MechanicalProperties and Frost Resistance of Cement-Modified Soil Treated withSucrose-NaCl Composite for Subgrades in Cold-Region Metallurgical Plants

Subgrade infrastructure in metallurgical plants located in cold regions is highly susceptible to deterioration from freeze-thaw (F-T) cycles and performance loss due to delays between mixing and compaction. This study investigates a composite chemical admixture of sucrose and sodium chloride (NaCl) to enhance cement-stabilized soils for subgrade applications. Laboratory testing included standard Proctor compaction to determine density configurations, unconfined compressive strength (UCS) testing under simulated operational delay periods (0–3) h, and strict freeze-thaw (F-T) cyclic evaluations for durability profiling. Results identified an optimal dosage of 0.08 % sucrose and 1.0 % NaCl (by cement mass). This composite mix achieved a maximum dry density of 2.136 g·cm⁻³ (97.96 % of the non-admixed control), increased 28-day UCS by 12.88 % to 3.33 MPa, and exhibited minimal strength loss after five freeze-thaw cycles. Sucrose effectively preserved workability to mitigate delay effects, while NaCl concurrently enhanced strength and frost resistance. The proposed admixture system provides a practical solution for constructing durable subgrades in cold-climate metallurgical facilities.