Reinforcement Effect of the Stepped-Alternating Vacuum Preloading Method on Dredged Fills
Publication: International Journal of Geomechanics
Volume 24, Issue 2
Abstract
Dredged fills have been widely used as a filling material to meet the demand for land resources during land reclamation in coastal areas. When the conventional vacuum preloading (CVP) method is used to reinforce dredged fill foundations, clogging and accumulation of a dense silt layer significantly reduce the lateral soil permeability of the soil surrounding prefabricated vertical drains (PVDs), leading to a poor reinforcement effect. To address these issues, this paper presents a laboratory model study to evaluate the reinforcement effect of a new method, the stepped-alternating vacuum preloading method (SAVP), in comparison to the CVP method. A series of laboratory model tests were conducted to compare the results of the new SAVP method and the CVP method. The model tests used water discharge, discharge rate, and surface settlement to compare both methods. Additionally, vane shear strength and moisture content were measured after reinforcement. This study evaluates the performance of the SAVP method and proposes an optimal preloading pattern that demonstrates best performance in delaying clogging formation and alleviating the accumulation of a dense silt layer on the surface of the PVDs.
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Data Availability Statement
All data, models, and codes generated or used during the study appear in the published article.
Acknowledgments
The authors would like to acknowledge the financial support of the National Natural Science Foundation of China (No. 52078334).
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Information & Authors
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Published In
International Journal of Geomechanics
Volume 24 • Issue 2 • February 2024
Copyright
© 2023 American Society of Civil Engineers.
History
Received: Feb 27, 2023
Accepted: Jul 16, 2023
Published online: Nov 22, 2023
Published in print: Feb 1, 2024
Discussion open until: Apr 22, 2024
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