Abstract: This paper studies the cracking resistance of crumb rubber-modified asphalt concrete (CRMAC) under variable temperature conditions in water conservancy engineering environment, based on the small beam bending test and the brittleness index of full stress-strain curves. The results show that at the optimum performance, the ratio of CRMAC cracking resistance is 80M at a crumb rubber dosage of 20%. Under low temperature conditions, the bending strength and peak strain of CRMAC are better than those of matrix asphalt concrete; the lower the temperature, the larger the brittleness index of asphalt concrete, and the more prone to cracking of the specimen. Adding crumb rubber reduces the brittleness index of matrix asphalt concrete and improves its cracking resistance; it also changes the stress state of matrix asphalt concrete at -10 ℃, and changes the stress-strain curve from brittle to plastic characteristics. This study provides new approaches for panel material selection.

Key words: crumb rubber, hydraulic asphalt concrete, variable temperature, brittleness index