Research on the dynamic resilience characteristics of carbonaceous mudstone soil-rock mixture under wet-dry cycles

Understanding the dynamic resilient modulus (M_R) of a recycled carbonaceous mudstone soil-rock mixture (CMSRM) embankment under wet-dry cycles can provide a basis for CMSRM embankment design and evaluation. The effects of the stress states, rock contents, and wet-dry cycles on M_R were analyzed by dynamic triaxial tests, and the prediction model for M_R of CMSRM was studied also. The results show that the M_R of CMSRM is negatively correlated with the deviation stress and positively correlated with the minimum bulk stress, with significant stress-dependent characteristics. With the increase in rock content, the M_R of CMSRM increases at first and decreases later. Grey correlation analysis showed that the M_R of the CMSRM is affected by the rock content, minimum bulk stress, wet-dry cycles, and deviator stress in order of priority. Considering the comprehensive effects of stress states, wet-dry cycles and particle gradation, a model predicting the M_R was proposed. The research can provide useful information for the application of carbonaceous mudstone embankment in humid-heat regions.