Tool type supporting system capable of automatically adjusting axial force for foundation pit

The invention discloses a tool type supporting system capable of automatically adjusting axial force for a foundation pit, and aims to provide the tool type supporting system capable of automatically adjusting the axial force for the foundation pit, which can timely adjust prestress applied to a profile steel supporting beam when the foundation pit displaces so as to eliminate deformation displacement of the foundation pit and keep the foundation pit in a stable state. The structure comprises a foundation pit enclosure wall; enclosing purlin beams; the profile steel supporting beams are supported between the purlin beams; the self-adjusting type prestress device provides prestress for the profile steel supporting beams so that the profile steel supporting beams can be supported between the purlin beams, and the self-adjusting type prestress device comprises an electric hydraulic jack and a foundation pit deformation displacement monitor. The foundation pit deformation displacement monitor is used for monitori