Method for reconstructing damaged slab culvert structure system through section steel and corrugated steel combined underground excavation

The invention relates to a method for reconstructing a damaged slab culvert structure system through section steel and corrugated steel combined underground excavation. The method comprises the following steps that a damaged slab culvert unit bottom plate is reconstructed through section steel; reconstructing an original slab culvert structure unit section; and reconstructing the whole-section damaged slab culvert. The existing slab culvert is subjected to non-excavation repair by adopting an internally-assembled profile steel and corrugated steel combined structure, a plain concrete bottom plate of the slab culvert is transformed into a profile steel concrete bottom plate, the profile steel concrete bottom plate and a corrugated steel plate on the profile steel concrete bottom plate form an integral stress structure, and a slab culvert structure which cannot bear external water pressure load is reconstructed into a structural system capable of bearing internal and external pressure working conditions. Compar