Study on Moisture Adjustment Factor for Resilient Modulus of Subgrade

Abstract:

Several types of subgrade soil were sampled,and resilient modulus of subgrade soil with different moisture were measured using UTM dynamic triaxial test symtems.The effect of moisture on resilient modulus was analyzed and parameter calibration was executed on Witczak model of moisture adjustment factor for resilient modulus,furthermore,the model of moisture adjustment for resilient modulus applicable to coarse and fine grained soil in China was established.The results indicate that moisture adjustment factor varies linearly with moisture difference value which is in the range of -20%～20%,and moisture adjustment factor is not affected significantly by moisture difference value which exceeds 20%.Using the established model,the moisture adjustment factors for different types of subgrade soil are recommended,which can be used to predict field resilient modulus of subgrade soil with real moisture content combined with resilient modulus test in laboratory.

Key words:resilient modulus of subgrade; moisture; adjustment factor; predictive model