Database Support and Modeling for the Mechanistic Empirical Pavement Design Guide (MEPDG)

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ISBN 13 :
Total Pages : 450 pages
Book Rating : 4.:/5 (472 download)

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Book Synopsis Database Support and Modeling for the Mechanistic Empirical Pavement Design Guide (MEPDG) by : Qiang Li

Download or read book Database Support and Modeling for the Mechanistic Empirical Pavement Design Guide (MEPDG) written by Qiang Li and published by . This book was released on 2009 with total page 450 pages. Available in PDF, EPUB and Kindle. Book excerpt:

TRC-0702, Database Support for the Mechanistic-Empirical Pavement Design Guide (MEPDG)

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ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (456 download)

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Book Synopsis TRC-0702, Database Support for the Mechanistic-Empirical Pavement Design Guide (MEPDG) by : Kelvin C. P. Wang

Download or read book TRC-0702, Database Support for the Mechanistic-Empirical Pavement Design Guide (MEPDG) written by Kelvin C. P. Wang and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Mechanistic-empirical Pavement Design Guide

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Publisher : AASHTO
ISBN 13 : 156051423X
Total Pages : 218 pages
Book Rating : 4.5/5 (65 download)

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Book Synopsis Mechanistic-empirical Pavement Design Guide by : American Association of State Highway and Transportation Officials

Download or read book Mechanistic-empirical Pavement Design Guide written by American Association of State Highway and Transportation Officials and published by AASHTO. This book was released on 2008 with total page 218 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Guide for the Local Calibration of the Mechanistic-empirical Pavement Design Guide

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Publisher : AASHTO
ISBN 13 : 1560514493
Total Pages : 202 pages
Book Rating : 4.5/5 (65 download)

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Book Synopsis Guide for the Local Calibration of the Mechanistic-empirical Pavement Design Guide by :

Download or read book Guide for the Local Calibration of the Mechanistic-empirical Pavement Design Guide written by and published by AASHTO. This book was released on 2010 with total page 202 pages. Available in PDF, EPUB and Kindle. Book excerpt: This guide provides guidance to calibrate the Mechanistic-Empirical Pavement Design Guide (MEPDG) software to local conditions, policies, and materials. It provides the highway community with a state-of-the-practice tool for the design of new and rehabilitated pavement structures, based on mechanistic-empirical (M-E) principles. The design procedure calculates pavement responses (stresses, strains, and deflections) and uses those responses to compute incremental damage over time. The procedure empirically relates the cumulative damage to observed pavement distresses.

Local Calibration of Mechanistic Empirical Pavement Design Guide for North Eastern United States

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ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (775 download)

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Book Synopsis Local Calibration of Mechanistic Empirical Pavement Design Guide for North Eastern United States by : Shariq A. Momin

Download or read book Local Calibration of Mechanistic Empirical Pavement Design Guide for North Eastern United States written by Shariq A. Momin and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Mechanistic-Empirical Pavement Design Guide (MEPDG) developed under the National Cooperative Highway Research Program (NCHRP) 1-37A project is based on mechanistic-empirical analysis of the pavement structure to predict the performance of the pavement under different sets of conditions (traffic, structure and environment). MEPDG takes into account the advanced modeling concepts and pavement performance models in performing the analysis and design of pavement. The mechanistic part of the design concept relies on the application of engineering mechanics to calculate stresses, strains and deformations in the pavement structure induced by the vehicle loads. The empirical part of the concept is based on laboratory developed performance models that are calibrated with the observed distresses in the in-service pavements with known structural properties, traffic loadings, and performances. These models in the MEPDG were calibrated using a national database of pavement performance data (Long Term Pavement Performance, LTPP) and will provide design solution for pavements with a national average performance. In order to improve the performance prediction of the models and the efficiency of the design for a given state, it is necessary to calibrate it to local conditions by taking into consideration locally available materials, traffic information and the environmental conditions. The objective of this study was to calibrate the MEPDG flexible pavement performance models to local conditions of Northeastern region of United States. To achieve this, seventeen pavement sections were selected for the calibration process and the relevant data (structural, traffic, climatic and pavement performance) was obtained from the LTPP database. MEPDG software (Version 1.1) simulation runs were made using the nationally calibrated coefficients and the MEPDG predicted distresses were compared with the LTPP measured distresses (rutting, alligator and longitudinal cracking, thermal cracking and IRI). The predicted distresses showed fair agreement with the measured distresses but still significant differences were found. The difference between the measured and the predicted distresses were minimized through recalibration of the MEPDG distress models. For the permanent deformation models of each layer, a simple linear regression with no intercept was performed and a new set of model coefficients (ßr1, ßGB, and ßSG) for asphalt concrete, granular base and subgrade layer models were calculated. The calibration of alligator (bottom-up fatigue cracking) and longitudinal (topdown fatigue cracking) was done by deriving the appropriate model coefficients (C1, C2, and C4) since the fatigue damage is given in MEDPG software output. Thermal cracking model was not calibrated since the measured transverse cracking data in the LTPP database did not increase with time, as expected to increase with time. The calibration of IRI model was done by computing the model coefficients (C1, C2, C3, and C4) based on other distresses (rutting, total fatigue cracking, and transverse cracking) by performing a simple linear regression.

Mechanistic-empirical Pavement Design Guide Implementation Plan

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ISBN 13 :
Total Pages : 324 pages
Book Rating : 4.3/5 (555 download)

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Book Synopsis Mechanistic-empirical Pavement Design Guide Implementation Plan by : Todd E. Hoerner

Download or read book Mechanistic-empirical Pavement Design Guide Implementation Plan written by Todd E. Hoerner and published by . This book was released on 2007 with total page 324 pages. Available in PDF, EPUB and Kindle. Book excerpt: As AASH is expected to eventually adopt the MEPDG at its primary pavement design method, it is critical that the SDDOT become familiar with the MEPGD documentation and associated design software. The research conducted under this project was a first step toward achieving this goal.

Nchrp Synthesis 401

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Publisher : Transportation Research Board
ISBN 13 :
Total Pages : 154 pages
Book Rating : 4./5 ( download)

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Book Synopsis Nchrp Synthesis 401 by :

Download or read book Nchrp Synthesis 401 written by and published by Transportation Research Board. This book was released on with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Changes to the "Mechanistic-empirical Pavement Design Guide" Software Through Version 0.900, July 2006

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ISBN 13 :
Total Pages : 28 pages
Book Rating : 4.3/5 (91 download)

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Book Synopsis Changes to the "Mechanistic-empirical Pavement Design Guide" Software Through Version 0.900, July 2006 by :

Download or read book Changes to the "Mechanistic-empirical Pavement Design Guide" Software Through Version 0.900, July 2006 written by and published by . This book was released on 2006 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: "This digest summarizes key findings from NCHRP Project 1-40D, "Technical Assistance to NCHRP and NCHRP Project 1-40A: Versions 0.900 and 1.0 of the M-E Pavement Design Sofware," conducted by Applied Research Associates, Inc., and Arizona State University. The digest was prepared by Michael I. Darter ... [et al.]"--P. [1].

Analytical Methods in Petroleum Upstream Applications

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Publisher : CRC Press
ISBN 13 : 1138001481
Total Pages : 2054 pages
Book Rating : 4.1/5 (38 download)

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Book Synopsis Analytical Methods in Petroleum Upstream Applications by : Cesar Ovalles

Download or read book Analytical Methods in Petroleum Upstream Applications written by Cesar Ovalles and published by CRC Press. This book was released on 2015-04-02 with total page 2054 pages. Available in PDF, EPUB and Kindle. Book excerpt: Effective measurement of the composition and properties of petroleum is essential for its exploration, production, and refining; however, new technologies and methodologies are not adequately documented in much of the current literature. Analytical Methods in Petroleum Upstream Applications explores advances in the analytical methods and instrumentation that allow more accurate determination of the components, classes of compounds, properties, and features of petroleum and its fractions. Recognized experts explore a host of topics, including: A petroleum molecular composition continuity model as a context for other analytical measurements A modern modular sampling system for use in the lab or the process area to collect and control samples for subsequent analysis The importance of oil-in-water measurements and monitoring The chemical and physical properties of heavy oils, their fractions, and products from their upgrading Analytical measurements using gas chromatography and nuclear magnetic resonance (NMR) applications Asphaltene and heavy ends analysis Chemometrics and modeling approaches for understanding petroleum composition and properties to improve upstream, midstream, and downstream operations Due to the renaissance of gas and oil production in North America, interest has grown in analytical methods for a wide range of applications. The understanding provided in this text is designed to help chemists, geologists, and chemical and petroleum engineers make more accurate estimates of the crude value to specific refinery configurations, providing insight into optimum development and extraction schemes.

Evaluation of LTPP Climatic Data for Use in Mechanistic-Empirical Pavement Design Guide (MEPDG) Calibration and Other Pavement Analysis

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ISBN 13 :
Total Pages : 142 pages
Book Rating : 4.:/5 (915 download)

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Book Synopsis Evaluation of LTPP Climatic Data for Use in Mechanistic-Empirical Pavement Design Guide (MEPDG) Calibration and Other Pavement Analysis by : Charles Warren Schwartz

Download or read book Evaluation of LTPP Climatic Data for Use in Mechanistic-Empirical Pavement Design Guide (MEPDG) Calibration and Other Pavement Analysis written by Charles Warren Schwartz and published by . This book was released on 2015 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Analysis of the Mechanistic-empirical Pavement Design Guide Performance Predictions

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ISBN 13 :
Total Pages : 44 pages
Book Rating : 4.:/5 (662 download)

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Book Synopsis Analysis of the Mechanistic-empirical Pavement Design Guide Performance Predictions by : Stacey D. Diefenderfer

Download or read book Analysis of the Mechanistic-empirical Pavement Design Guide Performance Predictions written by Stacey D. Diefenderfer and published by . This book was released on 2010 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Guide for Mechanistic-Empirical Design of New and Rehabilitated Pavement Structures (MEPDG) is an improved methodology for pavement design and the evaluation of paving materials. The Virginia Department of Transportation (VDOT) is expecting to transition to using the MEPDG methodology in the near future. The purpose of this research was to support this implementation effort. A catalog of mixture properties from 11 asphalt mixtures (3 surface mixtures, 4 intermediate mixtures, and 4 base mixtures) was compiled along with the associated asphalt binder properties to provide input values. The predicted fatigue and rutting distresses were used to evaluate the sensitivity of the MEPDG software to differences in the mixture properties and to assess the future needs for implementation of the MEPDG. Two pavement sections were modeled: one on a primary roadway and one on an interstate roadway. The MEPDG was used with the default calibration factors. Pavement distress data were compiled for the interstate and primary route corresponding to the modeled sections and were compared to the MEPDG-predicted distresses. Predicted distress quantities for fatigue cracking and rutting were compared to the calculated distress model predictive errors to determine if there were significant differences between material property input levels. There were differences between all rutting and fatigue predictions using Level 1, 2, and 3 asphalt material inputs, although not statistically significant. Various combinations of Level 3 inputs showed expected trends in rutting predictions when increased binder grades were used, but the differences were not statistically significant when the calibration model error was considered. Pavement condition data indicated that fatigue distress predictions were approximately comparable to the pavement condition data for the interstate pavement structure, but fatigue was over-predicted for the primary route structure. Fatigue model predictive errors were greater than the distress predictions for all predictions. Based on the findings of this study, further refinement or calibration of the predictive models is necessary before the benefits associated with their use can be realized. A local calibration process should be performed to provide calibration and verification of the predictive models so that they may accurately predict the conditions of Virginia roadways. Until then, implementation using Level 3 inputs is recommended. If the models are modified, additional evaluation will be necessary to determine if the other recommendations of this study are impacted. Further studies should be performed using Level 1 and Level 2 input properties of additional asphalt mixtures to validate the trends seen in the Level 3 input predictions and isolate the effects of binder grade changes on the predicted distresses. Further, additional asphalt mixture and binder properties should be collected to populate fully a catalog for VDOT's future implementation use. The implementation of these recommendations and use of the MEPDG are expected to provide VDOT with a more efficient and effective means for pavement design and analysis. The use of optimal pavement designs will provide economic benefits in terms of initial construction and lifetime maintenance costs.

Enhancement and Local Calibration of Mechanistic-empirical Pavement Design Guide

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Publisher :
ISBN 13 :
Total Pages : 152 pages
Book Rating : 4.:/5 (111 download)

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Book Synopsis Enhancement and Local Calibration of Mechanistic-empirical Pavement Design Guide by : Hongren Gong

Download or read book Enhancement and Local Calibration of Mechanistic-empirical Pavement Design Guide written by Hongren Gong and published by . This book was released on 2018 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Mechanistic-Empirical Pavement Design Guide (MEPDG) represents the state-of-art procedure for pavement design. However, after more than a decade since its publication, the number of agencies that have reported entirely adopting this design system is small. Among the many causes of this phenomenon, the poor predictive accuracy of the performance prediction models is considered the most crucial one. To improve the accuracy of performance predicted by the MEPDG, a preliminary calibration was first conducted for these models with data from the pavement management system (PMS) of Tennessee, and then employed various machine learning algorithms for further improvements. Also, an approach for estimating the modulus of existing asphalt pavement was proposed to enhance the reliability of rehabilitation analysis with the MEPDG. The transfer functions for alligator cracking and longitudinal cracking were validated and calibrated with data collected from the PMS of the state of Tennessee. The results of calibration efforts showed that after calibration, both the bias and variance of the prediction were significantly reduced. It was noted that although local calibration helped improve the accuracy of the transfer functions, the extent of improvement is limited. An observation of the performance models revealed that they were either inadequately formulated or too inflexible to capture sufficient information from the inputs. To further improve the predictive performance of the transfer functions in the MEPDG, several machine learning algorithms were employed including the gradient boosted model (GBM) for fatigue cracking, deep neural networks for rutting, and random forest for IRI. Using the determination of coefficient (R2) and root mean squared error (RMSE) as the measure of model performance, compared with the global transfer functions, the models developed achieved significantly better predictive performance. The results from the regularized regression model indicated that, compared with the model using deflection basins parameters (DBPs), the one without DBPs could still generate modulus prediction of reasonable accuracy. Rehabilitation analyses in the MEPDG with the estimated modulus also contributed to the improved accuracy in pavement performance prediction.

Mechanistic-empirical Pavement Design Guide

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Publisher :
ISBN 13 : 9781560517702
Total Pages : 26 pages
Book Rating : 4.5/5 (177 download)

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Book Synopsis Mechanistic-empirical Pavement Design Guide by :

Download or read book Mechanistic-empirical Pavement Design Guide written by and published by . This book was released on 2021 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: This addendum provides the additions and revisions to 3rd edition of the MEPDG, including methods and inputs to the fracture-based top-down cracking model.

Risk Analysis and Reliabilty Improvement of Mechanistic-empirical Pavement Design

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ISBN 13 : 9781267549495
Total Pages : 544 pages
Book Rating : 4.5/5 (494 download)

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Book Synopsis Risk Analysis and Reliabilty Improvement of Mechanistic-empirical Pavement Design by : Danny Xingqiang Xiao

Download or read book Risk Analysis and Reliabilty Improvement of Mechanistic-empirical Pavement Design written by Danny Xingqiang Xiao and published by . This book was released on 2012 with total page 544 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reliability used in the Mechanistic Empirical Pavement Design Guide (MEPDG) is a congregated indicator defined as the probability that each of the key distress types and smoothness will be less than a selected critical level over the design period. For such a complex system as the MEPDG which does not have closed-form design equations, classic reliability methods are not applicable. A robust reliability analysis can rely on Monte Carlo Simulation (MCS). The ultimate goal of this study was to improve the reliability model of the MEPDG using surrogate modeling techniques and Monte Carlo simulation. To achieve this goal, four tasks were accomplished in this research. First, local calibration using 38 pavement sections was completed to reduce the system bias and dispersion of the nationally calibrated MEPDG. Second, uncertainty and risk in the MEPDG were identified using Hierarchical Holographic Modeling (HHM). To determine the critical factors affecting pavement performance, this study applied not only the traditional sensitivity analysis method but also the risk assessment method using the Analytic Hierarchy Process (AHP). Third, response surface models were built to provide a rapid solution of distress prediction for alligator cracking, rutting and smoothness. Fourth, a new reliability model based on Monte Carlo Simulation was proposed. Using surrogate models, 10,000 Monte Carlo simulations were calculated in minutes to develop the output ensemble, on which the predicted distresses at any reliability level were readily available. The method including all data and algorithms was packed in a user friendly software tool named ReliME. Comparison between the AASHTO 1993 Guide, the MEPDG and ReliME was presented in three case studies. It was found that the smoothness model in MEPDG had an extremely high level of variation. The product from this study was a consistent reliability model specific to local conditions, construction practices and specifications. This framework also presented the feasibility of adopting Monte Carlo Simulation for reliability analysis in future mechanistic empirical pavement design software.

Independent Review of the "Mechanistic-empirical Pavement Design Guide" and Software

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ISBN 13 :
Total Pages : 40 pages
Book Rating : 4.3/5 (91 download)

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Book Synopsis Independent Review of the "Mechanistic-empirical Pavement Design Guide" and Software by :

Download or read book Independent Review of the "Mechanistic-empirical Pavement Design Guide" and Software written by and published by . This book was released on 2006 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt: "This digest summarizes key findings from NCHRP Project 1-40A ... Part I ... was prepared by Stephen F. Brown, Scott Wilson Pavement Engineering, Ltd.; Part II was prepared by Michael M. Darter .... Applied Research Associates, Inc. ... [et al.]"--P. [1].

Evaluation of Long-term Pavement Performance (LTTP) Climatic Data for Use in Mechanistic-empirical Pavement Design Guide(MEPDG) Calibration and Other Pavement Analysis

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ISBN 13 :
Total Pages : 126 pages
Book Rating : 4.:/5 (911 download)

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Book Synopsis Evaluation of Long-term Pavement Performance (LTTP) Climatic Data for Use in Mechanistic-empirical Pavement Design Guide(MEPDG) Calibration and Other Pavement Analysis by :

Download or read book Evaluation of Long-term Pavement Performance (LTTP) Climatic Data for Use in Mechanistic-empirical Pavement Design Guide(MEPDG) Calibration and Other Pavement Analysis written by and published by . This book was released on 2015 with total page 126 pages. Available in PDF, EPUB and Kindle. Book excerpt: Improvements in the Long-Term Pavement Performance (LTPP) Program's climate data are needed to support current and future research into climate effects on pavement materials, design, and performance. The calibration and enhancement of the Mechanistic-Empirical Pavement Design Guide (MEPDG) is just one example of these emerging needs. A newly emerging climate data source, the Modern-Era Retrospective Analysis for Research and Applications (MERRA), developed by the National Aeronautics and Space Administration (NASA) for its own in-house modeling needs, provides continuous hourly weather data starting in 1979 on a relatively fine-grained uniform grid. MERRA is based on a reanalysis model that combines computed model fields (e.g., atmospheric temperatures) with ground-, ocean-, atmospheric-, and satellite-based observations that are distributed irregularly in space and time. MERRA data are available at an hourly temporal resolution and 0.5 degrees latitude by 0.67 degrees longitude (approximately 31.1 by 37.30 mi at mid-latitudes) spatial resolution over the entire globe. MERRA data were compared against the best available ground-based observations both statistically and in terms of effects on pavement performance as predicted using the MEPDG. These analyses included a systematic quantitative evaluation of the sensitivity of MEPDG performance predictions to variations in fundamental climate parameters. More extensive analysis of MERRA data included additional statistical analysis comparing operating weather station (OWS) and MERRA data, evaluation of the correctness of MEPDG surface shortwave radiation (SSR) calculations and comparison of MEPDG pavement performance predictions using OWS and MERRA climate data for more sections. The principal conclusion from these evaluations was that the MERRA climate data were as good and in many cases substantially better than equivalent ground-based OWS data. Given these many benefits and very few if any significant limitations, MERRA is strongly recommended as the new future source for climate data in LTPP. Recommendations are provided for incorporating hourly MERRA data into the LTPP database.

Calibrating Mechanistic-Empirical Design Guide Permanent Deformation Models Based on Accelerated Pavement Testing

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ISBN 13 :
Total Pages : 9 pages
Book Rating : 4.:/5 (125 download)

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Book Synopsis Calibrating Mechanistic-Empirical Design Guide Permanent Deformation Models Based on Accelerated Pavement Testing by : Feng Hong

Download or read book Calibrating Mechanistic-Empirical Design Guide Permanent Deformation Models Based on Accelerated Pavement Testing written by Feng Hong and published by . This book was released on 2009 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: One of the challenges to the implementation of the mechanistic-empirical pavement design guide (MEPDG) comes from calibrating the transfer functions. This paper focuses on calibration of one of the major distress models in flexible pavement: permanent deformation or rutting. Two key aspects are critical to a successful rutting model calibration: data and method. Regarding the data, existing in-field information only provides total rut depth, which could not meet the requirement of permanent deformation in each structural layer by the MEPDG. Concerning the method, existing work either fails to address calibration factors from a holistic perspective by only focusing on individual sections separately or ignores variability inherent in those factors. In this study, layer-wise permanent deformation from instrumented pavement under accelerated pavement testing serves to accommodate the models calibration. A systematic calibration procedure is established, which globally optimizes all available information across all test sections. Through simulation and numerical optimization, optimal calibration shift factors for three typical flexible pavement materials, asphalt mixture, unbound granular base, and finegrain soil are obtained as 0.60, 0.49, and 0.84, respectively. This implies that the uncalibrated MEPDG is biased toward overprediction of rut depth. It is further suggested that a more rational result for each calibrated factor is to introduce an appropriate distribution to characterize its uncaptured variability. In addition, a case study involving using calibrated MEPDG to predict pavement performance or life indicates that (1) model calibration has a significant impact on the prediction and (2) the "fourth power law" is supported by the MEPDG.