Mechanical Behavior of Cement-Stabilized Silt with Rubber Fines and Buffings

Abstract

The engineering properties of cemented silt with rubber fines and rubber buffings mixtures are investigated using compaction, unconfined compression, direct shear, and freeze–thaw (FT) cycle tests. The rubber fines (20-mesh size, 80-mesh size), rubber buffings, and cement content in these specimens are equal to 2.5%, 5%, 7.5%, 10%, 12.5%, 15% and 3%, and 5% of dry weights, respectively. The maximum dry density of the modified soil is significantly reduced after adding the waste tire rubber. Furthermore, the addition of rubber fines is more evident in the decrease of maximum dry density compared with the inclusion of rubber buffings. The addition of rubber fines and rubber buffings improved shear strength, including cohesion and friction angles. The unconfined compressive strength of most specimens decreased after the tire rubber is added. However, cement hydration in the early curing stages is inhibited when rubber is added. As a result, the optimal dosage of the rubber buffings is 5%. The FT cycle tests indicated that the strength of the soil blended with the rubber buffings decreased after FT cycles, and the lowest value is found after the sixth cycle, and the specimen porosity increases with rubber buffings, and this effectively reduced the influence of water frost. In general, the modified soil had good FT resistance.