PMSS Project Details

Project ID:	FHWA-PROJ-07-0017
Project Name:	Improved Reliability Modeling and Analysis for Primary Pavement Distress Models of Mechanistic-Empirical Design Guide
Status:	Completed
Contact:	Last Name: Sivaneswaran First Name: Nadarajah (Siva) Telephone: 202-493-3147 E-mail: nadarajah.sivaneswaran@dot.gov
Organization:	Federal Highway Administration - Turner-Fairbank Highway Research Center (TFHRC)
Office:	Office of Infrastructure Research and Development
Team:	Pavement Design and Construction Team
Roadmap/Focus area(s):	Infrastructure Research and Technology Strategic Plan and Roadmap
Project Findings:	The research findings have been presented in three peer-reviewed journal papers. The research developed an efficient reliability procedure applicable to the NCHRP 1-37A Mechanistic-Empirical Pavement Design Guide and statistical analysis procedures for the identification of critical project specific input parameters.
Project Description:	This study is concerned with enhancing the reliability analysis currently used in the Mechanistic-Empirical Pavement Design Guide. The Mechanistic-Empirical Pavement Design Guide uses a set of mechanistic-empirical models to analyze distresses of pavement structures in response to traffic, climate, and materials. These models include transverse joint faulting and transverse cracking for rigid pavements, and permanent deformation, fatigue cracking, and thermal cracking for flexible pavements. In order to evaluate the reliability of a selected pavement structure, the current procedure utilizes the overall standard deviation of the measured distresses obtained from calibration against distressed pavements in comparison with predicted values. This technique is fairly simple; however, it is far from accurate. Some limitations of the method may be attributed to the standard deviation being calibration-site specific, as well as the assumption of normality of the distribution of the measured distress levels. Additionally, this method relies on the variability of the measured output rather than on the variability/uncertainty of the input parameters that induce such variability in distress. The identification of an improved methodology for assessing design reliability is a top priority. In this study, the uncertainties in model input parameters (materials, climate, traffic) due to inherent spatial variability of materials and testing nonuniformity will be incorporated by using a number of advanced reliability techniques to assess the reliability of flexible and rigid pavements. Both analytical and simulation will be investigated. Materials variability and uncertainty associated with estimating many other input parameters will be determined from historical records. The reliability associated with pavement smoothness, as a primary measure of ride quality, in response to the various distresses encountered will be analyzed. Design reliabilities obtained from the various methods used will be compared to the current method. Advantages and disadvantages of the new methodologies in comparison with the current method will be discussed in the light of both the accuracy and computational feasibility or practicality.
Laboratories:	Not Applicable
Start Date:	August 19, 2007
End Date:	March 28, 2009
Funding Amount:	$50,000.00
FHWA Program Name:	Innovative Pavement Research and Deployment
Goals:	The key project objectives are: 1.) Reliable and Effective Pavement Design, and 2.) Efficient Reliability Analysis for Pavement Design.
Project Type:	Onsite
Background Information:	Data not yet available
Test Methodology:	Numerical Analysis
Other Information:	Data not yet available
Partners:	Washington State University; Role(s): Technical
More Information URL(s):
Fieldtest:	Data not yet available
Expected Benefits:	The successful outcome will improve the reliability of Mechanistic-Empirical Pavement Design Guide predictions and address some of the shortcomings in the current approach.
Deliverables:	Name: Technical Papers Product Type(s): Other Description: Thyagarajan, S., Muhunthan, B., Sivaneswaran, N. and Petros, K. “Efficient Simulation Techniques for Reliability Analysis of Flexible Pavements Using the Mechanistic‐Empirical Pavement Design Guide”, accepted for publication in the Journal of Transportation Engineering, ASCE (published online on 12 March 2011) Thyagarajan, S., Sivaneswaran, N., Muhunthan, B. and Petros, K. “Statistical Analysis of Critical Input Parameters in Mechanistic Empirical Pavement Design Guide”, 85th Annual Meeting and Technical Sessions of the Association of Asphalt Paving Technologists, Sacramento, California, March 7-10, 2010 Audiences: Researchers, State highway agencies Secondary Audiences:
Related URL(s):
FHWA Topics:	Roads and Bridges--Pavement and Materials Research/Technologies--FHWA Research and Technology Research/Technologies--Turner-Fairbank Highway Research Center (TFHRC)
TRT Terms:	PAVEMENT DESIGN MECHANISTRIC-EMPIRICAL PAVEMENT DESIGN PAVEMENT DESIGN RELIABILITY ANALYSIS
FHWA Disciplines:	Pavement and Materials
Subject Areas:	Pavements