Strength behavior of dredged mud slurry treated jointly by cement, flocculant and vacuum preloading

Application of the flocculation–solidification combined method (FSCM) is a rational option for treatment and recycling of dredged mud slurry at extra high water content (EHW-MS). However, FSCM tends to show some limitations when the treated EHW-MS is recycled as filling material with high requirement on mechanical properties. Via introducing the vacuum preloading (VP) and fiber reinforcement (FR) into FSCM, two novel procedures (i.e., VP-FSCM and VP-FR-FSCM) are newly developed in this study for more efficient treatment and recycling of EHW-MS. Five groups of laboratory experiments are conducted to verify the superiority of VP-FSCM and VP-FR-FSCM over FSCM in EHW-MS treatment and to characterize the effect of some key factors on the treatment efficiency of VP-FSCM and VP-FR-FSCM. The fundamental mechanisms of VP-FSCM and VP-FR-FSCM are also discussed based on the X-ray diffraction spectrums and the scanning electron microscope images. The results indicate that VP-FSCM and VP-FR-FSCM show significant superiority over FSCM in treatment and recycling of EHW-MS, and the strength of VP-FSCM or VP-FR-FSCM treated EHW-MS is at least 2.36 times larger than that of FSCM treated EHW-MS.