Stack loading-vibration water bag combined preloading test method

The invention discloses a preloading-vibration water bag combined preloading test method. The method comprises the following steps: laying a soil body in a model box and pre-solidifying the soil body; an ultrasonic water bag is vertically arranged in the pre-consolidated soil body, and a plurality of ultrasonic vibration exciters are vertically arranged in the ultrasonic water bag at intervals; an annular loading plate is laid on the upper surface of the soil body, and an annular static pressure water bag is arranged on the annular loading plate so as to apply a vertical static load to the soil body; and the ultrasonic vibration exciter in the ultrasonic water bag is controlled to conduct ultrasonic vibration excitation so as to compact the soil body, and the soil body is made to settle. The combined preloading test method has the advantages that a preloading mode and a vibration mode are combined for use in the combined preloading test, compared with a method of preloading on the surface of a foundation only