A study of the distribution ratio for combined spore-anchor supporting of unstable rocks based on FLAC3D

For the question of distribution ratio for combined spore-anchor supporting of unstable rock engineering, taking the unstable rock W32 in Shouli Mountain, Wanzhou City, this paper carried out the simulation study on the distribution ratio for combined spore-anchor supporting by means of monitoring displacement. It can be concluded that stability coefficient, displacement cloud and displacement gradients of monitoring points of unstable rock W32 indicated its instability, which was controlled by bedding surface and unloading plane; The maximum displacement at 500 kN of supporting spore reduced by 87.2% compared with no supporting, meanwhile, the maximum displacement at 500 kN of anchor reduced by 84.0% compared with no supporting, thus, supporting spore and rock anchor both nicely supported the stability of unstable rock. However, the supporting spore could lose its advantage of controlling displacement, but rock anchor could give play to its advantage of controlling displacement. The maximum displacement at 500 kN of conbined spore-anchor reduced by mora than 95% compared with no supporting, which indicated better supporting effect than that of the single supporting spore or rock anchor. Simultaneously, this paper analyzed that the best distribution ratio of conbined spore-anchor was 6:4 based on monitoring displacement.