Construction technology for large-depth semi-reverse excavation and steel pipe column inner supporting structure

The invention relates to a construction process for large-depth semi-reverse excavation and a steel pipe column inner supporting structure, and the construction process comprises the following steps: S1, horizontally arranging first profile steel between two adjacent steel pipe columns on one side of a foundation pit, and excavating a soil body, located below a negative second structural layer, on the side, after excavation is conducted to the bottom face, a negative second structure layer is poured upwards to obtain a first beam body; s2, second profile steel is horizontally arranged between every two adjacent steel pipe columns on the other side of the foundation pit, a soil body, located below the negative second structural layer, on the side is excavated, and after excavation is conducted to the bottom face, the negative second structural layer is poured upwards to obtain a second beam body; and S3, third profile steel is horizontally arranged between every two adjacent steel pipe columns in the middle of