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

Understanding the dynamic resilient modulus (MR) 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 MR were analyzed by dynamic triaxial tests, and the prediction model for MR of CMSRM was studied also. The results show that the MR 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 MR of CMSRM increases at first and decreases later. Grey correlation analysis showed that the MR 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 MR was proposed. The research can provide useful information for the application of carbonaceous mudstone embankment in humid-heat regions.