Download or read book Physically Meaningful Harmonization of Tire Pavement Friction Measurement Devices written by Madhura Priyanga Nishshanke Rajapakshe and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A set of laboratory tire experiments was designed and performed to validate the physical significance of LuGre tire model parameters and to study how they behave under typical load, inflation pressure, excitation frequency, and amplitude conditions. An empirical method was developed to accommodate the effects of water film thickness on tire/pavement friction in the LuGre model. The results of the sensitivity analysis and the experiments to directly estimate the model parameters were used to identify and quantify appropriate modifications to the measurement mechanisms of PFMDs that can be introduced to improve the comparability of their results. Friction experiments performed after introducing such modifications to the LWST showed an average reduction of 20% in the deviations between the results of LWST and RFT measurements. The research carried out in this dissertation is significant because it: (i) identified the deficiencies in the current method for harmonizing PFMD measurements and the underlying reasons for these deficiencies, (ii) emphasized the importance of a standardization approach that regulates the physical condition of PFMDs, in order to achieve universal comparability of tire/pavement friction measurements, (iii) validated that the LuGre tire model is a tire/pavement friction model capable of facilitating a better standardization approach, and, (iv) initialized the development of a physically meaningful harmonization procedure for PFMDs.

Download or read book Frictional Interaction of Tire and Pavement written by W. E. Meyer and published by ASTM International. This book was released on 1983 with total page 344 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Tire pavement Interaction Experimental Measurements and Modeling written by Mohammad O. Al-Assi and published by . This book was released on 2019 with total page 432 pages. Available in PDF, EPUB and Kindle. Book excerpt: Providing an adequate level of skid resistance is essential for the safety of motorists. Previous studies demonstrated that the number of crashes is reduced if pavements have sufficient friction, especially in wet conditions. Adequate pavement friction prevents the vehicle from sliding on the pavement surface and provides the grip needed to maintain control over the vehicle. The first phase of this study investigated experimentally the two major friction mechanisms (i.e., adhesion and hysteresis) that contribute to tire-pavement friction. It is postulated that the adhesion between rubber tires and pavements is highly influenced by the surface free energy. However, there are no previous studies carried out to investigate the adhesion between rubber tires and pavements using the surface free energy. The results demonstrated that adhesion friction can be quantified by measuring the surface free energy components of pavement surface aggregates and rubber materials. There was a fair correlation between the adhesive bond energy and the measured coefficient of friction. Higher adhesion between rubber materials and pavement surface provided higher friction. These results provide a fundamental understanding of the mechanisms of rubber-pavement friction and verification of the relationship between adhesion and friction. In addition, there was a strong correlation between friction and rubber rheological properties. Rubber materials with lower modulus provided higher friction compared to those with higher modulus. These results explain the change in skid resistance with temperature throughout the year. The second phase of this study examined different factors that affect skid resistance of pavement surfaces. These parameters included macrotexture, microtexture, and driving speed. The macrotexture of the pavement is related to aggregate gradation of the mix or surface texture pattern. The microtexture is influenced by the roughness of the aggregate particles and their resistance to abrasion and polishing under traffic. This study proposed a new model that can be used to estimate the skid number at a given speed between 20 mph and 60 mph as a function of both macrotexture and microtexture of pavement surface. This model was developed based on the measured frictional characteristics of field test sections. The proposed model can be used if the full-scale friction tester is not available or cannot be used due to the limited length of the test section (e.g., bridge deck). In addition, the model provides a tool to the pavement engineers to ensure adequate skid resistance at various operation speeds during the mix design stage and before the mix is used in the field. A given mix design can be modified to improve its frictional characteristics at early stage which leads to cost savings often spent on the application of surface treatments. The third phase of this study utilized the close-range photogrammetry (CRP) technique to measure the pavement macrotexture and microtexture. Texture parameters were calculated from the collected and analyzed images of the pavement surface. The results of the CRP texture measurements were compared to standard test methods. The CRP texture measurements had excellent correlation with the standard methods; however, the CRP offers simple and accurate, yet inexpensive alternative to the current methods used to measure surface macrotexture and microtexture. In addition, the CRP texture parameters were incorporated in the Persson friction model to predict skid friction as a function of rubber properties. The results demonstrated excellent correlation between measured and predicted friction. This study greatly simplified the texture parameter calculations needed in the Persson friction model with good accuracy.The last component of this study developed a 3D finite element model to investigate the effect of surface characteristics along with rubber properties on the contact stress between the standard skid test tire and pavement surface. Such simulation provides an in-depth understanding of tire-pavement interaction that would require expensive resources to examine in the field. Study parameters included various coefficient of friction, texture (e.g., smooth, and grooved), tire rolling conditions (fully skidding and free rolling) as well as temperature. The developed 3D FE model of the test tire was first validated with laboratory measurements before it was used to examine the effect of the study parameters on tire-pavement contact stresses. The results of the finite element simulations demonstrated that the stress distribution at the tire-pavement interface is non-uniform with maximum values towards the edges of the tire. These findings were consistent with the wearing pattern of the test tire in the field. In addition, the results also demonstrated that the shear stresses increased with surface friction while there was no significant change in the vertical stresses. The grooved surface exhibited higher vertical and shear stresses compared to pavement with smooth texture. The grooved texture is used to improve skid resistance and reduce the noise of pavement surfaces. In addition, temperature was found to have significant impact on the stresses at the tire-pavement interface. The finite element simulation results agreed with the laboratory and field measurements of pavement friction.

Download or read book Guide for Pavement Friction written by and published by AASHTO. This book was released on 2008 with total page 87 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report contains guidelines and recommendations for managing and designing for friction on highway pavements. The contents of this report will be of interest to highway materials, construction, pavement management, safety, design, and research engineers, as well as others concerned with the friction and related surface characteristics of highway pavements.

Download or read book Field Calibration of an Analytical Model for Pavement Friction Testing Applications written by H. N. Seneviratne and published by . This book was released on 2009 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: Regular evaluation and maintenance of skid resistance (friction) of highway and runway pavements is an essential task in improving transportation safety. Various measuring devices operating under different mechanisms have been developed for friction evaluation. Generally, there is a significant variation of friction measurements provided by different devices on the same surface, requiring reliable guidelines for comparison of devices. This paper presents the results of a study conducted to verify whether the LuGre model, an existing dynamic friction model composed of physically significant parameters, would satisfy the above need. A revised formulation which would enhance the applicability of the average lumped version of the LuGre model to model real-world dynamic friction problems is also presented. The original LuGre model was applied to two widely used pavement friction measuring devices; the locked wheel skid trailer and the dynamic friction tester (DFT). In the work presented here the characteristic equations for each device have been formulated based on the LuGre model. In addition an analytical treatment of the kinetics of the DFT is performed to facilitate the application of the LuGre model to the DFT. For each device, the LuGre model parameters were tuned to match a part of the field data collected during a field test carried out by the authors. It was seen that the obtained parameters are reasonably comparable with those reported in the literature. Moreover, the calibrated model equations were seen to predict the observed data that were not used in model fitting, with acceptable accuracy. The results obtained in this study clearly show that the LuGre model can be utilized as an efficient physically intuitive tool with possible applications in: (1) predicting the three-dimensional variation of friction (with wheel slip and traveling speed) as measured by selected friction measuring devices, (2) providing physical interpretations to friction data from different devices, (3) regular self-calibration of friction devices, and (4) comparing pavement friction measurements from different devices.

Download or read book Chassis Handbook written by Bernhard Heißing and published by Springer Science & Business Media. This book was released on 2010-11-09 with total page 611 pages. Available in PDF, EPUB and Kindle. Book excerpt: In spite of all the assistance offered by electronic control systems, the latest generation of passenger car chassis still relies on conventional chassis elements. With a view towards driving dynamics, this book examines these conventional elements and their interaction with mechatronic systems. First, it describes the fundamentals and design of the chassis and goes on to examine driving dynamics with a particularly practical focus. This is followed by a detailed description and explanation of the modern components. A separate section is devoted to the axles and processes for axle development. With its revised illustrations and several updates in the text and list of references, this new edition already includes a number of improvements over the first edition.

Download or read book Pavement Design and Materials written by A. T. Papagiannakis and published by John Wiley & Sons. This book was released on 2017-02-22 with total page 555 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive, state-of-the-art guide to pavement design and materials With innovations ranging from the advent of SuperpaveTM, the data generated by the Long Term Pavement Performance (LTPP) project, to the recent release of the Mechanistic-Empirical pavement design guide developed under NCHRP Study 1-37A, the field of pavement engineering is experiencing significant development. Pavement Design and Materials is a practical reference for both students and practicing engineers that explores all the aspects of pavement engineering, including materials, analysis, design, evaluation, and economic analysis. Historically, numerous techniques have been applied by a multitude of jurisdictions dealing with roadway pavements. This book focuses on the best-established, currently applicable techniques available. Pavement Design and Materials offers complete coverage of: The characterization of traffic input The characterization of pavement bases/subgrades and aggregates Asphalt binder and asphalt concrete characterization Portland cement and concrete characterization Analysis of flexible and rigid pavements Pavement evaluation Environmental effects on pavements The design of flexible and rigid pavements Pavement rehabilitation Economic analysis of alternative pavement designs The coverage is accompanied by suggestions for software for implementing various analytical techniques described in these chapters. These tools are easily accessible through the book’s companion Web site, which is constantly updated to ensure that the reader finds the most up-to-date software available.

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 Motor Vehicle Dynamics Modelling And Simulation written by Giancarlo Genta and published by World Scientific. This book was released on 1997-04-19 with total page 552 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book starts with an historical overview of road vehicles. The first part deals with the forces exchanged between the vehicle and the road and the vehicle and the air with the aim of supplying the physical facts and the relevant mathematical models about the forces which dominate the dynamics of the vehicle.The second part deals with the dynamic behaviour of the vehicle in normal driving conditions with some extensions towards conditions encountered in high-speed racing driving.

Download or read book Water in Road Structures written by Andrew Dawson and published by Springer Science & Business Media. This book was released on 2008-10-21 with total page 454 pages. Available in PDF, EPUB and Kindle. Book excerpt: Only book world-wide addressing this topic. The principal output of the European co-operative Action on "Water Movements in Road Pavements & Embankments". Provides unique guidance on assessing water condition and its affects on road performance. Provides unique guidance on assessing and ameliorating contaminant movement in pavement groundwater. Written by leading experts in Europe.

Download or read book Highway Design and Traffic Safety Engineering Handbook written by Ruediger Lamm and published by McGraw-Hill Professional Publishing. This book was released on 1999-01-01 with total page 1088 pages. Available in PDF, EPUB and Kindle. Book excerpt: Truly unique, this is the first book to present a thoroughly scientific and practical approach to designing highways for maximum safety. Based on original research plus scrupulously collected data amassed over more two decades in different continents by the main author, this important book originates vital criteria for safe design and shows you how best to achieve roads with the lowest possible accident risk and severity rates. A true must-read for highway engineers and safety officials, Highway Design and Traffic Safety Engineering Handbook provides up-to-date information that is available nowhere else and a complete, practical program for designing the safest possible roadways. The authors, who are noted international authorities on highway safety, give you essential information on sound new designs, design cases to avoid, examples of good and poor solutions, the redesign of existing roads, and far more. In addition, this valuable and necessary resource gives you serious help coordinating safety concerns with important economic, environmental, and aesthetic considerations. The new standard in highway design methods, this book will become a keystone in every highway designer's library.

Download or read book Non Exhaust Emissions written by Fulvio Amato and published by Academic Press. This book was released on 2018-01-02 with total page 344 pages. Available in PDF, EPUB and Kindle. Book excerpt: Non-Exhaust Emissions: An Urban Air Quality Problem for Public Health comprehensively summarizes the most recent research in the field, also giving guidance on research gaps and future needs to evaluate the health impact and possible remediation of non-exhaust particle emissions. With contributions from some of the major experts and stakeholders in air quality, this book comprehensively defines the state-of-the-art of current knowledge, gaps and future needs for a better understanding of particulate matter (PM) emissions, from non-exhaust sources of road traffic to improve public health. PM is a heterogeneous mix of chemical elements and sources, with road traffic being the major source in large cities. A significant part of these emissions come from non-exhaust processes, such as brake, tire, road wear, and road dust resuspension. While motor exhaust emissions have been successfully reduced by means of regulation, non-exhaust emissions are currently uncontrolled and their importance is destined to increase and become the dominant urban source of particle matter by 2020. Nevertheless, current knowledge on the non-exhaust emissions is still limited. This is an essential book to researchers and advanced students from a broad range of disciplines, such as public health, toxicology, atmospheric sciences, environmental sciences, atmospheric chemistry and physics, geochemistry, epidemiology, built environment, road and vehicle engineering, and city planning. In addition, European and local authorities responsible for air quality and those in the industrial sectors related to vehicle and brake manufacturing and technological remediation measures will also find the book valuable. Acts as the first book to explore the health impacts of non-exhaust emissions Authored by experts from several sectors, including academia, industry and policy Gathers the relevant body of literature and information, defining the current knowledge, gaps and future needs

Download or read book Eco efficient Pavement Construction Materials written by Fernando Pacheco-Torgal and published by Woodhead Publishing. This book was released on 2020-01-18 with total page 422 pages. Available in PDF, EPUB and Kindle. Book excerpt: Eco-efficient Pavement Construction Materials acquaints engineers with research findings on new eco-efficient pavement materials and how they can be incorporated into future pavements. Divided into three distinctive parts, the book emphasizes current research topics such as pavements with recycled waste, pavements for climate change mitigation, self-healing pavements, and pavements with energy harvesting potential. Part One considers techniques for recycling, Part Two reviews the contribution of pavements for climate change mitigation, including cool pavements, the development of new coatings for high albedo targets, and the design of pervious pavements. Finally, Part Three focuses on self-healing pavements, addressing novel materials and design and performance. Finally, the book discusses the case of pavements with energy harvesting potential, addressing different technologies on this field. Offers a clear and concise lifecycle assessment of asphalt pavement recycling for greenhouse gas emission with temporal aspects Applies key research trends to green the pavement industry Includes techniques for recycling waste materials, the design of cool pavements, self-healing mechanisms, and key steps in energy harvesting

Download or read book The Dancing Wu Li Masters written by Gary Zukav and published by Harper Collins. This book was released on 2009-10-06 with total page 606 pages. Available in PDF, EPUB and Kindle. Book excerpt: “The most exciting intellectual adventure I've been on since reading Robert Pirsig’s Zen and the Art of Motorcycle Maintenance.” —Christopher Lehmann-Haupt, New York Times Gary Zukav’s timeless, humorous, New York Times bestselling masterpiece, The Dancing Wu Li Masters, is arguably the most widely acclaimed introduction to quantum physics ever written. Scientific American raves: “Zukav is such a skilled expositor, with such an amiable style, that it is hard to imagine a layman who would not find his book enjoyable and informative.” Accessible, edifying, and endlessly entertaining, The Dancing Wu Li Masters is back in a beautiful new edition—and the doors to the fascinating, dazzling, remarkable world of quantum physics are opened to all once again, no previous mathematical or technical expertise required.

Download or read book Impact of Airport Rubber Removal Techniques on Runways written by Douglas D. Gransberg and published by Transportation Research Board. This book was released on 2008 with total page 119 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Border Management Modernization written by Gerard McLinden and published by World Bank Publications. This book was released on 2010-11-30 with total page 401 pages. Available in PDF, EPUB and Kindle. Book excerpt: Border clearance processes by customs and other agencies are among the most important and problematic links in the global supply chain. Delays and costs at the border undermine a country’s competitiveness, either by taxing imported inputs with deadweight inefficiencies or by adding costs and reducing the competitiveness of exports. This book provides a practical guide to assist policy makers, administrators, and border management professionals with information and advice on how to improve border management systems, procedures, and institutions.

Download or read book Ergonomics in the Automotive Design Process written by Vivek D. Bhise and published by CRC Press. This book was released on 2016-04-19 with total page 329 pages. Available in PDF, EPUB and Kindle. Book excerpt: The auto industry is facing tough competition and severe economic constraints. Their products need to be designed "right the first time" with the right combinations of features that not only satisfy the customers but continually please and delight them by providing increased functionality, comfort, convenience, safety, and craftsmanship. Based on t