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The design of asphalt pavements – a predominantly American initiative
Published in Maxwell Lay, John Metcalf, Kieran Sharp, Paving Our Ways, 2020
Maxwell Lay, Metcalf John, Sharp Kieran
A major step forward occurred with the AASHO Road Test in the late 1950s which involved testing full-scale pavements under real truck traffic.684 The tests are discussed in more detail in Chapters 19 and 20. One key finding was that the then-current thin asphalt layers were ineffective under heavy traffic. This led the American asphalt industry to move quickly to promote pavements constructed solely of a thick asphalt layer, avoiding the use of a concrete lower layer which had been common practice for the previous hundred or so years. Pavements comprised of an asphalt layers placed directly on the subgrade are now commonly called full depthasphalt pavements. Pavements where the asphalt layers are placed on a layer of broken stones or stabilised material (Chapter 18) which in turn rest on the subgrade are commonly called deep lift asphalt pavements or, more positively, deep strength asphalt pavements.685 The AASHO Road Test also produced a pavement design manual686 which has subsequently dominated American pavement design. Major updates – still based largely on the Road Test results – were issued in 1972 and 1993.
Pavement rutting prediction models for the coastal roads of southern Norway
Published in Andreas Loizos, Imad L. Al-Qadi, A. (Tom) Scarpas, Bearing Capacity of Roads, Railways and Airfields, 2017
Accurate prediction of pavement performance is important for proper management of pavement infrastructure for a highway agency. As a result, prediction of pavement performance is a major task in pavement management. Since the AASHO road test in the 1960’s (Carey and Irick 1960), a lot of pavement performance prediction models have been developed for predicting pavement condition. The majority of these models use empirical relationships developed from laboratory and/or field experimental data (Hasan Ziari 2015) (Svensson 2012).
Pavement performance depends on integration of design and management
Published in Sandra Erkens, Xueyan Liu, Kumar Anupam, Yiqiu Tan, Functional Pavement Design, 2016
In 1957–1961, the AASHO Road Test (Highway Research Board 1962), a $500 million controlled experiment [in today’s dollars] was conducted “to solve once and for all” the problems of pavement design and construction. The results of this test were widely analyzed and incorporated into the very first pavement design guide ever produced by AASHTO. It was used in Texas and other states from 1962 but was only accepted by AASHTO as an interim guide in 1972 (Haas et al. 1994). The Guide includes design equations for rigid and flexible pavements. These design principles were widely used in the design of interstate and primarily highways in the United States and around the world since 1965.
Generalised clusterwise regression for simultaneous estimation of optimal pavement clusters and performance models
Published in International Journal of Pavement Engineering, 2020
Mukesh Khadka, Alexander Paz, Ashok Singh
In the field of Pavement Management, Luo and Chou (2006) introduced CR to model pavement deterioration. A sigmoidal (S-shaped) functional form was used to relate a pavement condition rating to age. Later, Luo and Yin (2008) extended their study to model the development of pavement distresses in flexible pavements. In both studies, only pavement age was used as an explanatory variable. These studies did not investigate the combined effect of multiple explanatory variables within the CR framework. Other variables that are proven as critical factors on pavement deterioration, such as traffic loading conditions, pavement structure, and environmental conditions, were not investigated. Zhang and Durango-Cohen (2014) addressed this limitation by including multiple explanatory variables within the CR framework to estimate pavement serviceability. A nonlinear model specification was used to model present serviceability index (PSI) with explanatory variables – structural number, frost gradient and cumulative as well as incremental traffic. The study used data collected during the AASHO Road Test (Highway Research Board 1962), which was performed in a single site with a relatively controlled environment. The results indicated that pavement segments under similar traffic loading and environmental conditions showed heterogenous performance. In addition, the study confirmed that the CR framework is effective to capture such heterogeneity in the effect of explanatory variables while minimising the overall estimation error.
Special issue on Advances in Pavement Design, Management, Financing, and Data Automation
Published in Transportmetrica A: Transport Science, 2019
Kelvin C. P. Wang, Zhanmin Zhang
Since the American Association of State Highway Officials (AASHO) Road Test was conducted more than half a century ago, pavements engineering practices have been evolving from empirical approaches to mechanistic design and data-driven management. Particularly in recent years, hybrid design methodologies based on mechanistic-empirical processes are being studied and implemented in the U.S. and other parts of the world. At the same time, management of pavement assets is leading the way for transportation infrastructure asset management including nearly all man-made elements on and around highways. To support various pavement design and management purposes, data collection and its automation are becoming an important topic among practitioners and researchers around the world. This special issue on Advances in Pavement Design, Management, Financing, and Data Automation includes a total of nine papers covering a diverse range of topics such as asphalt and concrete materials, highway project financing, safety and pavement roughness, condition assessment, uncertainties in pavement maintenance, and the new Mechanistic-Empirical (ME) pavement designs.
Pavement serviceability evaluation using whole body vibration techniques: a case study for urban roads
Published in International Journal of Pavement Engineering, 2021
Luis Fuentes, Rafael Camargo, Gilberto Martínez-Arguelles, Julius J. Komba, Bhaven Naik, Lubinda F. Walubita
In the AASHO Road Test, it was demonstrated that from the different variables contemplated in the field experiment to evaluate the overall pavement condition, the surface roughness of the longitudinal pavement profile, described in terms of SV, was the variable that best described the users’ ratings (AASHO 1962b). Since then, different concepts have been explored to relate the pavement surface roughness to pavement serviceability. The IRI is one such concept and plays a key role in the pavement condition assessment in many countries around the world (Múčka 2017a).