Download or read book Road Surface Micro and Macrotexture Influence on Skid Resistance written by Murat Ergün and published by . This book was released on 1997 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The fast development of car technology has led to a steady increase ofthe speed of the vehicles. International studies show that increase causes increase in the accidents. The transport infrastructure such as pavement surface texture has not followed this development. In the wet weather, even at low speed, the skid resistance between the road surface and tyre can be quite low. International studies emphasise that there is a relation between the accident rate and the friction coefficient. The main goal of this study is to analyse the influence of road surface texture on skid resistance. The ultimate goal is to investigate the possibility of assessing pavement skid resistance by means of a new model which only uses surface texture parameters. In Chapter 1, the influence of skid resistance on the accident rates isexplained. Then, necessity of monitoring to road surface texture is highlighted. Thedefination of the surface texture is made in Chapter 2. The main surface texturedescriptors are surface texture (microtexture, macrotexture, and megatexture) and(un)evenness (longitudinal- and transverse evenness). The measuring methods ofsurface texture and (un)evenness are explained in Chapter 3. The description of skid resistance is explained from the historical development point of view in Chapter 4. In Chapter 5, the measuring methods of skid resistance are explained. Nowadays, different methods are in use to measure skid resistance.The main factors that affect skid resistance are pavement surface texture, the tyre, vehicle speed, and water film thickness as explained in Chapter 6. Recent researches on those factors are demonstrated. Then, the previously proposed models about skid resistance are explained in Chapter 7. In Chapter 8, the tests to study the influence of surface micro- and macrotexture on skid resistance are explained as mainly field and laboratory tests.The field tests are namely: skid resistance test by Odoliograph, the macrotexture by Mobile Laser Profilometer, and low-speed skid resistance spot tests by British Pendulum. Then, the cores are extracted from these spots. In the laboratory test, the new contactless microtexture measurement method is developed by using the Image Analysis Technique and applied on the extracted cores to measure microtexture of samples.The results of field and laboratory tests are presented in Chapter 9. The analysis of the results is made in Chapter 10.Finally, this study concluded that it is possible to predict the skid resistance of road surfaces by means of a new model which only uses surface texture parameters. Also, the road surface microtexture can be measurable with using the Image Analysis Technique. This study shows that it should be possible for systematic network monitoring of low friction spots on the road surface by using fast, non-contact texture measurement methods in the future.

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 Eleventh International Conference on the Bearing Capacity of Roads Railways and Airfields written by Inge Hoff and published by CRC Press. This book was released on 2021-11-10 with total page 501 pages. Available in PDF, EPUB and Kindle. Book excerpt: Innovations in Road, Railway and Airfield Bearing Capacity – Volume 1 comprises the first part of contributions to the 11th International Conference on Bearing Capacity of Roads, Railways and Airfields (2022). In anticipation of the event, it unveils state-of-the-art information and research on the latest policies, traffic loading measurements, in-situ measurements and condition surveys, functional testing, deflection measurement evaluation, structural performance prediction for pavements and tracks, new construction and rehabilitation design systems, frost affected areas, drainage and environmental effects, reinforcement, traditional and recycled materials, full scale testing and on case histories of road, railways and airfields. This edited work is intended for a global audience of road, railway and airfield engineers, researchers and consultants, as well as building and maintenance companies looking to further upgrade their practices in the field.

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 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 Development of a Prediction Model for Skid Resistance of Asphalt Pavements written by Arash Rezaei and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The skid resistance of asphalt pavement is a major characteristic that determines the driving safety on a road, especially under wet surface conditions. Skid resistance is primarily a function of the microtexture and macrotexture of a pavement surface. Microtexture is influenced by aggregate surface characteristics and is required to disrupt the continuity of surface water film and attain frictional resistance between the tire and the pavement surface. Macrotexture is affected mostly by mixture design or aggregate gradation and contributes to skid resistance by providing drainage paths of water that can be otherwise trapped between a tire and a pavement surface. The increase in macrotexture contributes to preventing hydroplaning and improving wet frictional resistance, particularly at high speeds. While much research has been conducted in the past to identify material factors that affect skid resistance, there is still a need to develop a model for predicting asphalt pavement skid resistance as a function of mixture characteristics and traffic level. The purpose of this study was to develop such a model based on extensive laboratory experiments and field measurements involving different mixture types and aggregate sources. The model incorporates functions that describe the resistance of aggregates to polishing and aggregate size distribution. The aggregate resistance to polishing was quantified by measuring aggregate texture using the Aggregate Imaging System (AIMS) before and after polishing in the Micro-Deval device. The analysis in this dissertation demonstrates how this model can be used to design mixtures and classify aggregates that provide desirable skid resistance levels.

Download or read book Roads and Airports Pavement Surface Characteristics written by Maurizio Crispino and published by CRC Press. This book was released on 2023-06-05 with total page 1066 pages. Available in PDF, EPUB and Kindle. Book excerpt: Roads and Airports Pavement Surface Characteristics contains the papers presented at the 9th International Symposium on Pavement Surface Characteristics (SURF 2022, Milan, Italy, 12-14 September 2022). The symposium was jointly organized by the Italian company that manages Italy’s National Roads (ANAS –Ferrovie dello Stato Italiane Group), the World Road Association (PIARC) and Politecnico di Milano. The contributions aim to improve the quality of pavement surface characteristics while accomplishing efficiency, safety, sustainability, and addressing new generation mobility needs. The book covers topics from emerging research to engineering practice, and is divided in the following sections: Advanced and performing construction methods and equipment Next generation mobility Data monitoring and performance assessment Surface features and performances| Maintenance and preservation treatments Pavement management Economic and political strategies Safety and risk issues Minimizing road impacts Sustainability and performances issues about materials and design Pavements surfaces and urban heat islands Weather conditions impact Airport pavements Roads and Airports Pavement Surface Characteristics is of interest to academics, engineers and professionals in the fields of pavement engineering, transport infrastructure, and related disciplines.

Download or read book Laboratory Evaluation of Pavement Surface Texture Characteristics in Relation to Skid Resistance written by S. H. Dahir and published by . This book was released on 1972 with total page 92 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Significance of Pavement Texture written by Glenn G. Balmer and published by . This book was released on 1975 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt: "This paper discusses the influence of roadway surface textures on the skid resistance, the speed-gradient, the wet-pavement accident rate, pavement wear, and the generation of tire-road interaction noise. The tendency of a vehicle to hydroplane is reduced by increasing the texture magnitude. Appropriate textures are developed by using open-graded asphalt friction surface courses and by grooving portland cement concrete with steel tines or a vibrating float while the concrete is plastic. Hardened pavements can be textured by grooving with a diamond saw or by resurfacing with an overlay. More development is needed in texture measurement techniques, especially in automating the stereo-photo interpretation method and the linear polarized laser technique"--Technical report documentation page

Download or read book Evaluation of Pavement Friction Characteristics written by John Jewett Henry and published by Transportation Research Board. This book was released on 2000 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt: This synthesis report will be of interest to pavement design, construction, management, and research engineers, highway safety officials, and others concerned with pavement friction characteristics. It describes the current state of the practice and discusses the methods used for evaluating wet pavement friction characteristics of new and restored pavements. This synthesis reviews models used for measuring and evaluating friction and texture, causes for friction changes over time, and aggregate and mix design to provide adequate friction. Also presented are construction and surface restoration practices for providing good pavement surface characteristics. In addition, considerations of noise and ride quality are discussed when compromise may be required.

Download or read book The Contribution of Micro and Macro texture to the Skid Resistance of Flexible Pavement written by Pedro Antonio Serigos and published by . This book was released on 2016 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Surface Characteristics of Roadways written by W. E. Meyer and published by ASTM International. This book was released on 1990 with total page 581 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Method for Rating the Skid Resistance and Micro Macrotexture Characteristics of Wet Pavements written by F. Buhlmann and published by . This book was released on 1983 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: A method is developed from combined viscous-dynamic hydroplaning theory to rate the skid resistance of wet pavements in terms of pavement microtexture and macrotexture drainage coefficients derived from full-scale tire-pavement friction tests. The friction tests can be conducted using any of the conventional tire test operating modes such as braked rolling, yawed rolling, or locked-wheel sliding. Once the drainage coefficients have been established for a wet pavement surface by friction test in a particular tire operating mode, the method can be used to predict friction coefficients on the wet pavement surface for the other tire operating modes, as well as friction coefficients for different-size tires and inflation pressure conditions. The procedure for using the method is described and examples are given. The method is used to evaluate the skid resistance, microtexture, and macrotexture characteristics of 83 highway pavements in Switzerland which were tested by The Institute of Technology (ISETH) using a skiddometer (locked-wheel test mode) over a 40 to 100-km/h speed range. The results obtained are compared with British pendulum, sand patch, and outflow meter tests of pavement surface texture also performed by ISETH on the same 83 highway pavements. Comparison with experimental data shows that the method gives reasonable estimates of friction coefficient for both aircraft and automobile tires for the examples cited.

Download or read book Skid Resistance of Highway Pavements written by and published by ASTM International. This book was released on 1973 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Advanced Materials and Structural Engineering written by Jong Wan Hu and published by CRC Press. This book was released on 2016-02-03 with total page 996 pages. Available in PDF, EPUB and Kindle. Book excerpt: The ICAMEST 2015 Conference covered new developments in advanced materials and engineering structural technology. Applications in civil, mechanical, industrial and material science are covered in this book. Providing high-quality, scholarly research, addressing developments, applications and implications in the field of structural health monitoring, construction safety and management, sensors and measurements. This volume contains new models for nonlinear structural analysis and applications of modeling identification. Furthermore, advanced chemical materials are discussed with applications in mechanical and civil engineering and for the maintenance of new materials. In addition, a new system of pressure regulating and water conveyance based on small and middle hydropower stations is discussed. An experimental investigation of the ultimate strength and behavior of the three types of steel tubular K-joints was presented. Furthermore, real-time and frequency linear and nonlinear modeling performance of materials of structures contents were concluded with the notion of a fully brittle material, and this approach is implemented in the book by outlining a finite-element method for the prediction of the construction performance and cracking patterns of arbitrary structural concrete forms. This book is an ideal reference for practicing engineers in material, mechanical and civil engineering and consultants (design, construction, maintenance), and can also be used as a reference for students in mechanical and civil engineering courses.

Download or read book Effect of Surface Macrotexture on Skid Resistance Measurements by the British Pendulum Test written by Y. Liu and published by . This book was released on 2004 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: The British pendulum test is a common procedure for laboratory as well as field measurement of the low-speed friction of a road surface material. It is widely suggested that the measured low-speed friction is largely governed by the surface microtexture of the road material, and many researchers and practitioners have considered the friction measurements made by the British pendulum test to be an indirect form of measurement of available microtexture of the road material. The experimental results presented in this paper show that this general view is not always correct. This study investigated the effects of test surface macrotexture represented by the following two geometric parameters: the size of subcontact areas and the magnitude of gaps between subcontact areas. The test results demonstrated that the low-speed friction measurements by the British pendulum tester were significantly affected by test surface macrotexture. This finding also implies that the closely packed aggregate condition required for the laboratory British pendulum test may not produce a correct assessment of the skid resistance of the true road surface. Laboratory measurements are likely to overestimate the skid resistance of a road surface if the surface aggregate spacing is wider than the spacing of the manually-packed laboratory specimens.

Download or read book Evaluation of Hot Mix Asphalt Macro and Microtexture written by M. Stroup-Gardiner and published by . This book was released on 2004 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pavement macrotexture is considered the primary factor in skid resistance at speeds over 65 km/h (40 mph). A total of 18 projects (9 Superpave and 9 Marshall mix designs) were evaluated to determine if the macrotexture of the pavement surface was influenced by gradation changes associated with the move to Superpave mix designs. The Federal Highway Administration ROSAN high-frequency laser system was used to measure macrotexture. Changes in microtexture, also a factor in skid resistance, were evaluated using a British Pendulum (BP) tester to determine the BP numbers of laboratory-compacted samples. Results indicated that the macrotexture did not change as a result of changes in mix design practices. The nominal maximum size of aggregate seemed to be the key factor in change in pavement surface macrotexture. Mixes, either Superpave or Marshall, with a nominal maximum size 9.5 mm or 12.5 mm have macrotextures of less than 0.5 mm. Based on information in the literature, the skid resistance for these Alabama pavements was estimated at 40 or higher.