Fully coupled large-strain radial consolidation analysis for dredged marine slurry treated by prefabricated vertical drain with vacuum and heat preloading

The use of prefabricated vertical drain (PVD) in conjunction with vacuum and heat preloading is an effective improvement approach for dredged marine slurry. Despite it being a typical large-strain thermal-hydro-mechanical (THM) problem, there is currently a lack of reliable large-strain analysis methods for this problem. This study therefore develops a large-strain radial consolidation model, considering a thermal elastoplastic constitutive model of soft clays, self-weight of dredged slurry, radial and vertical flows, nonlinear hydraulic conductivity, nonlinear compressibility during the consolidation process, heat conduction, and heat convection process. The modified alternative direction implicit (ADI) difference approach is used to solve the proposed model. The numerical algorithm is then verified by degraded verification with a well-established radial-large strain consolidation model. A laboratory experiment has been employed to show the effectiveness of the proposed model in predicting the consolidation behavior. A graphical user interface (GUI) has been programmed for potential users based on the proposed model and numerical algorithm. The results indicate that heat preloading improves the permeability of soil, resulting in a larger settlement of soil. Heat preloading serves as an effective method to enhance the efficiency of PVD.