Application of block element method to excavation and reinforcement analysis of Longtan slope

The right abutment slope of Longtan project is almost 300 m high, and the geological condition is complicated. The stability analysis aiming at the given blocks indicates that the local stability of the slope, where the small block and the middle block are shaped, is not sufficient without reinforcement during the excavation. By the elasto-viscoplastic block element method (BEM), the excavation and reinforcement analysis of Longtan slope is conducted, and the complicated excavation procedure and reinforcement measures are simulated effectively. The calculation results indicate that the characteristics of the displacement increments of each excavated step and the distributions of the yield zones on the discontinuities under various work conditions are reasonable, the reinforcement measures control the deformation of excavation effectively, and compared with no reinforcement condition, the stability safety factors of the given blocks are enhanced to a certain extent under various work conditions. The study shows that BEM has merits of efficiency, conveniency and practicability for practical rock engineering.