The invention discloses a foundation pit inclined
support system and a foundation pit inner support construction method. The foundation pit inclined
support system comprises a side wall
enclosure structure of a foundation pit, a top beam connected with the side wall
enclosure structure, a steel
pipe inclined strut and a bracket, wherein the bracket is fixedly arranged on a foundation pit bottom plate, the steel
pipe inclined strut is arranged between the side wall
enclosure structure and the foundation pit bottom plate in an inclined strut mode, one end of the steel
pipe inclined strut is fixedly connected with the top beam, and the other end of the steel pipe inclined strut is fixedly connected with the bracket. The foundation pit inner support construction method is based on the foundation pit inclined
support system and comprises the following steps of (1) mounting a long type inclined strut; (2) excavating reserved soil and constructing a residual bottom plate; (3) mounting a short
type replacement support and removing the long type inclined strut; and (4) constructing a main body structure and removing the short type inclined strut. The foundation pit inclined support
system and the foundation pit inner support construction method have the advantages that supporting materials can be recycled, so that the supporting rigidity is increased; and the support construction period is short, the reserved soil excavation difficulty is reduced, the construction cost is reduced, and the construction safety is improved.