Pit bottom cement soil composite inner support supporting structure of soft soil foundation pit

The invention provides a pit bottom cement-soil composite inner support supporting structure of a soft soil foundation pit. The pit bottom cement-soil composite inner support supporting structure comprises the foundation pit, a pit bottom cement-soil composite inner support part, a vertical support part and an inner support part above the pit bottom. According to the cement-soil composite inner supporting structure arranged at the bottom of the foundation pit, cement-soil piles are arranged at the bottom of the foundation pit in the form of one or two combinations or more than two combination structures of annular supporting, oval supporting, diagonal supporting and orthogonal supporting, and the cement-soil piles are in lap joint with one another to form a cement-soil whole; the whole cemented soil and the unreinforced soil body are coupled to form the pit bottom cemented soil composite inner supporting part, the pit bottom cemented soil composite inner supporting part makes contact with the vertical support