Crack opening variable-angle strengthening test experimental device

The utility model discloses a crack opening degree variable angle strengthening test experimental device. The device comprises a sample mold, similar materials and airbags, the sample mold is a hollowsquare box with an opening in the upper end; the air bag is placed in the sample mold; similar materials are poured into the sample mold to fix the air bag; airbag in oblate ball shape, a pressure-bearing hose for inflating and deflating the air bag is arranged at the upper end of the air bag; four bearing holes are further formed in the outer wall of the air bag; the four bearing holes correspond to each other in pairs and are located in the four side faces of the centroid of the air bag, a fine line is fixed to each bearing hole, four restraining holes are formed in the sample mold, two restraining holes are located in the bottom of the sample mold, the other two restraining holes are located in the outer wall of the sample mold, and the fine lines penetrate through the restraining holes and are used for contro