Strength of Coarse-Grained Soil Stabilized by Poly (Vinyl Alcohol) Solution and Silica Fume under Wet–Dry Cycles

Abstract

To investigate an environmentally benign stabilizer for coarse-grained soil in southeast Tibet, poly (vinyl alcohol) (PVA) and silica fume were used to improve the geotechnical properties of coarse-grained soil. Unconfined compressive strength (UCS) and wet–dry cycle tests were conducted on prepared samples to evaluate the effect of the additive content and curing age on the strength and durability of coarse-grained soil. The results reveal that the UCS of the samples increased with the additive content of PVA solution and the curing age. The optimal value for the additive content of PVA solution and the curing age is 12% and 7 days, respectively. With the optimal PVA solution content, the PVA solution combined with silica fume stabilizer exhibited better reinforcement compared with pristine PVA. The UCS of the samples stabilized by PVA solution and silica fume increased depending on the curing age, and plateaued after 14 days. Samples with 12% PVA solution and 6% silica fume achieved a satisfactory UCS of 1543.17 kPa after curing for 28 days. As the number of wet–dry cycles increased, the UCS of the samples stabilized by the PVA solution and silica fume exhibited an upward trend during the first three wet–dry cycles, owing to the filling of pores by the gel produced by the silica fume, but began to decline as the number of wet–dry cycles increased. All samples retained a high UCS value after 10 wet-dry cycles compared with the samples that were not subjected to wet–dry cycles.

Durability Enhancement Effect of Silica Fume on the Bond Behavior of Concrete–PCM Composites under Environmental Conditions

“…The strengthened members are frequently located in harmful media and severe environments in the service life stage, causing early degradation and performance deterioration [31]. The durability issue under environmental conditions considering monolithic samples has been observed via experimental investigation in many previous studies [32][33][34][35][36][37]. In the technical literature, few studies have also been found that observed the durability issue on composite (repaired) samples under a freeze-thaw cycle [38][39][40], elevated temperature [41][42][43][44][45], etc.…”

Preparation, Structure and Characterization of Polymer/Cement Composites

“…Polymers are long-chain molecules that can improve the physical and chemical properties of soil, such as its strength, stability and water retention capacity. Zhao et al used Poly (Vinyl Alcohol) Solution and Silica Fume to enhance the strength of coarse-grained soil [9]. Sodium carboxymethyl cellulose (CMC) can improve the production capacity of saline-alkali soil [10].…”