2013 Session: 239

• Analysis of Impacts of Specimen Type on Dynamic Modulus and Predicted Pavement Performance
  Abstract: This study focused on determining the impacts of specimen type on dynamic modulus and flexible pavement predicted performance. Mixtures that were evaluated included both commonly-used dense-graded asphalt and those modified with emerging technologies. Dynamic modulus (|E*|) data was measured with two different test methods (IDT and Uniaxial Compression) and then analyzed using prediction tools (Mechanistic Empirical Pavement Design Guide (MEPDG) software, Quality Related Specification Software (QRSS), and the Asphalt Mixture Performance Tester (AMPT) Quality Assurance (QA) Program). Pavement distresses that were predicted included rutting in the surface layer as well as fatigue cracking. Performance predictions based on |E*| data from laboratory reheated and compacted specimens were equivalent to those resulting from the plant-compacted and field-compacted specimens. The results suggested that it may not be necessary to require plant-compacted or field-compacted asphalt specimens. A comparison of the different analysis tools also suggested that the MEPDG can be used effectively with Level 2 inputs, in lieu of requiring Level 1 inputs, to predict the service life of flexible pavements. By performing a parametric analysis, it was established that the MEPDG-predicted distresses were reasonable and the MEPDG may prove an effective substitute for the QRSS software. The data supported that transportation agencies can choose their preferred test method and specimen type and expect similar performance based on the pavement distresses predicted. It was recommended that agencies should select their method based upon the type of pavement distress most likely to occur at the design location.
  Authors: Guercio, Maria Chiara; McCarthy, Leslie Ann; Bennert, Thomas A.; DeJarnette, Van
  Authors: Guercio, Maria Chiara; McCarthy, Leslie Ann; Bennert, Thomas A.; DeJarnette, Van
  Year: 2013
  Document Type: Paper
  Subject: Design; Pavements
  Session: 239
  Paper Number: 13-0724
• Field Performance Evaluation of Stone Interlayer Pavement in Louisiana
  Abstract: A conventional cement stabilized/treated or soil cement base (CSB) layer has been used extensively for non-interstate asphalt pavements in Louisiana to overcome problems caused by soft subgrade soil. However, due to the shrinkage in the CSB layer, cracking occurs in the base, and subsequently reflects through to the surface of the asphalt pavement. In order to reduce reflective cracking and improve the long-term performance of asphalt pavements in Louisiana, a stone interlayer between the CSB layer and the hot mix asphalt concrete (HMA) surface layer had been adopted. In this study, field performances of a stone interlayer pavement test section and cement stabilized base test control section on LA-97 in Acadia Parish, Louisiana, were monitored during 20 years of service. In addition, performances of other nine stone interlayer pavement sections in Louisiana constructed from 1999 to 2008 were monitored and evaluated. Field evaluations in this study included distress surveys on all 11 pavement sections, and nondestructive evaluation of pavement structure by the falling weight deflectometer (FWD) and the dynamic deflection determination system (Dynaflect) test on nine of those sections. The field evaluation results indicated that the stone interlayer test section on LA-97 had a superior pavement performance than the control section over the 20 years of service, and other nine stone interlayer pavement sections were in a very good pavement condition after 2.5 to 12 years of service.
  Authors: Chen, Xingwei; Zhang, Zhongjie; Lambert, Jeff
  Authors: Chen, Xingwei; Zhang, Zhongjie; Lambert, Jeff
  Year: 2013
  Document Type: Paper
  Subject: Design; Pavements
  Session: 239
  Paper Number: 13-1556
• Selection of Design Parameters for Construction of a Surrogate Model for the MEPDG
  Abstract: The American Association of State Highway and Transportation Officials’ (AASHTO) Mechanistic-Empirical Pavement Design Guide (MEPDG) is the most widely utilized M-E design procedure in the U.S. The MEPDG incorporates extensive climatic and empirical performance data. Inclusion of such extensive data hinders the computational efficiency of design with the MEPDG and likely includes design parameters of little significance to pavement performance. Construction of a surrogate model that emulates the behavior of the MEPDG can be utilized to reduce computational expense and is valuable in any situation where large numbers of evaluations are required. Development of a surrogate improves efficiency, but requires selection of a reduced quantity of design parameters compared to the MEPDG model that it is meant to emulate. This paper includes investigation of the required quantity of input parameters necessary to accurately imitate the MEPDG design procedure. This investigation will provide a tool for sensitivity analysis for the MEPDG. The objective of this paper is to develop a variable selection process for sensitivity analysis and construction of a surrogate model for the Level 1 MEPDG design procedure utilizing the DARWin-ME design software. Investigation of the importance of input variables is investigated for 3 distinct climate regions to examine the impact of climatic data on the relative significance of input variables. Sensitivity analysis will provide insight to the most significant design information for Level 1 analyses. Further, construction and verification of a surrogate model for a Level 1 MEPDG analysis incorporating the information obtained from the selection process is presented.
  Authors: Retherford, Jennifer Q; McDonald, Mark
  Authors: Retherford, Jennifer Q; McDonald, Mark
  Year: 2013
  Document Type: Paper
  Subject: Design; Pavements
  Session: 239
  Paper Number: 13-2623
• Use of Precipitation Records in Drainage Design of Porous Asphalt Surface Layer
  Abstract: Precipitation, including rain and snow, in general has a negative effect on road system efficiency and safety. Porous asphalt (PA) layer, with its high permeability and its capacity to drain water from the surface, can largely mitigate this impact. The performance of PA surface layer should meet drainage requirements that depend on the local weather type and design targets of safety/efficiency levels. This paper proposed a method for incorporating local weather records into PA layer design. As hydrologic constructions are based on intensity duration frequency (IDF) curves, this paper discusses the use of the same method for designing PA layers. As the exposure time of pavement to wet weather may be more directly related to road accidents and efficiency, the method of wet exposure is introduced as well. An IDF versus wet exposure plot shows these two parameters are not correlated; thus the two parameters cannot be used interchangeably.The IDF curves were developed based on extreme weather experienced across a number of years. However, no evidence shows the extreme weather is the prevalent concern of pavement design. The design based on IDF criteria leads to a low invest/outcome ratio. For pavement, the total time of exposure to adverse precipitation appears to be more important. The wet exposure method can be improved to provide exposure times for the different designs and fulfill PA thickness design requirements based on local weather and safety/efficiency expectation.
  Authors: Tang, Lijie; Flintsch, Gerardo W.
  Authors: Tang, Lijie; Flintsch, Gerardo W.
  Year: 2013
  Document Type: Paper
  Subject: Design; Pavements
  Session: 239
  Paper Number: 13-2720
• Mechanistic-Empirical Pavement Design to Mitigate Rutting in Asphalt Overlays of Concrete Pavements Using MEPDG and CalME
  Abstract: This paper describes the development of an approach for the prediction of rutting of newly constructed composite pavements and asphalt overlays of existing concrete pavements (AC-PCC). It investigates the MEPDG rutting model and the CalME procedure being developed by Caltrans and the University of California Pavement Research Center (UCPRC) and introduces a procedure incorporating the CalME rutting model into the MEPDG framework. The overall goal was to provide a procedure for rutting in AC-PCC design and analysis for pavement engineers that does not require uncommon inputs and does not force the user outside of the MEPDG framework. The article also describes the validation of the developed procedure using experimental data from the UCPRC and from the Minnesota Road Research facility (MnROAD); in addition the article details a brief sensitivity analysis of the developed procedure for rutting in AC-PCC. It is hoped that the developed procedure represents a step forward for the design and analysis of AC-PCC using the MEPDG.
  Authors: Khazanovich, Lev; Tompkins, Derek; Saxena, Priyam; Wu, Rongzong; Harvey, John
  Authors: Khazanovich, Lev; Tompkins, Derek; Saxena, Priyam; Wu, Rongzong; Harvey, John
  Year: 2013
  Document Type: Paper
  Subject: Design; Pavements
  Session: 239
  Paper Number: 13-3258
• Use of Monte Carlo Filtering Method for Regional Sensitivity Analysis of DARWin-ME
  Abstract: Since AASHTO released the Mechanistic-Empirical Pavement Design Guide (MEPDG) for public review in 2004, many highway research agencies have performed sensitivity analyses using the prototype MEPDG design software. The information provided by the sensitivity analysis is essential for design engineers to better understand the MEPDG design model and to identify important input parameters for pavement design. In the past, both local and global sensitivity analyses have been carried out. Meanwhile, different sensitivity indices have been proposed for ranking the importance of the input parameters. However, both local and global sensitivity analyses have their limitations. In this paper, a regional sensitivity analysis method, Monte Carlo filtering (MCF), is presented. The MCF method maintains many advantages of the global sensitivity analysis, while focusing on the regional sensitivity of the MEPDG model near the design criteria rather than the entire problem domain. It was shown the information obtained from the MCF method is more helpful and accurate in guiding design engineers in pavement design practices. To demonstrate the methodology, a typical three-layer flexible pavement structure was used as an example. A detailed procedure to generate Monte Carlo runs using the new DARWin-ME software was provided. Based on the example, the strengths, practical issues, and applications of the MCF method are also discussed.
  Authors: Yang, Xiaoming; Wu, Zhong
  Authors: Yang, Xiaoming; Wu, Zhong
  Year: 2013
  Document Type: Paper
  Subject: Design; Pavements
  Session: 239
  Paper Number: 13-3842
• Evaluation of Long-Lasting Perpetual Asphalt Pavement Using Life-Cycle Cost Analysis
  Abstract: In 2006, the Oklahoma Department of Transportation (OKDOT) sponsored work at the National Center for Asphalt Technology (NCAT) Pavement Test Track to compare the performance of two sections that were designed to determine the thickness required to obtain a perpetual pavement. One section (Section N9) was designed to be a perpetual pavement (14 inches thick) and the thickness of the other section was reduced to 10 inches (based on AASHTO 1993 design guide) to see how well it performed and to help identify the thickness needed for a perpetual pavement. This paper presents a life-cycle cost analysis (LCCA) to quantify the benefits of building the perpetual pavement section compared to the long term cost of the thinner section. LCCA was conducted using RealCost 2.5, which is available through FHWA, to determine quantitative estimates of construction schedule, work zone user costs, and agency costs for initial construction and rehabilitation activities. The perpetual pavement section was found to have a lower life-cycle cost than the conventional pavement section and provide better service to highway users. Furthermore, to help better planning for future preservation study the estimated present serviceability rating (PSR) as a function of international roughness index (IRI) for two different designs (perpetual and non-perpetual) was carefully evaluated. The findings of surface measurements for both sections clearly demonstrate a difference between perpetual and conventional pavement serviceability for a given level of roughness and accumulated traffic. These results are also helpful to assess the improvement of conventional pavement after each rehabilitation treatments.
  Authors: Sakhaeifar, Maryam; Brown, E. Ray; Tran, Nam; Dean, Jeff
  Authors: Sakhaeifar, Maryam; Brown, E. Ray; Tran, Nam; Dean, Jeff
  Year: 2013
  Document Type: Paper
  Subject: Design; Pavements
  Session: 239
  Paper Number: 13-0330
  Practice-Ready: Yes
• Field Performance Evaluation of Stone Interlayer Pavement in Louisiana
  Authors: Chen, Xingwei
  Authors: Chen, Xingwei
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Design; Pavements
  Session: 239
  Paper Number: 13-1556
• Use of Precipitation Records in Drainage Design of Porous Asphalt Surface Layer
  Authors: Tang, Lijie
  Authors: Tang, Lijie
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Design; Pavements
  Session: 239
  Paper Number: 13-2720