Fly Ash/Paraffin Composite Phase Change Material Used to Treat Thermal and Mechanical Properties of Expansive Soil in Cold Regions

Phase change materials (PCMs) can store large amounts of energy in latent heat and release it during phase changes, which could be used to improve the freeze-thaw performance soil. The composite material was prepared with paraffin as PCM 8% Class C fly ash (CFA) supporting material. Laboratory tests were conducted reveal influence (CFA-PCM) on thermal properties, volume changes mechanical properties expansive results show that failed establish a good improvement effect due leakage. CFA effectively adsorb materials, two have compatibility. CFA-PCM reduces strength attenuation soil, 8 wt.% is optimal content. turns down soil improves its stability. makes impact small pore structure damage macroscopic scale. In addition, CFA-8 treated has apparent advantages resisting repeated cycles, providing reference for actual engineering design.