The invention discloses a multifunctional vacuum preloading consolidation experiment apparatus which employs a small-scale test model for simulating vacuum preloading and heaped loading tests. The apparatus comprises a vacuum preloading consolidation chamber, a top plate, a pedestal, an axial-direction clamping member, a plastic-drainage-belt fixing frame, vacuumizing equipment, supercharging and pressure-stabilizing equipment, a vertical drainage system, a drained-water collection and drained-water volume measure system, a thick-layer preloading membrane, a settlement displacement measure system and an air pressure measure system. The apparatus is capable of simulating closed type vacuum preloading test, supercharged type vacuum preloading test, positive-negative pressure circulating type vacuum preloading test, heaped preloading test and other tests established under the cases of controllable deformation of the drainage belt, completely satisfies indoor experiment demands under different conditions, practices design ideas of low cost and multiple functions in a real sense, and possesses multiple advantages such as simple structure, operation convenience, strong visibility, applicability to multiple vacuum preloading test research, and the like. The invention also provides multiple methods for performing closed type vacuum preloading experiments by employing the multifunctional vacuum preloading consolidation experiment apparatus.