Title First step to the development of performance based criteria for bitumen resistance to low temperature cracking
Authors Gražulytė, Judita ; Vaitkus, Audrius
eISBN 9789080288478
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Is Part of Proceedings of the 7th E&E Congress Eurasphalt & Eurobitume, 15–17 June 2021, Madrid, Spain.. Madrid : Foundation Eurasphalt, 2021. p. 1-8.. eISBN 9789080288478
Keywords [eng] dynamic shear rheometer test with 4 mm parallel plates ; low temperature cracking ; bitumen ; asphalt pavements
Abstract [eng] The existing standardized method for the determination of bitumen behaviour at low (negative) temperatures is based on bitumen prismatic beam bending – bending beam rheometer (BBR). However, BBR very often underestimates the performance of modified bitumens and needs approximately 15 g of bitumen for one specimen what may become a concern evaluating recovered and aged bitumens. A dynamic shear rheometer test with 4 mm parallel plates (4-mm DSR), introduced by Western Research Institute (WRI) in 2015, seems superior to other bitumen tests and methods dedicated to bitumen behaviour at low temperatures. However, WRI proposed limiting criteria for bitumen resistance to low temperature cracking (relaxation modulus (G) and apparent relaxation rate (mr) at a specific loading time of 60 s) are based on the BBR limits, which often fails in evaluating bitumen resistance to low temperature cracking. In addition, existing high precision DSRs allow direct measurements of relaxation modulus. Therefore, this paper focuses on the algorithm for the development of performance based criteria that appropriately evaluate bitumen resistance to low temperature cracking. Furthermore, first results – the severity of low temperature cracking in 26 road sections and lowest asphalt surface temperatures determined on the basis of nearest road weather stations – are given in this paper.
Published Madrid : Foundation Eurasphalt, 2021
Type Conference paper
Language English
Publication date 2021