Abstract: A structure for supporting a foundation pit based on a steel edge-arch structure, including: an enclosing purlin beam, the steel edge-arch structure, a plurality of support beams and a plurality of triangular supports. The support beams are located at an inner side of the enclosing purlin beam. The triangular supports are arranged on the enclosing purlin beam. End portions of the support beams are supported on the enclosing purlin beam through the triangular supports, and abutted on side edges of the triangular supports. The steel edge-arch structure is located between two adjacent triangular supports. The steel edge-arch structure includes two first haunched members and a bracing beam provided therebetween.

Abstract: A haunched component-based steel support structure for a foundation pit, including an enclosing purlin beam, a support beam located on an inner side of the enclosing purlin beam, and a triangular support arranged on the enclosing purlin beam. A first edge of the triangular support is fixedly arranged on the enclosing purlin beam. An end of the support beam abuts against a second edge of the triangular support to be supported on the enclosing purlin beam, and a haunched component is arranged between the enclosing purlin beam and a third edge of the triangular support. A first side of the haunched component is connected to the third edge of the triangular support, and a second side of the haunched component is connected to the enclosing purlin beam.