Fracture toughness of colored slurry seal at low temperatures and different loading Modes: Comparative study with warm and hot mix asphalt materials

Abstract

Sustainable pavement, including colored slurry seal, was treated by crack growth under different traffic loads and temperatures. The current research examined colored slurry seals' fracture toughness at various temperatures under mixed modes I/II and I/III. Three-point bend fixtures were used to prepare edge-notched disk bend (ENDB) disk specimens with edge cracks along one side of the specimens. Then, different temperatures and complete range mode mixity, including I/II and I/III, were used to determine fracture toughness data as well as the critical stress-intensity factor. Results indicated that the samples' fracture resistance initially declined followed by an increment by an increment in the shear load in I/II mixed mode. From pure mode I to III, colored mixture resistances decreased with crack growth by raising mode III fraction at the crack tip. Moreover, lower temperatures led to better fracture performance between mixtures, especially at-20 degrees C. Mixtures' fracture performance was positively influenced by temperature reduction due to bitumen strength characteristics. Comparison of fracture envelopes of cold mix asphalts (CMAs) in I/II and I/III mode mixities with other types of asphalt concrete, such as warm and hot mix asphalt (WMA and HMA), showed higher susceptibility of CMA mixture to cracking failure mode, making it noticeably weaker than WMA and HMA mixtures.