Vacuum preloading device with sandbag cushion layer

A vacuum preloading device with a sandbag cushion layer comprises a vacuum pump, a longitudinal sandbag layer, a transverse sandbag layer, geotechnical cloth, a clay sealing layer, a polyethylene sealing film and a water-covering sealing layer. The longitudinal sandbag layer, the transverse sandbag layer, the geotechnical cloth, the clay sealing layer, the polyethylene sealing film and the water-covering sealing layer are sequentially laid on the soil surface from bottom to top. A plurality of vacuum tubes communicated with a vacuum pump are buried in sandbag gaps of the longitudinal sandbag layer, and a plurality of plastic drainage plates are fixedly inserted into the bottoms of sandbags of the longitudinal sandbag layer; the polyethylene sealing film is laid on the clay sealing layer and the upper surface of the film pressing groove in a sealed mode, and the upper surface of the polyethylene sealing film is provided with a water-covered sealing layer. According to the vacuum preloading device, the arrangem