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Development Of Non-Petroleum-Based Binders For Use In Flexible Pavements – Phase Ii, R. Christopher Williams, Elvira Joana Joana Ferreira Ferreira Peralta, Ka Lai Nieve Ng Puga 2017 Iowa State University

Development Of Non-Petroleum-Based Binders For Use In Flexible Pavements – Phase Ii, R. Christopher Williams, Elvira Joana Joana Ferreira Ferreira Peralta, Ka Lai Nieve Ng Puga

R. Christopher Williams

Bio-binders can be utilized as asphalt modifiers, extenders, and replacements for conventional asphalt in bituminous binders. From the rheology results of Phase I of this project, it was found that the bio-binders tested had good performance, similar to conventional asphalt, except at low temperatures. Phase II of this project addresses this shortcoming and evaluates the Superpave performance of laboratory mixes produced with the enhanced bio-binders. The main objective of this research was to develop a bio-binder capable of replacing conventional asphalt in flexible pavements by incorporating ground tire rubber (GTR) into bio-oil derived from fast pyrolysis of agriculture and forestry ...


Investigation Of Warm-Mix Asphalt For Iowa Roadways, Phase Ii, Ashley F. Buss, R. Christopher Williams 2017 Iowa State University

Investigation Of Warm-Mix Asphalt For Iowa Roadways, Phase Ii, Ashley F. Buss, R. Christopher Williams

R. Christopher Williams

Phase II of this study further evaluated the performance of plant-produced warm-mix asphalt (WMA) mixes by conducting additional mixture performance tests at a broader range of temperatures, adding additional pavements to the study, comparing virgin and recovered binder properties, performing pavement condition surveys, and comparing survey data with the Mechanistic Empirical Pavement Design Guide (MEPDG) forecast for pavement damage over 20 years of service life. Further objectives detailing curing behavior, quality assurance testing, and hybrid technologies were as follows: * Compare the predicted and observed field performance of existing WMA trials produced in the previous Phase I study to that of ...


Assessment Of Asphalt Interlayer Designed On Jointed Concrete, R. Christopher Williams, Andrew A. Cascione 2017 Iowa State University

Assessment Of Asphalt Interlayer Designed On Jointed Concrete, R. Christopher Williams, Andrew A. Cascione

R. Christopher Williams

Reflective cracking in hot mix asphalt (HMA) overlays has been a common cause of poor pavement performance in Iowa for many years. Reflective cracks commonly occur in HMA overlays when deteriorated portland cement concrete is paved over with HMA. This results in HMA pavement surfaces with poor ride quality and increased transportation maintenance costs. To delay the formation of cracks in HMA overlays, the Iowa Department of Transportation (Iowa DOT) has begun to implement a crack-relief interlayer mix design specification. The crack-relief interlayer is an asphalt-rich, highly flexible HMA that can resist cracking in high strain loading conditions. In this ...


Reflective Crack Mitigation Guide For Flexible Pavements Final Report, R. Christopher Williams, Ashley F. Buss, Can Chen 2017 Iowa State University

Reflective Crack Mitigation Guide For Flexible Pavements Final Report, R. Christopher Williams, Ashley F. Buss, Can Chen

R. Christopher Williams

Reflective cracks form in pavements when hot-mix asphalt (HMA) overlays are placed over jointed and/or severely cracked rigid and flexible pavements. In the first part of the research, survival analysis was conducted to identify the most appropriate rehabilitation method for composite pavements and to evaluate the influence of different factors on reflective crack development. Four rehabilitation methods, including mill and fill, overlay, heater scarification (SCR), and rubblization, were analyzed using three performance indicators: reflective cracking, international roughness index (IRI), and pavement condition index (PCI). It was found that rubblization can significantly retard reflective cracking development compared to the other ...


Development Of Non-Petroleum-Based Binders For Use In Flexible Pavements – Phase Ii, R. Christopher Williams, Elvira Joana Joana Ferreira Ferreira Peralta, Ka Lai Nieve Ng Puga 2017 Iowa State University

Development Of Non-Petroleum-Based Binders For Use In Flexible Pavements – Phase Ii, R. Christopher Williams, Elvira Joana Joana Ferreira Ferreira Peralta, Ka Lai Nieve Ng Puga

R. Christopher Williams

Bio-binders can be utilized as asphalt modifiers, extenders, and replacements for conventional asphalt in bituminous binders. From the rheology results of Phase I of this project, it was found that the bio-binders tested had good performance, similar to conventional asphalt, except at low temperatures. Phase II of this project addresses this shortcoming and evaluates the Superpave performance of laboratory mixes produced with the enhanced bio-binders. The main objective of this research was to develop a bio-binder capable of replacing conventional asphalt in flexible pavements by incorporating ground tire rubber (GTR) into bio-oil derived from fast pyrolysis of agriculture and forestry ...


Assessment Of Nondestructive Testing Technologies For Quality Control/Quality Assurance Of Asphalt Mixtures, Jeramy C. Ashlock, R. Christopher Williams, Hosin David Lee, Shibin Lin, Hanjun Kim, Jeremy Nash 2017 Iowa State University

Assessment Of Nondestructive Testing Technologies For Quality Control/Quality Assurance Of Asphalt Mixtures, Jeramy C. Ashlock, R. Christopher Williams, Hosin David Lee, Shibin Lin, Hanjun Kim, Jeremy Nash

R. Christopher Williams

Asphalt pavements suffer various failures due to insufficient quality within their design lives. The American Association of State Highway and Transportation Officials (AASHTO) Mechanistic-Empirical Pavement Design Guide (MEPDG) has been proposed to improve pavement quality through quantitative performance prediction. Evaluation of the actual performance (quality) of pavements requires in situ nondestructive testing (NDT) techniques that can accurately measure the most critical, objective, and sensitive properties of pavement systems. The purpose of this study is to assess existing as well as promising new NDT technologies for quality control/quality assurance (QC/QA) of asphalt mixtures. Specifically, this study examined field measurements ...


Development Of Non-Petroleum Based Binders For Use In Flexible Pavements, R. Christopher Williams 2017 Iowa State University

Development Of Non-Petroleum Based Binders For Use In Flexible Pavements, R. Christopher Williams

R. Christopher Williams

Bio-oils can be implemented as binders to help reduce the pavement industry’s reliance on fossil fuels.


Development Of Bio-Based Polymers For Use In Asphalt, R. Christopher Williams, Andrew A. Cascione, Eric W. Cochran, Nacú B. Hernández 2017 Iowa State University

Development Of Bio-Based Polymers For Use In Asphalt, R. Christopher Williams, Andrew A. Cascione, Eric W. Cochran, Nacú B. Hernández

R. Christopher Williams

Asphalt binder is typically modified with poly type (styrene-butadiene-styrene or SBS) polymers to improve its rheological properties and performance grade. The elastic and principal component of SBS polymers is butadiene. For the last decade, butadiene prices have fluctuated and significantly increased, leading state highway agencies to search for economically viable alternatives to butadiene based materials. This project reports the recent advances in polymerization techniques that have enabled the synthesis of elastomeric, thermoplastic, block-copolymers (BCPs) comprised of styrene and soybean oil, where the “B” block in SBS polymers is replaced with polymerized triglycerides derived from soybean oil. These new breeds of ...


Performance Of Recycled Asphalt Shingles In Hot Mix Asphalt, R. Christopher Williams, Andrew A. Cascione, Jianhua Yu, Debra Haugen, Mihai Marasteanu, Jim McGraw 2017 Iowa State University

Performance Of Recycled Asphalt Shingles In Hot Mix Asphalt, R. Christopher Williams, Andrew A. Cascione, Jianhua Yu, Debra Haugen, Mihai Marasteanu, Jim Mcgraw

R. Christopher Williams

State highway agencies are increasingly intersted in using recycled asphalt shingles (RAS) in hot mix asphalt (HMA) applications, yet many agencies share common questions about the effect of RAS on the performance of HMA. Previous research has allowed for only limited laboratory testing and field surveys. The complexity of RAS materials and lack of past experiences led to the creation of Transportation Pooled Fund (TPF) Program TPF-5(213). The primary goal of this study is to address research needs of state DOT and environmental officials to determine the best practices for the use of recycled asphalt shingles in hot-mix asphalt ...


Investigation Of Warm-Mix Asphalt For Iowa Roadways, Phase Ii, Ashley F. Buss, R. Christopher Williams 2017 Iowa State University

Investigation Of Warm-Mix Asphalt For Iowa Roadways, Phase Ii, Ashley F. Buss, R. Christopher Williams

R. Christopher Williams

Phase II of this study further evaluated the performance of plant-produced warm-mix asphalt (WMA) mixes by conducting additional mixture performance tests at a broader range of temperatures, adding additional pavements to the study, comparing virgin and recovered binder properties, performing pavement condition surveys, and comparing survey data with the Mechanistic Empirical Pavement Design Guide (MEPDG) forecast for pavement damage over 20 years of service life. Further objectives detailing curing behavior, quality assurance testing, and hybrid technologies were as follows: * Compare the predicted and observed field performance of existing WMA trials produced in the previous Phase I study to that of ...


Development Of Modulus-To-Temperature Relations For Hma Mixtures In Wisconsin, James Crovetti, Kathleen T. Hall, R. Christopher Williams 2017 Marquette University

Development Of Modulus-To-Temperature Relations For Hma Mixtures In Wisconsin, James Crovetti, Kathleen T. Hall, R. Christopher Williams

R. Christopher Williams

This report presents the findings of a research study conducted to develop modulus-to-temperature relations for HMA mixtures used in Wisconsin. Surface deflection data gathered from in-place HMA pavements was used to estimate the resilient modulus of the HMA layer at the various test temperatures. Laboratory resilient modulus testing was also conducted on recovered HMA cores to establish trends of HMA resilient modulus as a function of test temperature and load frequency. Prediction equations for estimating modulus-to-temperature trends were developed from laboratory testing to account for mixture-specific parameters, including fines content, air voids and binder content. Estimations of HMA modulus-to-temperature trends ...


Validation Of Gyratory Mix Design In Iowa, R. Christopher Williams, Ashley Buss, Marie Grace Joson Mercado, Hosin David Lee, Ashkan Bozorgzad 2017 Iowa State University

Validation Of Gyratory Mix Design In Iowa, R. Christopher Williams, Ashley Buss, Marie Grace Joson Mercado, Hosin David Lee, Ashkan Bozorgzad

R. Christopher Williams

The design number of gyrations (Ndesign) introduced by the Strategic Highway Research Program (SHRP) and used in the Superior Performing Asphalt Pavement (Superpave) mix design method has been commonly used in flexible pavement design throughout the US since 1996. Ndesign, also known as the compaction effort, is used to simulate field compaction during construction and has been reported to produce air voids that are unable to reach ultimate pavement density within the initial 2 to 3 years post-construction, potentially having an adverse impact on long-term performance. Other state transportation agencies have conducted studies validating the Ndesign for their specific regions ...


Investigation Of Warm-Mix Asphalt Using Iowa Aggregates, Ashley F. Buss, Mohamed H. Rashwan, R. Christopher Williams 2017 Iowa State University

Investigation Of Warm-Mix Asphalt Using Iowa Aggregates, Ashley F. Buss, Mohamed H. Rashwan, R. Christopher Williams

R. Christopher Williams

The implementation of warm-mix asphalt (WMA) is becoming more widespread with a growing number of contractors utilizing various WMA technologies. Early research suggests WMA may be more susceptible to moisture damage than traditional hot-mix asphalt (HMA) mixes. The objectives of this study are to test the binder and mix properties of WMA technologies for both field- and laboratory-produced mixes to determine the performance of WMA compared to traditional HMA. Field- and laboratory-produced mixes were studied. The laboratory-produced mixes compared HMA control mixes with WMA mixes that had the same mix design. The WMA technologies used for the laboratory study were ...


Materials Characterization And Analysis Of The Marquette Interchange Hma Perpetual Pavement, James Crovetti, Hani Titi, Aaron Coenen, Mohammed Elias, R. Christopher Williams, Xinjun Li 2017 Marquette University

Materials Characterization And Analysis Of The Marquette Interchange Hma Perpetual Pavement, James Crovetti, Hani Titi, Aaron Coenen, Mohammed Elias, R. Christopher Williams, Xinjun Li

R. Christopher Williams

This project focused on the characterization of materials used to construct the Hot Mix Asphalt (HMA) perpetual pavement within the Marquette Interchange and on the analysis of collected pavement response data to investigate the interactions between materials, environment, and traffic loadings. While these pavements are designed for a service life in excess of 50 years, to date there is insufficient field data to confirm this performance expectation. To help bridge this knowledge gap, this study included a mechanistic-empirical appraisal of the HMA perpetual pavement to provide predictions of key performance indicators over a fifty year service period. Laboratory testing was ...


Soft Elastomeric Capacitor Network For Strain Sensing Over Large Surfaces, Simon Laflamme, Husaam S. Saleem, Bharath K. Vasan, Randall L. Geiger, Degang J. Chen, Michael R. Kessler, Krishna Rajan 2017 Iowa State University

Soft Elastomeric Capacitor Network For Strain Sensing Over Large Surfaces, Simon Laflamme, Husaam S. Saleem, Bharath K. Vasan, Randall L. Geiger, Degang J. Chen, Michael R. Kessler, Krishna Rajan

Randall Geiger

Field applications of existing sensing solutions to structural health monitoring (SHM) of civil structures are limited. This is due to economical and/or technical challenges in deploying existing sensing solutions to monitor geometrically large systems. To realize the full potential of SHM solutions, it is imperative to develop scalable cost-effective sensing strategies. We present a novel sensor network specifically designed for strain sensing over large surfaces. The network consists of soft elastomeric capacitors (SECs) deployed in an array form. Each SEC acts as a surface strain gage transducing local strain into changes in capacitance. Results show that the sensor network ...


Large-Scale Flexible Membrane For Automatic Strain Monitoring Of Transportation Infrastructure, Simon Laflamme, Venkata D. Kolipara, Hussam S. Saleem, Randall L. Geiger 2017 Iowa State University

Large-Scale Flexible Membrane For Automatic Strain Monitoring Of Transportation Infrastructure, Simon Laflamme, Venkata D. Kolipara, Hussam S. Saleem, Randall L. Geiger

Randall Geiger

Structural Health Monitoring (SHM) of transportation infrastructures is a complex task, typically conducted by visual inspection due to the technical and economical constrains of existing health monitoring technologies. It results that health monitoring is highly dependent on scheduling and on the judgment of the inspectors, which can be costly and ineffective. Thus, it is fundamental to automate the SHM process to allow timely inspection, maintenance, and management of transportation infrastructure. The authors propose a flexible membrane that can be deployed over large surfaces, at low cost, for automatic and continuous monitoring of strains. The membrane, termed sensing skin, is constituted ...


Dynamic Amplification Factors For Railway Turnout Bearers In Switches And Crossings, Sakdirat Kaewunruen, Chayut Ngamkhanong, Rims Janeliukstis, Ruilin You 2017 University of Birmingham

Dynamic Amplification Factors For Railway Turnout Bearers In Switches And Crossings, Sakdirat Kaewunruen, Chayut Ngamkhanong, Rims Janeliukstis, Ruilin You

Sakdirat Kaewunruen


Railway infrastructure is nonlinear by nature, scientifically proven by its behav-iours, geometry and alignment, wheel-rail forces and operational parameters such as tractive efforts. It is often found that most train-turnout interaction models do not consider the time dependent ballast degradation. Such ballast degradation later causes differential settlement and aggravates impact forces acting on partial and unsupported sleepers and bearers. Fur-thermore, localised ballast breakages underneath any railseat increase the likelihood of cen-tre-bound cracks in railway sleepers and bearers due to the unbalanced support. This paper presents a numerical simulation of a standard-gauge concrete bearer at crossing panel, tak-ing into account the ...


Dynamic Responses Of Railway Ultra-High-Strength Concrete Sleepers Under Extreme Impact Loading, Sakdirat Kaewunruen, Alexander Remennikov, Shintaro Minoura 2017 University of Birmingham

Dynamic Responses Of Railway Ultra-High-Strength Concrete Sleepers Under Extreme Impact Loading, Sakdirat Kaewunruen, Alexander Remennikov, Shintaro Minoura

Sakdirat Kaewunruen

Ultra high strength concrete has been adopted recently in construction industry. Prestressed concrete sleepers (or railroad ties) are designed usually using high strength concrete (around 50-80 MPa) in order to carry and transfer the wheel loads from the rails to the ground and to maintain rail guage for safe train travels. The sleepers are installed as the crosstie beam support in railway track systems. They are subjected to impact loading conditions that are resulted from train operations over wheel or rail abnormalities, such as flat wheels, dipped rails, crossing transfers, rail squats, corrugation, etc. The magnitude of the shock load ...


Nonlinear Modelling And Analysis Of Moving Train Loads On Interspersed Railway Tracks, Sakdirat Kaewunruen, Tomasz Lewandrowski, Kritditorn Chamniprasart 2017 University of Birmingham

Nonlinear Modelling And Analysis Of Moving Train Loads On Interspersed Railway Tracks, Sakdirat Kaewunruen, Tomasz Lewandrowski, Kritditorn Chamniprasart

Sakdirat Kaewunruen


The interspersed pattern sleeper of railway track, which is a replacement of old timber sleeper with concrete, is often used as a temporary maintenance for second or third class railway lines with aging timber sleepers. However, their negative effect on the railway has to be taken into an account. The numerical simulations of interspersed sleeper railway tracks are conducted as well as the plain ones using a finite element program, STRAND7, so that the precise numerical models can be established. Two moving point loads, 100 kN each, are simulated to represent a passenger train bogie moving along each rail in ...


Opportunities And Benefits Of Commercial Truck Platooning, Greg Shaver, Katie England 2017 Purdue University

Opportunities And Benefits Of Commercial Truck Platooning, Greg Shaver, Katie England

Indiana Connected and Autonomous Vehicle Summit

No abstract provided.


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