Square tunnel profiling tunneling device for model test based on Reuleaux triangle principle

The invention discloses a square tunnel profiling tunneling device for a model test based on the Reuleaux triangle principle, and relates to the technical field of geotechnical engineering model tests.The square tunnel profiling tunneling device comprises a circular cutterhead, a center shaft, a side hole shaft, a Reuleaux triangle type rear cutterhead and a driving device, the round cutter head is arranged on the cutter head frame through a center shaft, the four reuleaux triangle type rear cutter heads are distributed behind the round cutter head in two rows in a staggered mode and arranged on the cutter head frame through side hole shafts, and the two reuleaux triangle type rear cutter heads in the front row are located on the upper right portion and the lower left portion of the cross section. The two reuleaux triangle rear cutterheads in the rear row are located on the upper left portion and the lower right portion of the cross section, and it is guaranteed that rotation of the two reuleaux triangle rear