Pre-supporting and fixing device for bridge construction

The invention relates to the technical field of bridge construction equipment, and discloses a pre-supporting fixing device for bridge construction, which comprises a mounting seat and a supporting base, fastening devices are movably mounted at the top end of the mounting seat in a rectangular array manner, a stabilizing part is fixedly mounted at the top end of the supporting base, and a reinforcing assembly is movably mounted at the top end of the stabilizing part. Supporting columns are movably installed in the middles of inner cavities of the reinforcing assemblies and the stabilizing pieces, fixing mechanisms are fixedly installed at the top ends of the supporting columns, supporting mechanisms are fixedly installed at the top ends of the fixing mechanisms, supporting steel plates are fixedly installed at the top ends of the supporting mechanisms, and connecting plates are fixedly connected to the outer surfaces of the stabilizing pieces; the bridge is supported through the fixing mechanism and the suppo