Based on Barron’s equal strain consolidation theory

the consolidation governing equation of sand-drained foundation under vacuum combined surcharge preloading is derived and a general analytical solution is obtained

which considers the vacuum loading process

the time-dependent surcharge loading

the characteristics of the vacuum pressure decreasing along the depth and radial direction

and the well resistance of vertical drains and the vertical flow. The correctness of the analytical solution proposed in this paper is verified by comparing the degenerate analytical solution with the existing analytical solution and the finite difference solution. Based on the analytical solution

the consolidation behaviors of sand-drained foundation are analyzed. The analysis shows that the consolidation rate of sand-drained foundation is accelerated with the increase of vacuum loading factor ?. However

when ? increases to a certain extent

the influence of vacuum loading process on the consolidation rate of sand-drained foundation can be ignored. The consolidation rate of sand-drained foundation decreases with the increase of vacuum pressure attenuation coefficient k1 and k2. The consolidation rate of sand-drained foundation decreases with the increase of vacuum pressure p0 and increases with the increase of final surcharge loading qu. With the increase of loading time Th1

the consolidation rate of sand-drained foundation decreases gradually

and the consolidation rate is the largest under instantaneous surcharge loading.