak Kim

Nebraska Department of Transportation: Research Reports

No abstract provided.

Use Of Ground Penetrating Radar For Construction Quality Assurance O Concrete Pavement, George Morcous, Ece Erdogmus

Nebraska Department of Transportation: Research Reports

No abstract provided.

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 …

Research On Fatigue Of Asphalt Mixtures And Pavements In Nebraska, Francisco Thiago S. Aragao, Yong-Rak Kim, Junghun Lee

Nebraska Department of Transportation: Research Reports

No abstract provided.

Pavement Quality Indicators Study, Wayne Jensen Ph.D., Cody Kluver

Mid-America Transportation Center: Final Reports and Technical Briefs

The Nebraska Department of Roads (NDOR) conducts annual examinations of the Nebraska’s interstate and federal high-way pavements. During these examinations, numerous indicators of pavement quality are measured directly or are com-piled from parameters recorded by a vehicle passing over the pavement section. Parameters are documented and analyzed for each one-tenth mile segment. A number of pavement sections where innovative features have been incorporated were selected by the NDOR for comparison to nearby conventional pavement sections. This study used data recorded by the NDOR as well as field observations to develop a comparison between two pavement sections, one with innovative fea-tures …

Investigation Of Asphalt Pavement Analyzer Testing Program In Nebraska, Minki Hong, Yong-Rak Kim

Mid-America Transportation Center: Final Reports and Technical Briefs

The asphalt pavement analyzer (APA) has been widely used to evaluate hot-mix asphalt (HMA) rutting potential in mix design and quality control – quality assurance (QC-QA) applications, because the APA testing and its data analyses are relatively simple, rapid, and easy. However, as demonstrated in many studies and also experienced by the state of Nebraska, the APA testing is in question due to its high testing variability and a lack of sufficient correlation with actual filed performance. The primary objective of this research was to find critical materials and/or mixture design factors affecting APA test results so as to eventually …