Abstract: To promote thereutilization of soda residue (SR),SR modified clay stabilized by lime to form a Lime-Soda Residue Stabilized Soil (LSRSS),preparing the subgrade filler.Accordingly,Unconfined Compressive Strength (UCS),California Bearing Ratio (CBR),and Resilient Modulus (MR) tests were conducted to explore the impact of compaction degree and water content on the mechanical properties of LSRSS and to establish the correlations among UCS,CBR,and MR.Finally,LSRSS was applied to actual subgrade engineering via the construction of test sections.The results show that the UCS,CBR,and MR values of LSRSS all increase with the compaction degree increase,while first increasing and then decreasing with the increase in water content.The optimal mechanical properties do not correspond to the optimal water content of 23% but to a compaction water content (CWC) of 27%,which is more suitable for practical applications in the LSRSS subgrade.The correlation between UCS,CBR,and MR of LSRSS is significant,and the R² is greater than 0.80.The LSRSS subgrade using CWC exhibits good field road performance,with UCS,CBR,and MR values of 0.85MPa,86.5%,and 135.7MPa,respectively,meeting specification requirements.The establishment of field and laboratory test results and mechanical property correlations provides data support for the road performance of LSRSS as a subgrade filler,which is significant for its promotion and application.