Abstract: In order to further study the interaction relationship between the concrete filled steel tube scaffold and the surrounding rock, this paper records the changes of the stress, deformation and failure of the roadway with the change of the external load by the means of similar physical model, and studies the law of the process. The experiment was first used to simulate the concrete filled steel tube scaffold filled with cement mortar slurry in the aluminum tube, which greatly reduced the relationship between the steel tube and the core concrete. The test shows that, first of all, the support of the concrete filled steel tube support is a passive closed type support form, and the displacement is produced at the first place, and the ratio of the vector span ratio of the 1/4 arc arch decreases and the load and deformation ability of the surrounding rock is reduced. When the displacement occurs after the displacement, the ratio of the 1/4 arc arch is increased. The load and deformability of the surrounding rock increase. The displacement of the first place usually occurs in the direction of the pressure of the weak rock and the surrounding rock, or the construction problem, and does not guarantee the complete fitting of the concrete filled steel tube support and the surrounding rock. Furthermore, the radial stress of the concrete filled steel tube is passively provided by the concrete filled steel tube, which greatly improves the ability of the surrounding rock to bear the load. It provides a theoretical basis for further study of the combined support and reasonable support section of concrete filled steel tube.