Inversed construction method for adding basement in existing building

The invention discloses an inversed construction method for adding a basement in the existing building. The method includes that drilling pressure grouting piles and a bearing table are arranged on the periphery of the original foundation bearing table according to the design parameters of the original building, the drilling pressure grouting piles and the bearing table are utilized to support an upper structure frame stressed column, the bearing table is expanded to achieve foundation support replacement in the way that the upper frame column load can be borne effectively, then soil excavation is conducted to the design base elevation, an extrusion sleeve is connected with the drilling pressure grouting pile group, the high strength grouting material is utilized to pour wall columns formed by the newly added design pile and the frame column, then construction of base layers, water resistance, base plates and the like is conducted, and the frame column is connected with the foundation base plate in an inversed downwards mode. The existing building type and use functions on the ground are maintained, inversed basement layer adding and construction are performed simultaneously, the construction duration is short, the construction is independent, the cost is low and the effect of protecting environment is achieved. The method is especially applicable to multi-layer frame buildings, engineering with the upper building structure style not changed and the engineering with the basement requiring inversed layer adding.