Read Books Online and Download eBooks, EPub, PDF, Mobi, Kindle, Text Full Free.
Proposed Enhancements To Pavement Me Design Improved Consideration Of The Influence Of Subgrade And Unbound Layers On Pavement Performance
Download Proposed Enhancements To Pavement Me Design Improved Consideration Of The Influence Of Subgrade And Unbound Layers On Pavement Performance full books in PDF, epub, and Kindle. Read online Proposed Enhancements To Pavement Me Design Improved Consideration Of The Influence Of Subgrade And Unbound Layers On Pavement Performance ebook anywhere anytime directly on your device. Fast Download speed and no annoying ads. We cannot guarantee that every ebooks is available!
Book Synopsis Proposed Enhancements to Pavement ME Design: Improved Consideration of the Influence of Subgrade and Unbound Layers on Pavement Performance by :
Download or read book Proposed Enhancements to Pavement ME Design: Improved Consideration of the Influence of Subgrade and Unbound Layers on Pavement Performance written by and published by . This book was released on 2019 with total page 231 pages. Available in PDF, EPUB and Kindle. Book excerpt: The performance of flexible and rigid pavements is known to be closely related to properties of the base, subbase, and/or subgrade. However, some recent research studies indicate that the performance predicted by this methodology shows a low sensitivity to the properties of underlying layers and does not always reflect the extent of the anticipated effect/ So the procedures contained in the American Association of Transportation Officials’ (AASHTO’s) design guidance need to be evaluated. NCHRP Web-Only Document 264: Proposed Enhancements to Pavement ME Design: Improved Consideration of the Influence of Subgrade and Unbound Layers on Pavement Performance proposes and develops enhancements to AASHTO's Pavement ME Design procedures for both flexible and rigid pavements, which will better reflect the influence of subgrade and unbound layers (properties and thicknesses) on the pavement performance.
Book Synopsis Quantifying the Influence of Geosynthetics on Pavement Performance by :
Download or read book Quantifying the Influence of Geosynthetics on Pavement Performance written by and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Effect of Subgrade Conditions on Pavement Analysis and Performance Prediction by : Md Jibon
Download or read book Effect of Subgrade Conditions on Pavement Analysis and Performance Prediction written by Md Jibon and published by . This book was released on 2019 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The Mechanistic-Empirical (M-E) pavement design approach detailed in the Mechanistic-Empirical Pavement Design Guide (MEPDG), and subsequently implemented through AASHTOWare® Pavement ME Design relies extensively on detailed material properties that ultimately govern the analysis and performance prediction results. For unbound materials like soils and aggregates, Resilient Modulus (MR) is the most critical input parameter affecting layer response under vehicular and environmental loading. Representing a material’s ability to ‘recover’ after loading, resilient modulus is determined in the laboratory through repeated load triaxial testing. Although the original test protocol to measure the resilient modulus value of a soil or aggregate was developed back in the 1980’s, this test is still not widely used by state highway agencies because it is cumbersome, and requires significant investments towards equipment and personnel training. Accordingly, most agencies rely on correlation equations to predict the resilient modulus values for soils and aggregates from other easy-to-determine material properties. However, these correlation equations are mostly region specific, and therefore, do not produce adequate results across different geographic regions. This has led several state highway agencies to undertake local calibration efforts for improved prediction of material properties. Over the past decade, the Idaho Transportation Department (ITD) has invested significant resources to facilitate state-wide implementation of mechanistic-empirical pavement design practices. A research study was recently undertaken by ITD to develop a database of resilient modulus properties for different soils and aggregates commonly used in the state of Idaho for pavement applications. Another objective of the study was to assess the adequacy of different correlation equations currently available to predict soil and aggregate resilient modulus from easy-to-determine material (strength and index) properties. This Master’s thesis is based on tasks carried out under the scope of the above-mentioned project, and focuses on laboratory characterization and analysis of representative subgrade soil types collected from across Idaho. An extensive laboratory test matrix was developed involving commonly used mechanical and index tests, repeated load triaxial tests for resilient modulus determination, as well as tests to study the soil permanent deformation (plastic strain) behavior. Effect of moisture variation on soil strength, modulus, and permanent deformation properties was also studied by testing soil specimens at three different moisture contents. The test results were thoroughly analyzed to evaluate the feasibility of predicting resilient modulus from other material properties. Findings from this research effort have been documented in the form of two journal manuscripts. The first manuscript highlights the importance of using adequate subgrade resilient modulus values during pavement design. Eight different soil types were randomly selected from a total of sixteen soil types, and the corresponding laboratory test results were used to highlight the limitations of ITD’s current approach with assumed resilient modulus values. The second manuscript focuses on highlighting the importance of unbound material permanent deformation characterization during pavement design, and how small changes in moisture content can lead to significant differences in the rutting behavior of subgrade soils. First, a new permanent deformation testing protocol was developed to simulate typical stress states experienced by subgrade layers under vehicular loading. Subsequently, permanent deformation tests were carried out on subgrade soil types collected from two distinctly different regions in Idaho as far as annual precipitation is concerned. Tests were conducted at three different moisture contents to highlight how the rutting potential of the subgrade may change significantly based on site precipitation and drainage characteristics. Finally, recommendations were made regarding how state highway agencies can accurately represent resilient modulus properties of soils during pavement analysis and performance prediction using AASHTOWare® Pavement ME Design."--Boise State University ScholarWorks.
Author :American Association of State Highway and Transportation Officials Publisher :AASHTO ISBN 13 :1560510552 Total Pages :622 pages Book Rating :4.5/5 (65 download)
Book Synopsis AASHTO Guide for Design of Pavement Structures, 1993 by : American Association of State Highway and Transportation Officials
Download or read book AASHTO Guide for Design of Pavement Structures, 1993 written by American Association of State Highway and Transportation Officials and published by AASHTO. This book was released on 1993 with total page 622 pages. Available in PDF, EPUB and Kindle. Book excerpt: Design related project level pavement management - Economic evaluation of alternative pavement design strategies - Reliability / - Pavement design procedures for new construction or reconstruction : Design requirements - Highway pavement structural design - Low-volume road design / - Pavement design procedures for rehabilitation of existing pavements : Rehabilitation concepts - Guides for field data collection - Rehabilitation methods other than overlay - Rehabilitation methods with overlays / - Mechanistic-empirical design procedures.
Author :American Association of State Highway and Transportation Officials Publisher :AASHTO ISBN 13 :156051423X Total Pages :218 pages Book Rating :4.5/5 (65 download)
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:
Book Synopsis Influence of Subgrade Improvement and Non-uniformity on Pavement Performance by : Tyson David Rupnow
Download or read book Influence of Subgrade Improvement and Non-uniformity on Pavement Performance written by Tyson David Rupnow and published by . This book was released on 2004 with total page 548 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis contains results from three projects describing self-cementing fly ash stabilization of RAP-soil mixtures, stabilization of limestone screenings for use as a structural layer in road construction, and finite element modeling results of various subgrade materials including self-cementing fly ash stabilized subgrade, natural subgrade, granular subbase, and hydrated fly ash. The first project shows that self-cementing fly ash stabilization of RAP-soil mixtures is economically feasible and structurally capable of supporting construction traffic. The increase stiffness from the addition of self-cementing fly ash increases capacity ensuring long term pavement performance. Addition of self-cementing fly ash increases the consolidated shear strength about five times. The second project shows construction operations and field results proving that stabilization of limestone screenings is viable, cost effective, and produces an adequate structural layer for road construction. The measured moisture-density curves for manufactured sand and limestone screenings are about the same, and the moisture-strength curves show a dramatic decrease in strength beyond the optimum moisture content for strength. Durability testing concluded that CKD stabilized manufactured sand and limestone screenings are not viable construction alternatives, and the addition of class C fly ash with CKD significantly increased the durability of the mixtures. The third project concluded that a link exists between subgrade non-uniformity and pavement performance. Field testing, with the DCP, Clegg Impact Hammer, nuclear density gauge, and GeoGauge, and statistical analysis of subgrade materials concluded that granular subbase, self-cementing fly ash treated subgrade, and HFA decrease the variability of field results. Finite element modeling analysis proved that a link exists between subgrade non-uniformity and pavement performance. Uniform modeling conditions produced lower average deflections and stresses increasing pavement life. Statistical analysis concluded that modeling uniform subgrade conditions produce average stresses that have less variability than those for non-uniform modeling conditions. Pavement response reliability increased with the addition of uniform subgrade, proving that subgrade non-uniformity influences pavement performance.
Book Synopsis Effects of Subsurface Drainage on Pavement Performance by : Kathleen Theresa Hall
Download or read book Effects of Subsurface Drainage on Pavement Performance written by Kathleen Theresa Hall and published by Transportation Research Board. This book was released on 2007 with total page 201 pages. Available in PDF, EPUB and Kindle. Book excerpt: NCHRP Report 583 explores the effects of subsurface drainage features on pavement performance through a program of inspection and testing of the subsurface drainage features present in the Long-Term Pavement Performance SPS-1 (flexible hot-mix asphalt pavement) and SPS-2 (rigid portland cement concrete pavement) field sections.
Book Synopsis Advances in Pavement Design through Full-scale Accelerated Pavement Testing by : David Jones
Download or read book Advances in Pavement Design through Full-scale Accelerated Pavement Testing written by David Jones and published by CRC Press. This book was released on 2012-10-08 with total page 560 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pack: Book and CDInternationally, full-scale accelerated pavement testing, either on test roads or linear/circular test tracks, has proven to be a valuable tool that fills the gap between models and laboratory tests and long-term experiments on in-service pavements. Accelerated pavement testing is used to improve understanding of pavement behavior,
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.
Book Synopsis Soil Stabilization in Pavement Structures: Pavement design and construction considerations by : Terrel, Epps, and Associates
Download or read book Soil Stabilization in Pavement Structures: Pavement design and construction considerations written by Terrel, Epps, and Associates and published by . This book was released on 1980 with total page 208 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Impact of Design Features on Pavement Response and Performance in Rehabilitated Flexible and Rigid Pavements by :
Download or read book Impact of Design Features on Pavement Response and Performance in Rehabilitated Flexible and Rigid Pavements written by and published by . This book was released on 2011 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt: The primary focus of this research was to determine the effects of design and construction features, such as overlay thickness and mix type, presence of milling, and type of restoration, on pavement response and performance and to establish their importance in the prediction of future performances of rehabilitated pavements. Long-Term Pavement Performance program Specific Pavement Study (SPS)-5 and SPS-6 experiments provided information to obtain a better understanding of the effects of design and construction features on pavement response and performance of rehabilitated flexible and rigid pavements.
Book Synopsis Development of Local Calibration Factors and Design Criteria Values for Mechanistic-empirical Pavement Design by : Bryan Smith
Download or read book Development of Local Calibration Factors and Design Criteria Values for Mechanistic-empirical Pavement Design written by Bryan Smith and published by . This book was released on 2015 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: A mechanistic-empirical (ME) pavement design procedure allows for analyzing and selecting pavement structures based on predicted distress progression resulting from stresses and strains within the pavement over its design life. The Virginia Department of Transportation (VDOT) has been working toward implementing ME design by characterizing traffic and materials inputs, training with the models and design software, and analyzing current pavement designs in AASHTOware Pavement ME Design software. This study compared the measured performance of asphalt and continuously reinforced concrete pavements (CRCP) from VDOTs Pavement Management System (PMS) records to the predicted performance in AASHTOware Pavement ME Design. Model coefficients in the software were adjusted to match the predicted asphalt pavement permanent deformation, asphalt bottom-up fatigue cracking, and CRCP punchout outputs to the measured values from PMS records. Values for reliability, design life inputs, and distress limits were identified as a starting point for VDOT to consider when using AASHTOware Pavement ME Design through consideration of national guidelines, existing VDOT standards, PMS rating formulas, typical pavement performance at time of overlay, and the data used for local calibration. The model calibration coefficients and design requirement values recommended in this study can be used by VDOT with AASHTOware Pavement ME Design as a starting point to implement the software for design, which should allow for more optimized pavement structures and improve the long-term performance of pavements in Virginia.
Book Synopsis Design Considerations for Flexible Pavement Widening by : Stacy L. Hilbrich
Download or read book Design Considerations for Flexible Pavement Widening written by Stacy L. Hilbrich and published by . This book was released on 2007 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Stabilization of Existing Subgrades to Improve Constructibility During Interstate Pavement Reconstruction by : Joakim G. Laguros
Download or read book Stabilization of Existing Subgrades to Improve Constructibility During Interstate Pavement Reconstruction written by Joakim G. Laguros and published by . This book was released on 1997 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt: This synthesis will be of interest to state department of transportation (DOT) construction, geotechnical, materials, and pavement system design engineers, engineering geologists, and research engineers, and others concerned with the constructibility of new pavements over existing subgrades. The synthesis describes current practice for the stabilization of existing subgrades to improve constructibility during interstate pavement reconstruction. It presents information regarding the methods available to evaluate and improve subgrade conditions for the purpose of meeting the constructibility requirements of a reconstruction project. This report of the Transportation Research Board presents data obtained from a review of the literature and a survey of the state DOTs. The synthesis reports on: subgrade evaluation methods including sampling, laboratory, and in-situ test methods, as well as assessment of existing drainage systems; constructibility factors such as existing and proposed pavement types, available equipment, and cost effectiveness of various subgrade stabilization techniques; methods of subgrade improvement including mechanical and chemical stabilization, use of recycled and waste materials, the use of geosynthetics in reinforcement and drainage applications; and construction methods with an emphasis on innovative approaches such as novel sequencing of construction traffic, use of lightweight equipment, and robotics. In addition, several case histories describing applicable pavement reconstruction projects are presented. Finally, suggestions to possibly improve the practice and the identification of research needs are also presented.
Book Synopsis Feasibility of the Use of Existing Analytical Models and Experimental Data to Assess Current Design Methods for Pavement Geogrid-reinforced Base Layers by : Steven W. Perkins
Download or read book Feasibility of the Use of Existing Analytical Models and Experimental Data to Assess Current Design Methods for Pavement Geogrid-reinforced Base Layers written by Steven W. Perkins and published by . This book was released on 1995 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt: In recent years polymer geogrids have been proposed and used to improve the performance of paved roadways and/or to reduce base course thickness. Performance improvements have been demonstrated for design conditions where relatively large rut depths are acceptable and where relatively weak pavement sections have been used. This work was undertaken to examine existing literature concerning laboratory and field experimental studies, and analytical studies pertaining to the inclusion of geogrid polymer materials in roadway pavement sections for the purpose of improving performance or to allow for a reduction in the constructed section thicknesses. The original goal of this study was to examine the feasibility of using existing data from laboratory or field studies and existing finite element models to validate and calibrate the model and then use the model to predict the response of pavement sections not included in the experimental studies. This study has indicated that this approach is feasible and has been accomplished by a previous project. Furthermore, the literature reviewed in this study has shown conflicting results pertaining to the level of improvement that is realized by inclusion of a geogrid in the base course layer of a pavement section. While additional laboratory and analytical studies may aid in resolving these conflicts it is concluded that the most productive approach at this point is to construct well instrumented, full scale field sections to assess improvement levels. These sections should be designed and constructed to include variables identified in previous studies as having the greatest impact on pavement performance.
Book Synopsis Using Multi-objective Optimization to Enhance Calibration of Performance Models in the Mechanistic-Empirical Pavement Design Guide by : Nima Kargah-Ostadi
Download or read book Using Multi-objective Optimization to Enhance Calibration of Performance Models in the Mechanistic-Empirical Pavement Design Guide written by Nima Kargah-Ostadi and published by . This book was released on 2018 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt: This research study devised two scenarios for application of multi-objective optimization to enhance calibration of performance models in the American Association of State Highway and Transportation Officials (AASHTO) AASHTOWare® Pavement ME Design software.(1) In the primary scenario, mean and standard deviation of prediction error are simultaneously minimized to increase accuracy and precision at the same time. In the second scenario, model prediction error on data from Federal Highway Administration’s Long-Term Pavement Performance test sections and error on available accelerated pavement testing data are treated as independent objective functions to be minimized simultaneously. The multi-objective optimization results in a final pool of tradeoff solutions, where none of the viable sets of calibration factors are eliminated prematurely. Exploring the final front results in more reasonable calibration coefficients that could not be identified using single-objective approaches. This report demonstrates the application of engineering judgment and qualitative criteria to select reasonable calibration coefficients from the final pool of solutions that result from the multi-objective optimization. More reasonable calibration factors result in a more justifiable pavement design considering multiple aspects of pavement performance. This investigation revealed that simply evaluating the bias and standard error is not adequate for a comprehensive evaluation of performance prediction models.
Book Synopsis Pavement Subgrade Performance Study by : Vincent C. Janoo
Download or read book Pavement Subgrade Performance Study written by Vincent C. Janoo and published by . This book was released on 2003 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mechanistic design or evaluation of pavements requires fundamental material properties and material failure criteria as a function of load and environmental effects such as temperature and moisture content. The strength or weakness of a pavement structure is based on the performance of the subgrade. The current subgrade failure criteria used in many mechanistic design/evaluation methodologies were surmised mainly from tests that did not consider the effects of subgrade soil type or moisture content. Because of these limitations the current FHWA-sponsored Subgrade Performance Study was designed to investigate and upgrade the failure criteria of subgrade materials. The project plans to study the effect of subgrade type and moisture content on the failure criteria. This international study includes testing at the U.S. Army Cold Regions Research and Engineering Laboratory where test sections are being constructed using four subgrade types and three moisture contents and subjected to accelerated loading. The sections are instrumented with stress strain moisture and temperature sensors. In this study the ambient temperature is held at around 20 deg C. This report provides an overview of the test program and testing procedure. Subsequent reports will detail the construction of each test section the data acquired and the results.
