Study on shear resistance and crack resistance and toughening mechanism of fiber reinforced cement stabilized aeolian sand

Abstract

With an aim to elucidate the shear performance of the fiber reinforced cement stabilized aeolian sand aggregates, herein, glass fiber was uniformly incorporated into the cement stabilized aeolian sand composites. Unconsolidated undrained shear (UU) triaxial compression tests were carried out on specimens under different coupling effects, and the structural performance was improved and control tests were carried out. The mechanism of fiber crack resistance and toughening was analyzed at a micro level through SEM based on the fiber structure performance degradation control technology. The results showed that the fiber can effectively improve the failure strength of the cement-stabilized aeolian sand. The fiber added in cement-stabilized Aeolian sand had an optimal reinforcement ratio and length of 2.4 ‰ and 12 mm, respectively. The incorporation of fiber can significantly improve the overall stability of the blend material and alleviate the strength attenuation caused by the freeze–thaw cycle. As a deformation aggregate with continuous distribution defects, the fiber inhibits the initiation and propagation of cracks during the loading process of the specimen. The crack resistance effect is generated in the blend system and runs through the whole process before and after the loading, which eases the stress concentration at the tip of the crack. When the comprehensive amount of stress and strain reaches a certain critical value, the crack becomes unstable and expands. The research results can provide a reference for theoretical research and engineering practice of glass fiber reinforced cement curing aeolian sand.