Download or read book Sensitivity Analyses of Flexible Pavement Performance in VT NY and MA Using the Mechanistic Empirical Pavement Design Guide written by I. Mark Nogaj and published by . This book was released on 2011 with total page 840 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Sensitivity Analyses for Flexible Pavement Design with the Mechanistic Empirical Pavement Design Guide written by and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Sensitivity Analysis of Flexible Pavement Performance Parameters in the Mechanistic empirical Design Guide written by Armando Orobio and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
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.
Download or read book Sensitivity Analysis of Rigid Pavement Design Inputs Using Mechanistic empirical Pavement Design Guide written by Alper Guclu and published by . This book was released on 2005 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pavement design procedures, available in the literature, do not fully take advantage of mechanistic concepts, which make them heavily rely on empirical approaches. Because of the heavy dependence on empirical procedures, the existing design methodologies do not capture the actual behavior of Portland cement concrete (PCC) pavements. However, reliance on empirical solutions can be reduced by introducing mechanistic-empirical methods, which is now adopted in the newly released mechanistic-empirical pavement design guide (MEPDG). This new design procedure incorporates a wide range of input parameters associated with the mechanics of rigid pavements. To compare the sensitivity of these various input parameters on the performance of concrete pavements, two jointed plain concrete pavement (JPCP) sites were selected in Iowa. These two sections are also part of the Long Term Pavement Performance (LTPP) program where a long history of pavement performance data exists. Data obtained from the Iowa Department of Transportation (Iowa DOT) Pavement Management Information System (PMIS) and LTPP database were used to form two standard pavement sections for the comprehensive sensitivity analyses. The sensitivity analyses were conducted using the MEPDG software to study the effects of design input parameters on pavement performance of faulting, transverse cracking, and smoothness. Based on the sensitivity results, ranking of the rigid pavement input parameters were established and categorized from most sensitive to insensitive to help pavement design engineers to identify the level of importance of each input parameter. The curl/warp effective temperature difference (built-in curling and warping of the slabs) and PCC thermal properties are found to be the most sensitive input parameters. Based on the comprehensive sensitivity analyses, the idea of developing an expert system was introduced to help the pavement design engineers identify the input parameters that they can modify to satisfy the predetermined pavement performance criteria. Predicted pavement distresses using the MEPDG software for the two Iowa rigid pavement sites were compared against the measured pavement distresses obtained from the Iowa DOT's PMIS and comparison results are discussed in this study.
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.
Download or read book Mechanistic empirical Pavement Design Guide Flexible Pavement Performance Prediction Models for Montana Reference manual written by Harold L. Von Quintus and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Mechanistic empirical Pavement Design Guide Flexible Pavement Performance Prediction Models for Montana written by James S. Moulthrop and published by . This book was released on 2007 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Preparation of the Implementation Plan of AASHTO Mechanistic empirical Pavement Design Guide M EPDG in Connecticut written by Iliya Yut and published by . This book was released on 2017 with total page 133 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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.
Download or read book Improvements to Strain Computation and Reliabilty Analysis of Flexible Pavements in the Mechanistic empirical Pavement Design Guide written by Senthilmurugan Thyagarajan and published by . This book was released on 2009 with total page 179 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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.
Download or read book Verification of Mechanistic empirical Design Models for Flexible Pavements Through Accelerated Pavement Testing written by and published by . This book was released on 2014 with total page 178 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Midwest States Accelerated Pavement Testing Pooled Fund Program, financed by the highway departments of Kansas, Iowa, and Missouri, has supported an accelerated pavement testing (APT) project to validate several models incorporated in the NCHRP 1-37A design method, popularly known as Mechanistic-Empirical Pavement Design Guide (MEPDG) for flexible pavements. The following models were investigated: the dynamic modulus estimation model, the relationship between the dynamic modulus and the pavement response; and the relationship between the pavement response (strains) and pavement performance. In addition to these, the experiment aims to compare the performance of the coarse and fine Superpave mixes, and to validate and calibrate the Asphalt Pavement Analyzer (APA) and Hamburg Wheel-Tracking Device Tester as screening tools for estimating rutting performance of Superpave asphalt mixes. The experiments were conducted at the Civil Infrastructure Systems Laboratory at Kansas State University. The test program consisted of constructing 12 flexible pavement structures and subjecting them to full-scale accelerated loading tests. The experiment found that the revised Witczak model predicts the dynamic modulus of asphalt concrete mixes with reasonable accuracy. The MEPDG structural response model under-predicted the longitudinal strains at the bottom of the asphalt concrete layers, while the MEPDG over-predicted the permanent deformation in the asphalt layer. The comparison between the results of the laboratory rutting tests performed at 35 degrees Celsius indicate that results of the Hamburg Wheel Rut Test correlate best with results of the APT experiment, followed by those from the APA.
Download or read book Sensitivity Analysis of Flexible Pavement Response and AASHTO 2002 Design Guide for Properties of Unbound Layers written by Sanaa Masad and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Unbound granular materials are generally used in road pavements as base and subbase layers. The granular materials provide load distribution through aggregate contacts to a level that can help the subgrade to withstand the applied loads. Several research studies have shown that unbound pavement layers exhibit anisotropic properties. Anisotropy is caused by the preferred orientation of aggregates and compaction forces. The result is unbound pavement layers that have higher stiffness in the vertical direction than in the horizontal direction. This behavior is not accounted for in the design and analysis procedures included in the proposed AASHTO 2002 design guide. One of the objectives of this study is to conduct a comparative analysis of flexible pavement response using different models for unbound pavement layers: linear isotropic, nonlinear isotropic, linear anisotropic and nonlinear anisotropic. Pavement response is computed using a finite element program. The computations from nonlinear isotropic and anisotropic models of unbound layers are compared to the AASHO field experimental measurements. The second objective is to analyze the influence of using isotropic and anisotropic properties for the pavement layers on the performance of flexible pavements calculated using the AASHTO 2002 models. Finally, a comprehensive sensitivity analysis of the proposed AASHTO 2002 performance models to the properties of the unbound pavement layers is conducted. The sensitivity analysis includes different types of base materials, base layer thicknesses, hot mix asphalt type and thickness, environmental conditions, and subgrade materials.
Download or read book Sensitivity Analysis and Calibration of the Alligator Cracking Model in the Mechanistic empirical Pavement Design Guide Using Regional Data written by Vivek Jha and published by . This book was released on 2009 with total page 202 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Management of Uncertainty for Flexible Pavement Design Utilizing Analytical and Probabilistic Methods written by Jennifer Queen Retherford and published by . This book was released on 2012 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt:
