Abstract:After flocculation conditioning and chemical solidification, the initial bad engineering characteristics of high water content mud can be improved. If waste mud is to be recycled into embankment filler, it is bound to have certain requirements on the strength of the treated mud. In recent years, the authors have explored and proved that the vacuum preloading-flocculation-solidification combined method (VP-FSCM) can effectively treat mud slurry with high water content (> 300%) and transform it into embankment filler. This study has carried out a series of laboratory model tests, on the one hand, to explore the feasibility and high efficiency of VP-FSCM process for treating waste mud (water content is about 150~300%); On the other hand, to optimize the formulation (type and dosage, etc.) of VP-FSCM process in waste mud treatment. The test results show that: (1) The undrained shear strength of the waste mud treated by VP-FSCM after 28 days is 2.76 times that of the waste mud treated by flocculation-solidification combined method (FSCM), which proves the high efficiency and feasibility of VP-FSCM. (2) The results of dehydration / settlement characteristics and mechanical characteristics show that the best additives for treating waste mud by VP-FSCM process are cement (OPC), ground granulated blastfurnace slag (GGBS), quicklime (CaO) and polyacrylamide (PAM), and their optimal contents are 5%, 5%, 1.5% and 0.12% respectively. (3) Under the condition of the best additive type and dosage, the higher the vacuum pressure, the higher the strength of the treated waste mud and the lower the moisture content after curing.