中文摘要：

探讨了三峡库区滑坡治理滑面倾斜时抗滑桩桩前岩土体弹塑性区临界高度的计算模式。介绍了常用的确定抗滑桩嵌岩深度的工程地质法和强度控制法，剖析了抗滑桩设计的弹性理论和弹塑性理论，利用空间楔形体极限平衡理论，得出了滑面倾斜时桩前岩土体弹塑性区的临界高度计算公式，并且讨论了弹塑性区临界高度与滑面倾斜：龟度及岩体的强度参数之间的关系。以三峡库区万州区某滑坡为例，计算了桩前弹塑性区的临界高度，并总结出临界高度与滑面倾角及岩体的黏聚力呈指数分布关系，与岩体的抗力及岩体的内摩擦角呈线性分布关系的规律。根据这些规律可以对抗滑桩嵌岩深度进行修正，并适当地控制抗滑桩嵌岩段岩土体弹塑性区临界高度。

英文摘要：

In light of geo-hazard control in the reservoir area of Three Gorges Project in China, the calculation of critical height of rock-soil elastoplastic area before anti-slide pile on declining sliding surface is carried out with limit equilibrium theory of space wedge block. Firstly, the usual methods of calculating rock-socketed length of anti-slide pile are described, such as engineering geological method and strength controlling method. Secondly, two theories, elastic and elastoplastic theories used to calculating rock-socketed length are compared. Thirdly, the critical height of elastoplastic area of mass before piles is put forword when the slipping surface is declining; meanwhile, the relationships among critical height and angle of sliding surface, resist force of rock and strength parameters of rock are discussed. Finally, taking a project in Wanzhou city of Three Gorges Resevior area for example, the critical elastoplastic height of rock-soil before anti-slide is given; and rules have been found that the critical height h shows a exponential distribution along sliding surface angle θ and cohesion c of rock, and linearly distribution along the resist force o and friction angle φof rock .According to these rules, we can give proper correction to anti-slide pile＇s rock-socketed length and critical height of elastoplastic area of rock-soil before anti-slide pile.