| dc.description.abstract | In this paper, the strength, ductility and microstructure behavior of cement-treated silt with polypropylene fiber was studied by a host of experimental studies. The influence of fiber content (the weight of dry soil was 0.75%, 1.0%, 1.25%, 1.5%, 1.75% and 2.0%), curing time (7, 14 and 28 days) and freeze–thaw cycles (3, 6, 9, 15 and 30) on the unconfined compressive strength (UCS), post-peak stress ratio Rps, resilient modulus MR and mass loss ratio Rml of reinforced silt with 12% cement was discussed in detail. Test results indicated that the addition of polypropylene fiber can improve the UCS of reinforced specimen and the optimal fiber content is 1.75%. Under freeze–thaw cycles, the inclusion of clay with fiber content ranging from 0.75 to 2.0% can increase the UCS. The addition of polypropylene fibers can significantly enhance the post-peak stress ratio of the specimens. The mass loss ratio increased with the number of freeze–thaw cycles. The soil specimens free of fiber were completely destroyed after nine freeze–thaw cycles, while the mass loss rate of the soil specimens with fiber were less than 8%. An empirical model was established to predict the peak value of UCS considering the effect of freeze–thaw cycle and fiber content using logarithmic and quadratic polynomial function, respectively. The predicted results are in good agreement with the tested results. The microstructural study shows that the spatial three-dimensional network between fibers and soil particles is conducive to increase the shear strength of the fiber-reinforced silt. The results indicate that the application of polypropylene fiber in silt reinforcement is an effective way to reuse resources. | en_US |
