Impact of Freezing and Thawing Cycles on Mechanical Performance of Carbon Fiber-Reinforced Cement-Stabilized Sand

In civil engineering, natural soils often lack the strength required for intended loads. Soil improvement techniques, such asusing cement and fibers, are employed to bolster mechanical properties for engineering structures. This study evaluates theefficacy of cement-stabilized sand reinforced with carbon fibers under freezing and thawing cycles. Key variablesinvestigated include cement and carbon fiber content, curing periods, and freeze-thaw cycles. Results show significantenhancements in unconfined compressive strength (UCS) with the addition of cement and carbon fibers. For instance,specimens with ۱۰% cement and ۲% carbon fiber achieved UCS values of up to ۱۷۱۷ kPa, ۱۵۲۱ kPa, and ۱۳۴۷ kPa undervarying freeze-thaw cycles at ۲۸ days. This combination also reduces crack formation by increasing strain at failure points.Specimens with ۲% carbon fibers and ۱۰% cement exhibited the highest failure strains under freeze-thaw cycles. However,increasing freeze-thaw cycles led to decreased UCS, although carbon fiber-reinforced specimens showed more resilience.The study highlights the efficacy of combining carbon fibers and cement for reinforcing sandy soil under freeze-thawconditions. Cement enhances UCS during stabilization, while carbon fibers improve strain at failure, enhancing soildeformability and mitigating failure mechanisms. This research provides insights into optimizing soil stabilization methodsfor civil engineering projects in challenging environmental conditions.

Keywords:

Sand , Freeze-Thaw Cycles , Soil Stabilization , Carbon Fibers , Cement