观音阁水库大坝左岸句1～5岸被坝段应落于倾角为48～63°的陡坡上．在左岸岸坡坝段的设计中，吸取了国外经验，特左岸几个坝段全部王于开挖成陡坡的基岩面上．计算中采用高、陡岸被坝段平面计算方法──极限强反法的基本原理，并将计算结果与三维地质力学模型试验和三维有限元计算结果进行验证对比．结果表明，极限强度法计算结果正确，计算程序可靠，计算设计合理，可供陡岸被坝段设计参考． Guanyinge reservoir dam left bank sentence 1 to 5 dam should fall on the slope of 48 ~ 63 ° steep slope. In the design of the left bank slope dam section, it draws on the experience of foreign countries. All of the special dam sections on the left bank are all on the bedrock surface of steep slope excavation. In the calculation, the basic principle of the plane-to-plane method of extreme and strong anti-slope is adopted, and the calculation results are compared with the 3D geomechanical model test and the three-dimensional finite element calculation results. The results show that the ultimate strength method is correct, the calculation procedure is reliable, the calculation and design is reasonable, and the steep bank can be referenced by the dam section design.