Abstract：Vacuum-surcharge combined preloading is a commonly used method for soft ground improvement. Aiming at developing a reasonable calculation method for evaluating foundation settlement process in engineering practice, a numerical model called VRCS1 to calculate the large-strain radial consolidation of saturated soft soils stabilized by the vacuum-surcharge combined preloading method was developed based on the piecewise-linear approach. The algorithms of VRCS1 model were deduced，and comparisons between the VRCS1 model with the existing small-strain analytical solution，large-strain numerical solution and large-scale laboratory experiments were conducted. It is shown that the VRCS1 model can accurately simulate the process of large-strain radial consolidation of saturated soft soils. Besides，compared with the existing large-strain solutions in the literature，VRCS1 model has a wider range of application due to considering a variety of complex factors involved in the radial consolidation process and adopting the piecewise-linear method to define the compressibility and permeability of soils. VRCS1 model was used to calculate the settlement of an embankment at Second Bangkok International Airport，Thailand，and good agreement between VRCS1 model calculations and field measurements was obtained.
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2019, Vol. 38 
