## 5 Conclusions  
The development pattern of the clogging zone, along with the dewatering and consolidation capacities of the lime-flocculated slurry, APAM-flocculated slurry, dual-use PAC and APAM-flocculated slurry, and untreated slurry, were investigated using vacuum preloading tests combined with the PIV technique. The following conclusions can be drawn from this study:  
1. Severe clogging occurred in the untreated slurry, which hindered vacuum pressure transmission and reduced dewatering efficiency. Flocculation treatment improved the pore water pressure dissipation rate and dewatering performance of the slurry. Among the tested flocculants, the lime-flocculated slurry exhibited the fastest pore water pressure dissipation rate, while the dual use of PAC and APAM-flocculated slurry achieved the largest water discharge volume. In contrast, APAM flocculation treatment had a limited effect on improving the dewaterability of the slurry. 2. Line flocculation treatment significantly enhanced the vane shear strength of the slurry after vacuum preloading, whereas organic polymer flocculants had a relatively minor effect. 3. The horizontal strain near the PVD in the untreated slurry was high, indicating the presence of a dense clogging zone. Flocculation treatment effectively reduced clogging, with lime treatment showing the strongest mitigation effect, while APAM exhibited a relatively weaker impact. 4. This study proposes the development pattern of the clogging zone in flocculated slurry and elucidates the mechanisms through which flocculation treatments influence slurry clogging. The findings of this research can provide a theoretical basis for the selection of flocculants and the arrangement of PVDs in large-scale land reclamation and dredged slurry treatment projects. **Author Contributions:** Resources, Z.Y. ; Data curation, J.L. ; Writing--original draft, J.L. ; Writing--review & editing, X.Z. and S.X. All authors have read and agreed to the published version of the manuscript. **Funding:** This research was funded by National Natural Science Foundation of China (Grant No. 52108352) and the Zhejiang Provincial Natural Science Foundation (Grant No. LQ22E080020). **Data Availability Statement:** The datasets generated during and/or analyzed during the current study are available from the corresponding author upon reasonable request. **Acknowledgments:** This work was supported by College of Civil Engineering of Zhejiang University of technology The authors express their sincere gratitude for the experimental platform provided. Figure 13: The permeability coefficient of slurry in the clogging zone. Conflicts of Interest: Author [PERSON] was employed by the company Fangyuan Construction Group, the remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. +++ ==WARNING: Truncated because of repetitions==  
++  
* [PERSON] (2024) [PERSON] Enhanced consolidation and removal of accumulated flocculants in dredged soil via leaching with vacuum preloading. _Environ. Geochem. Health_**2024**, _46. early access._ [CrossRef]
* [PERSON] et al. (2023) [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON] Consolidation characteristics of high-water-content slurries improved by flocculation-enhanced surcharge (vacuum) preloading method. _Front. Mater._**2023**, _10_, 1166551. [CrossRef]
* [PERSON] et al. (2020) [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON] Application of flocculation combined with vacuum preloading to reduce river-dredged sludge. _Mar. Georesources Geotechnol._**2020**, _38_, 164-173. [CrossRef]
* [PERSON] et al. (2017) [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON] Combination of vacuum preloading and lime treatment for improvement of dredged fill. _Eng. Geol._**2017**, _227_, 149-158. [CrossRef]
* [PERSON] et al.