Structural damage and shear performance degradation of fiber–lime–soil under freeze–thaw cycling

• Published in: Geotextiles and geomembranes Vol. 50; no. 5; pp. 845 - 857
• Main Authors: Wei, Li, Chai, Shouxi, Xue, Meiling, Wang, Pei, Li, Fang
• Format: Journal Article
• Language: English
• Published: Essex Elsevier Ltd 01.10.2022; Elsevier BV
• Subjects: Cycles; Fiber reinforced composites; Fiber reinforcement; Fiber soil; Freeze thaw cycles; Freeze–thaw cycling; Freezing; Friction; Internal friction; NMR; NMR test; Nuclear magnetic resonance; Performance degradation; Porosity; SEM test; Shear; Shear stress; Soil erosion; Soil freezing tests; Soil lime; Soil porosity; Soil structure; Strain rate; Structural damage; Triaxial compression test; Triaxial compression tests; Freeze–thaw cycling; SEM test; Fiber soil; NMR test; Triaxial compression test
• ISSN: 0266-1144; 1879-3584
• DOI: 10.1016/j.geotexmem.2022.04.005

The freeze–thaw cycling damages the soil structure, and the shear performance of soil are degraded. A series of tests on lime–soil(L–S) and fiber–lime–soil(F–L–S), including freeze–thaw test, the triaxial compression test, nuclear magnetic resonance (NMR) test and scanning electron microscope (SEM) test, were completed. The test results showed that fiber reinforcement changed the stress–strain behavior and failure pattern of soil. The cohesion and internal friction angle of soil gradually decreased with the increase of freeze–thaw cycles (F–T cycles). The pore radius and porosity of soil increased, while the micro pore volume decreased, and the small pore volume, medium pore volume and large pore volume increased, and the large pore volume had a little variation after 10 F–T cycles. The number of pores of F–L–S was less than L–S, demonstrating that the addition of fiber helped to reduce the pore volume. The interweaved fibers limited the development and the connection of cracks. By means of the spatial restraint effect of fiber on the soil and the friction action between fiber and soil, the shear performances and freeze–thaw durability of F–L–S better were than that of L–S. •The shear performances and freeze–thaw durability of soil were improved because of adding fiber.•The microstructure of the same sample was tested under freeze–thaw cycles by NMR test.•The effect of fiber reinforcement under freeze–thaw cycling was evaluated by triaxial compression test, NMR and SEM tests.