Search

Accurate identification of factors that primarily affect the number of low-temperature cracks is crucial for selection of road materials and planning of pavement maintenance. Field investigations of low-temperature cracks were performed in the years 2014 and 2020 on the same 68 road sections being in service in typical traffic conditions. The collected data were statistically analysed using the ordered logistic regression model. Comparison of the odds ratios which were calculated on the basis of the model enabled ordering of the selected factors from those having the greatest effect on low-temperature cracking of pavements to those with the least influence: (1) pavement age, (2) type of asphalt concrete, (3) modification of bitumen, (4) climatic zone (on the basis of low performance grade temperature). The odds of a section belonging to the group of cracked sections decreased by half when a polymer-modified bitumen was used in its binder course and asphalt base. Regardless of the considered factors, the odds of a pavement section being classified into the group of heavily cracked sections are comparable. It means that some external factors, including quality of paving works and bitumen chemistry, may prove the most crucial. [ABSTRACT FROM AUTHOR]

Weigh-in-Motion (WIM) systems are used in order to reduce the number of overloaded vehicles. Data collected from WIM provide characteristics of vehicle axle loads that are crucial for pavement design as well as for the development of pavement distress prediction models. The inaccuracy of WIM data lead to erroneous estimation of traffic loads and in consequence inaccurate prediction of pavement distress process. The objective of the paper is to present a new methodology of heavy traffic axle load spectra (ALS) correction due to weighing errors (systematic and random) that occur in WIM systems. The theoretical solution which is proposed in the paper was validated successfully. The method enables correction of erroneous data to make traffic load statistics used for pavement design more reliable and precise, with no necessity to remove high number of records, as it is used in other methods. The practical meaning of the newly developed method was emphasised by analysis of the effect of relative and random error of WIM data on pavement fatigue life estimation, as well as on the estimated percentage of overloaded vehicles. Mechanistic-empirical approach (M-EPDG) was used for this purpose. [ABSTRACT FROM AUTHOR]