Abstract: At present, the arching characteristics of soft rock mass are rarely studied. The research in the distribution pattern of the arch effect between the rock mass and anti-slide piles, the stress distribution characteristics of rock body around piles after the arching and the reasonable pile spacing is not thorough enough. The effect of the structural plane development characteristics on the anti-slip effect of rock mass is studied in this paper by the numerical simulation. The results show that, when the sliding body is in soil and in mudstone, the arch formation between anti-slide piles is obvious; when the sliding body is in sandstone, there is almost no arch formation; when the inclination of the structural plane increases, the rock arch effect is increasing. The research results are expected to have a significant progress in the development of rock slope stability on the structural surface of anti-slide pile, which can provide an important theoretical support for the optimal design of anti-slide pile.

Key words: lithology, structural plane, occurrence, arch formation of rock mass