Incorporation of Environmental Effects in Pavement Design (original) (raw)
Related papers
2019
Environmental conditions have a significant effect on the pavement performance. Of all the environmental factors, temperature and moisture have direct effect on the pavement layer and subgrade property. The current AASHTOWare Pavement ME software package utilizes the enhanced integrated climatic model (EICM) for applying the effects of climate on the pavement materials. The software uses historical climatic files that have been developed for each state in the US. However, these files are in most cases limited in number and region within each state, and therefore cannot represent the site-specific climate information. Furthermore, a number of states conducting research studies have found that there are significant discrepancies between the EICM predictions and measured values in the field. Therefore, there is a need to develop practical and implementable predictive models to study the moisture regime within the pavement subgrade in response to site specific climate data. This project...
Transportation Research Record: Journal of the Transportation Research Board, 2019
The Mechanistic-Empirical Pavement Design Guide addresses climate effects on pavement design in a comprehensive way, which allows for investigating the effect of climate on pavement performance. However, it requires detailed climate inputs, which might not be readily available for most of the state departments of transportation. The AASHTOWare Pavement Mechanistic-Empirical Design (PMED) version 2.3 (v2.3) climate database encompasses 12 weather stations in the state of Tennessee, which does not satisfactorily represent all climatic regions in the state. The terrain in Tennessee varies from flat in the west to mountainous in the east. To evaluate the effectiveness of the updated AASHTOWare PMED v2.3 climate data input, this study analyses the performance of selected pavements in the state of Tennessee using the Modern-Era Retrospective Analysis for Research and Applications (MERRA) and the AASHTOWare PMED v2.3 databases as sources of PMED climate data inputs. A comparative analysis ...
International Journal of Pavement Engineering, 2015
The purposes of this study were to establish the difference between empirical and mechanistic -empirical approaches in the flexible pavement design and to quantify the effects of mean annual precipitation and temperature on the flexible pavement distresses using the Mechanistic-Empirical Pavement Design Guide (MEPDG) software. Seventy-six specific locations from 13 states throughout the USA were selected based on different climate conditions using virtual climate stations based on the interpolation from the nearest weather stations prior to meeting the objectives. Subsequently, analysis was conducted based on the predicted distresses, including longitudinal cracking, transverse cracking, alligator cracking, asphalt concrete rutting and total pavement permanent deformation. Generally, the pavement structure and materials have been set as constant to control the effects of material on the results. On the basis of the MEPDG analysis, the longitudinal cracking of flexible pavement is significantly affected by both factors (temperature and precipitation), particularly in wet climatic regions. The mean annual temperature has a great influence on the alligator cracking, transverse cracking and permanent deformation of flexible pavement. However, neither factors demonstrated a significant impact on the predicted International Roughness Index of flexible pavement surfaces.
Effect of climate on asphalt pavement performance using two mechanistic-empirical methods
International Journal of Pavement Engineering, 2020
The objective of this study is to assess the impact of climate on the performance of bituminous pavements with two different methods, and then to examine their impact on actual design scenarios. Three climate cases were selected for the comparisons involving the effect of temperature: one in France (Bordeaux) and two in the United States (Seattle and Phoenix). The case of an experimental site in Québec was also used for comparisons concerning consideration for seasonal variations in ground bearing capacity. The analyses used two mechanistic-empirical approaches: the French method (NF P98-086 standard, LCPC-SETRA 1994 handbook, and the Alizé-LCPC software package) and the US method (NCHRP 2004 guide, AASHTO 2015 manual of practice, and the AASHTOWare Pavement ME Design software package). The results of the study highlight the importance, for design purposes, of the empirical fatigue equations as a function of temperature. For the site studied in France, the design results in terms of AC base layer thicknesses indicate that both methods show a similar trend with an increase in temperature. For the site in Québec, which is submitted to severe freeze/thaw cycles, the results show that taking temperature and moisture into account for unbound materials leads to a prediction of more severe permanent deformation.
The Implication of Climatic Changes to Asphalt Pavement Design
Procedia Engineering, 2015
The climatic characteristics in Slovakia are defined by the average daily air temperature and the average annual temperature and the frost index (during winter period). These are relevant input data for dimensioning of road construction (design and analysis based on thermal resistance). The research activities carried out by the authors brought the objectified correlation dependence of frost index values from the above sea level altitude. These results were objectified from measuring during period from 1971 to 2010. The results showed the differences between frost indexes from long-term monitoring and frost indexes determined according to STN 73 6114 Pavement of Roads Basic Provision for structural design. The using of the objectified correlation dependence of frost index is precondition for creating successful objectification of spending money to build roads, which are among the financially demanding civil engineering.
Quantifying the effect of climate change on the deterioration of a flexible pavement
Climate change raises challenges for conventional pavement design. With climate projections, deteriorations of a pavement can be analysed using the Mechanistic-Empirical Pavement Design Guide (MEPDG), under various global warming trends. The result exhibits to what extent climate change will have an impact on deteriorations of a flexible pavement. An alternative binder for the asphalt layers was considered in the simulation to investigate if a binder upgrade can mitigate the impact of possible climate change. The pavement is found to deteriorate more quickly due to temperature increase, although not very significantly. Moreover, a binder upgrade in the pavement design proved to be a possible mitigation against the effects of climate change on the chosen pavement.
Effect of Thermal Stresses on Pavement Performance under Mild Climate Conditions
Transportation Research Record: Journal of the Transportation Research Board, 2010
Thermal stress on the surfaces of pavements located in mild climates has been commonly considered to have a negligible effect on pavement performance. Current pavement design methodology focuses on maximum tensile stress rather than tensile stresses occurring over the design life of pavements. To identify the significance of thermal stress on pavement performance through structural stress analysis, this study investigated the predictive capability of the enhanced integrated climate model by comparing it with measured temperature data and introducing an analytical methodology of estimating thermal stress development using the dynamic modulus test. The identified thermal stresses were compared with the tensile stresses occurring at the bottom of an asphalt layer through the analysis method employed in the Guide for Mechanistic–Empirical Design of New and Rehabilitated Pavement Structures. Damage caused by the thermal and bottom stresses was evaluated on the basis of the damage ratio d...