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Traditional slope protection methods face many challenges when applied to carbonaceous mudstone slopes. The objective of this study was to develop a novel protection method based on vegetation concrete with carbonaceous mudstone aggregates (VCCMA) and then examine its performance and underlying protective mechanism. Hence, physical model tests were performed on highly-weathered carbonaceous mudstone slopes under wet-dry cycles considering three different protection cases, i.e., no protection, protection using porous concrete with carbonaceous mudstone aggregates (PCCMA) and protection using VCCMA. The erosion characteristics, volumetric moisture contents, and slope deformations of the slopes were measured. Finally, the performances and underlying mechanisms of the protection methods for slopes were compared. The results demonstrate that the unprotected slope, the PCCMA-protected slope, and the VCCMA-protected slope were descending according to the erosion damage, the particle loss amount, and the deformation during five wet-dry cycles. Among the two protected cases, the VCCMA exhibits better erosion coefficient, water retention capacity and disintegration resistance of the slope. The runoff volume depends on the protection method and shows a weaker correlation with wet-dry cycles. In the case of PCCMA protection, the protection effects come from self-weight consolidation, water interception, and integral protection structure. The VCCMA protection case incorporates additional protective mechanisms, including soil moisture regulation by leaf transpiration, resistance to rainfall splashing and scouring by stems and leaves, and soil reinforcement and anchoring by roots. Therefore, the VCCMA holds significant potential for effectively protecting problematic slopes. These findings provide valuable guidance for the protection of highly-weathered carbonaceous mudstone slopes.

来源平台：BULLETIN OF ENGINEERING GEOLOGY AND THE ENVIRONMENT