Abstract
Asphalt pavements suffer from and are damaged by the effects of repetitive freezing-and-thawing cycles in cold and snowy areas such as Hokkaido. It may be much more important believed to select the proper kinds of binders, mixtures and mix design to prevent such damages.
This paper consists of (1) a rapid freezing-and-thawing testing apparatus and method (Figs. 1, 3), (2) evaluation of modified asphalt mixtures including straight, catalytic semibown, and rubberized asphalts (Table 1) by Marshall stability and Ravelling abrasion tests, (3) test results and discussion, and (4) conclusions.
The following conclusions are obtained from the laboratory tests:
(a) The void ratios of modified asphalt mixtures of asphalt mortar and fine graded gapped asphalt concrete (Fig. 4, Table 3) increase in proportion to the action of repetitive freezing-and-thawing cycles and increase in relation to the void ratio of the non-cycled Marshall specimens involved (Figs. 5, 6).
(b) Properties in Marshall stability and Ravelling abrasion are affected by freezing-and-thawing cycles and their effects may fluctuate in relation to the kinds of binders and mixtures and the void of ratios of non-cycled modified asphalt mixtures (Figs. 7, 8).
(c) Stability and abrasion of rubberized asphalt mixtures containing 8% SBR latex may not be affectep by freezing-and-thawing cycles as them of straight and semiblown asphalts (Fig. 9).
