Download or read book Improved Characterization of Truck Traffic Volumes and Axle Loads for Mechanistic empirical Pavement Design written by Ala R. Abbas and published by . This book was released on 2012 with total page 227 pages. Available in PDF, EPUB and Kindle. Book excerpt: The recently developed mechanistic-empirical pavement design guide (MEPDG) requires a multitude of traffic inputs to be defined for the design of pavement structures, including the initial two-way annual average daily truck traffic (AADTT), directional and lane distribution factors, vehicle class distribution, monthly adjustment factors, hourly truck distribution factors, traffic growth rate, axle load spectra by truck class (Class 4 to Class 13) and axle type (single, tandem, tridem, and quad), and number of axles per truck. Since it is not always practical to obtain site-specific traffic data, the MEPDG assimilates a hierarchal level concept that allows pavements to be designed using statewide averages and MEPDG default values without compromising the accuracy of the pavement design. In this study, a Visual Basic for Application (VBA) code was developed to analyze continuous traffic monitoring data and generate site-specific and statewide traffic inputs. The traffic monitoring data was collected by 143 permanent traffic monitoring sites (93 automated vehicle classifier (AVC) and 50 weigh-in-motion (WIM) sites) distributed throughout the State of Ohio from 2006 to 2011. The sensitivity of the MEPDG to the various traffic inputs was evaluated using two baseline pavement designs, one for a new flexible pavement and one for a new rigid pavement. Key performance parameters for the flexible pavement included longitudinal (top-down) fatigue cracking, alligator (bottom-up) fatigue cracking, transverse (low-temperature) cracking, rutting, and smoothness (expressed using IRI), while key performance parameters for the rigid pavement included transverse cracking (% slabs cracked), joint faulting, and smoothness. The sensitivity analysis results revealed that flexible pavements are moderately sensitive to AADTT, growth rate, vehicle class distribution, and axle load spectra; and not sensitive to hourly distribution factors, monthly adjustment factors, and number of axles per truck. Furthermore, it was found that rigid pavements are moderately sensitive to AADTT, growth rate, hourly distribution factors, vehicle class distribution, and axle load spectra; and not sensitive to monthly adjustment factors and number of axles per truck. Therefore, it is recommended to estimate the AADTT and the vehicle class distribution from site-specific short-term or continuous counts and obtain the truck growth rate from ODOT Modeling and Forecasting Section (Certified Traffic). As for the other traffic inputs, statewide averages can be used for the hourly distribution factors, axle load spectra, and number of axles per truck; and MEPDG defaults can be used for the monthly adjustment factors.
Download or read book Improved Characterization of Truck Traffic Volumes and Axle Loads for Mechanistic empirical Pavement Design written by Ala R. Abbas and published by . This book was released on 2012 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The recently developed mechanistic-empirical pavement design guide (MEPDG) requires a multitude of traffic inputs to be defined for the design of pavement structures, including the initial two-way annual average daily truck traffic (AADTT), directional and lane distribution factors, vehicle class distribution, monthly adjustment factors, hourly truck distribution factors, traffic growth rate, axle load spectra by truck class (Class 4 to Class 13) and axle type (single, tandem, tridem, and quad), and number of axles per truck. Since it is not always practical to obtain site-specific traffic data, the MEPDG assimilates a hierarchal level concept that allows pavements to be designed using statewide averages and MEPDG default values without compromising the accuracy of the pavement design. In this study, a Visual Basic for Application (VBA) code was developed to analyze continuous traffic monitoring data and generate site-specific and statewide traffic inputs. The traffic monitoring data was collected by 143 permanent traffic monitoring sites (93 automated vehicle classifier (AVC) and 50 weigh-in-motion (WIM) sites) distributed throughout the State of Ohio from 2006 to 2011. The sensitivity of the MEPDG to the various traffic inputs was evaluated using two baseline pavement designs, one for a new flexible pavement and one for a new rigid pavement. Key performance parameters for the flexible pavement included longitudinal (top-down) fatigue cracking, alligator (bottom-up) fatigue cracking, transverse (low-temperature) cracking, rutting, and smoothness (expressed using IRI), while key performance parameters for the rigid pavement included transverse cracking (% slabs cracked), joint faulting, and smoothness. The sensitivity analysis results revealed that flexible pavements are moderately sensitive to AADTT, growth rate, vehicle class distribution, and axle load spectra; and not sensitive to hourly distribution factors, monthly adjustment factors, and number of axles per truck. Furthermore, it was found that rigid pavements are moderately sensitive to AADTT, growth rate, hourly distribution factors, vehicle class distribution, and axle load spectra; and not sensitive to monthly adjustment factors and number of axles per truck. Therefore, it is recommended to estimate the AADTT and the vehicle class distribution from site-specific short-term or continuous counts and obtain the truck growth rate from ODOT Modeling and Forecasting Section (Certified Traffic). As for the other traffic inputs, statewide averages can be used for the hourly distribution factors, axle load spectra, and number of axles per truck; and MEPDG defaults can be used for the monthly adjustment factors.
Download or read book Analysis and Determination of Axle Load Spectra and Traffic Input for the Mechanistic Empirical Pavement Design Guide written by Yi Jiang and published by Purdue University Press. This book was released on 2008-03-01 with total page 110 pages. Available in PDF, EPUB and Kindle. Book excerpt: The values of equivalent single axle loads (ESAL) have been used to represent the vehicle loads in pavement design. To improve the pavement design procedures, a new method, called the Mechanistic-Empirical Pavement Design Guide (MEPDG), has been developed to use the axle load spectra to represent the vehicle loads in pavement design. These spectra represent the percentage of the total axle applications within each load interval for single, tandem, tridem, and quad axles. Using axle load spectra as the traffic input, the MEPDG method is able to analyze the impacts of varying traffic loads on pavement and provide an optimal pavement structure design. In addition, the new method can be used to analyze the effects of materials and the impacts of seasons, to compare rehabilitation strategies, and to perform forensic analyses of pavement conditions. The MEPDG utilizes mechanistic-empirical approaches to realistically characterize inservice pavements and allows the full integration of vehicular traffic loadings, climatic features, soil characteristics, and paving materials properties into the detailed analysis of pavement structural behaviors and the resulting pavement performance. In order to provide the traffic data input required by the MEPDG, the Indiana Department of Transportation (INDOT) made an effort to obtain truck traffic information from the traffic data collected through weigh-in-motion (WIM) stations. This study was conducted to create the truck traffic spectra and other traffic inputs for INDOT to implement the new pavement design method. Furthermore, the INDOT AADT data were used in this study to analyze the spatial distributions of the traffic volumes in Indiana and to obtain the spatial distributions of traffic volumes.
Download or read book Traffic Characterization for a Mechanistic empirical Pavement Design written by Jorge A. Prozzi and published by . This book was released on 2006 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt: The goal of this research study was to assess and address the implications of the axle load spectra approach proposed by the M-E Design Guide. In addition, recommendations were developed regarding traffic data needs and availability to aid in deciding the installation locations of future WIM stations in Texas. A methodology for specifying the required accuracy of WIM equipment based on the effect that this accuracy has on pavement performance prediction was also developed. Regarding traffic volume forecasting, a methodology is presented that allows optimum use of available data by simultaneously estimating traffic growth and seasonal traffic variability.
Download or read book Traffic Data Collection Analysis and Forecasting for Mechanistic Pavement Design written by Cambridge Systematics and published by Transportation Research Board. This book was released on 2005 with total page 127 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Truck Traffic and Load Spectra of Indiana Roadways for the Mechanistic Empirical Pavement Design Guide written by Jieyi Bao and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Mechanistic-Empirical Pavement Design Guide (MEPDG) has been employed for pavement design by the Indiana Department of Transportation (INDOT) since 2009 and has generated efficient pavement designs with a lower cost. It has been demonstrated that the success of MEPDG implementation depends largely on a high level of accuracy associated with the information supplied as design inputs. Vehicular traffic loading is one of the key factors that may cause not only pavement structural failures, such as fatigue cracking and rutting, but also functional surface distresses, including friction and smoothness. In particular, truck load spectra play a critical role in all aspects of the pavement structure design. Inaccurate traffic information will yield an incorrect estimate of pavement thickness, which can either make the pavement fail prematurely in the case of under-designed thickness or increase construction cost in the case of over-designed thickness. The primary objective of this study was to update the traffic design input module, and thus to improve the current INDOT pavement design procedures. Efforts were made to reclassify truck traffic categories to accurately account for the specific axle load spectra on two-lane roads with low truck traffic and interstate routes with very high truck traffic. The traffic input module was updated with the most recent data to better reflect the axle load spectra for pavement design. Vehicle platoons were analyzed to better understand the truck traffic characteristics. The unclassified vehicles by traffic recording devices were examined and analyzed to identify possible causes of the inaccurate data collection. Bus traffic in the Indiana urban areas was investigated to provide additional information for highway engineers with respect to city streets as well as highway sections passing through urban areas. New equivalent single axle load (ESAL) values were determined based on the updated traffic data. In addition, a truck traffic data repository and visualization model and a TABLEAU interactive visualization dashboard model were developed for easy access, view, storage, and analysis of MEPDG related traffic data.
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:
Download or read book Traffic Data Collection Analysis and Forecasting for Mechanistic Pavement Design written by National Cooperative Highway Research Program and published by . This book was released on 2004 with total page 238 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Review of the Virginia Department of Transportation s Truck Weight Data Plan for the Mechanistic empirical Pavement Design Guide written by Benjamin H. Cottrell and published by . This book was released on 2011 with total page 59 pages. Available in PDF, EPUB and Kindle. Book excerpt: In 2003, staff of the Virginia Transportation Research Council (now the Virginia Center for Transportation Innovation and Research) and the Virginia Department of Transportation (VDOT) developed a plan to collect traffic and truck-axle weight data to support the Guide for Mechanistic-Empirical Design of New and Rehabilitated Pavement Structures, known as the Mechanistic-Empirical Pavement Design Guide (MEPDG). The purpose of this study was to review VDOT's traffic data plan for the MEPDG and revise it as needed. The review included an assessment of the data obtained from the VDOT and Virginia Department of Motor Vehicles weigh-in-motion (WIM) sites and the appropriateness of the truck weight groups in VDOT's traffic data plan. Information on truck travel patterns and characteristics was compiled. There is very little literature that provides specific information on the structure of a traffic data plan for the MEPDG. Guidance provided by the Federal Highway Administration allows for much flexibility in the development of such a plan. Most states are working to develop the plan, and such plans that are already in place vary considerably. The Corridors of Statewide Significance in Virginia's statewide long-range multimodal transportation plan represent the routes where truck traffic is most prominent and therefore represent routes on which the VDOT plan should focus. The study recommends that VDOT continue with its current truck weight data plan for the MEPDG. With this plan, VDOT is positioned to implement the MEPDG from a truck data perspective, The WIM data comprise an important input to the MEPDG process that is expected to provide VDOT with more accurate pavement designs based on actual traffic loadings in Virginia.
Download or read book The Effects of Truck Volume Mix and Weight Distribution on Pavement Design written by David A. Friedrichs and published by . This book was released on 1988 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Characterization of Truck Traffic in Michigan for the New Mechanistic Empirical Pavement Design Guide written by Joel Thomas Brown and published by . This book was released on 2009 with total page 410 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Advances in Materials and Pavement Performance Prediction II written by K. Anupam and published by CRC Press. This book was released on 2020-12-08 with total page 501 pages. Available in PDF, EPUB and Kindle. Book excerpt: Inspired from the legacy of the previous four 3DFEM conferences held in Delft and Athens as well as the successful 2018 AM3P conference held in Doha, the 2020 AM3P conference continues the pavement mechanics theme including pavement models, experimental methods to estimate model parameters, and their implementation in predicting pavement performance. The AM3P conference is organized by the Standing International Advisory Committee (SIAC), at the time of this publication chaired by Professors Tom Scarpas, Eyad Masad, and Amit Bhasin. Advances in Materials and Pavement Performance Prediction II includes over 111 papers presented at the 2020 AM3P Conference. The technical topics covered include: - rigid pavements - pavement geotechnics - statistical and data tools in pavement engineering - pavement structures - asphalt mixtures - asphalt binders The book will be invaluable to academics and engineers involved or interested in pavement engineering, pavement models, experimental methods to estimate model parameters, and their implementation in predicting pavement performance.
Download or read book MEPDG Traffic Loading Defaults Derived from Traffic Pooled Fund Study written by O.I. Selezneva and published by . This book was released on 2016 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt: As traffic loading inputs, the Mechanistic-Empirical Pavement Design Guide (MEPDG), Interim Edition: A Manual of Practice requires detailed axle loading information in the form of normalized acle load spectra (NALS), number of axle per truck class and axle group types, and axle spacing inputs. These data are obtained from weigh-in-motion (WIM) sites. The objective of this project was to evaluate the applicability of the existing MEPDG global traffic loading defaults and to use research-quality WIM data from the Long-Term Pacement Performance (LTPP) Specific Pavement Studies (SPS) Traffic Data Collection pooled fund study to revise and improve the global default axle loading values. This report provides an assessment, presents findings from the LTPP SPS traffic pooled fund study traffic data review, describes a methodology to generate new MEPDG traffic loading defaults, and provides a description of the new traffic loading defaults and recommendations for their use. The report also discusses a sensitivity analysis of MEPDG pavement performance models to NALS. Significant differences found in the MEPDG outcomes support the need for axle loading characterization beyond a simple default value for heavy trucks that dominate vehicle class distributions, especially for class 9 trucks. The effect of WIM accuracy on axle weight measurements, NALS estimates, and the associated MEPDG outcomes was also investigated. It was found that drift in WIM system calibration leading to over 5 percent bias in mean error between true and WIM-measured axle weight could lead to significant differences in MEPDG design outcomes. In addition, two new statistical parameters were developed in this study: (1) a summary statistic used to describe traffic loads for comparison and grouping of similar NALS called the relative pavement performance impact factor and (2) a parameter used to quantify errors associated with NALs and to assess NALS reliability called the pooled weighted load error.
Download or read book Analysis and Forecast of Truck Traffic Loads and the Relative Damage to Pavement Systems as a Function of Axle Configurations Final Report written by Shekhar Govind and published by . This book was released on 1987 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Methodology for Obtaining Traffic Data Input to the NCHRP 1 37A PDG written by Jingjuan Li and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Mechanistic Empirical Compatible Traffic Data Generation Portable Weigh in Motion Versus Cluster Analysis written by Lubinda F. Walubita and published by . This book was released on 2020 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt: Axle load distribution factors (ALDFs) are used as one of the primary traffic data inputs for mechanistic-empirical (ME) pavement design methods for predicting the impact of varying traffic loads on pavement performance with a higher degree of accuracy than empirical methods that are solely based on equivalent single axle load (ESAL) concept. Ideally, to ensure optimal pavement structural design, site-specific traffic load spectra data--generated from weigh-in-motion (WIM) systems--should be used during the pavement design process. However, because of the limited number of available permanent WIM stations (in Texas, for example), it is not feasible to generate a statewide ALDFs database for each highway or project from permanent WIM data. In this study, two possible alternative methods, namely, the direct measurement using a portable WIM system and the cluster analysis technique, were explored for generating site-specific ME-compatible traffic data for a highway test section, namely, state highway (SH) 7 in Bryan District (Texas). The traffic data were then used for estimating pavement performance using a ME pavement design software, namely, the Texas Mechanistic-Empirical Thickness Design System (TxME). The TxME-predicted pavement performance (e.g., rutting) using the portable WIM-generated traffic input parameters closely matched with the actual field performance. Overall, the study findings indicated that the portable WIM (with proper installation and calibration) constitutes an effective means for rapidly collecting reliable site-specific ME-compatible traffic data.
Download or read book Characterization and Development of Axle Load Spectra to Enhance Pavement Design and Performance on the Basis of New Mechanistic empirical Design Guide in Louisiana written by Bharath Kumar Sridhar and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
