深厚回填土嵌岩桩设计计算方法是回填区桩基工程建设的关键技术之一。因此，开展相关问题研究具有重要的理论与实际意义。首先，通过相似原理设计深厚回填土嵌岩桩竖向承载模型试验。重点研究回填土压实度、回填厚度、回填土-桩界面粗糙度特性、嵌岩深度对深厚回填土嵌岩桩承载特性的影响。其次，建立考虑回填土压实度、回填厚度、回填土-桩界面粗糙度特性等因素的PFC3D数值模型，深入探讨回填土-桩界面的摩阻力发挥、桩侧摩阻力和桩端阻力的大小、端阻荷载分担比及径向应力扩散等性状，揭示竖向荷载作用下深厚回填土嵌岩桩承载机理。在此基础上，引入突变理论原理，解决深厚回填土嵌岩桩体系位移发展模式、能量扩散边界、能量方程建立、突变失稳准则等关键问题，进而建立竖向荷载作用深厚回填土嵌岩桩承载力计算方法。最后，结合双曲线切线模量法和荷载传递法，提出深厚回填土嵌岩桩非线性沉降计算新方法，以期完善深厚回填土嵌岩桩设计计算理论。

The design method of rock-socketed piles in deep backfill is one of the key technologies for pile foundation engineering construction in backfill area.Therefore, it is of great theoretical and practical significance to carry out research on thistopic.Firstly, the model testsonvertical bearing capacity of rock-socketed piles in deep backfill is designed based on the similarity principle.Influence parameters including the backfill compaction, backfill thickness, the characteristics of backfill soil-pile interface roughness and the embedded depth of pile in rock are studied. Subsequently, considering the influence parameters, numerical models are established by the software PFC3D. Based on thenumerical results, the development of side friction of backfill soil-pile interface, the bearing ratio of pile side friction and tip resistance, and radial stress dispersion are analyzed to investigate the response ofrock-socketed piles in deep backfill under vertical loading.Moreover, the catastrophe theoryis introduced to solve the key issues of displacement development mode, energy diffusion boundary, energy equation establishment and catastrophic instability criterion in the system of rock-socketed piles in deep backfill. Thus, the bearing capacity of rock-socketed piles in deep backfill under vertical loading is obtained.Finally,combined with the hyperbolic tangent modulus method and the load transfer method, a new calculation method for nonlinear settlement ofrock-socketed piles in deep backfillis proposed to improve the design theory of rock-socketed piles in deep backfill.