Abstract: Stability analysis is the core of geotechnical engineering，and block theory is one of the most useful analysis methods in this area.Although classical block theory has a critical base on mathematics，it is also the highly abstraction and assumption on the realistic world，and some distance exists with the actual demand.The basic principles of classical block theory and its recent extensions are summarized and compared.It is put forward that the analysis should be conducted by finiteness，mobility，active and positive stability.It is found that the discontinuities are the key to rock stability，and the joints simulations and block system construction are the core of the analysis.It is concluded that the stability of rock mass is not only controlled by internal factors like joints but also affected by external conditions like loads，and both of which vary with the time.And the possible development trends are pointed out，which can instruct the development of block theory.

Key words: stability analysis, block theory, discontinuous deformation analysis, numerical manifold method

摘要： 稳定性分析是岩体工程研究的核心问题，块体理论是常用的岩体工程稳定性分析方法之一。经典块体理论具有严格的数学证明基础，但它也是在对现实世界高度抽象和假定的前提下，与实际要求存在一定的距离。通过对经典块体理论的基本原理及其建立以来一些学者对它的研究和典型发展进行了总结和概括，提出了从有限性、可动性、主动稳定性和被动稳定性4个角度对块体进行整体分析，认为岩体结构面是控制块体稳定性的关键，结构面的模拟和块体系统模型的构建是块体稳定性分析的核心，发现块体稳定既受内在因素如结构面特征的控制，又受外界条件如各种荷载的影响，并且随时间而动态变化。最后指出了下一步可能的发展方向，对块体理论的发展具有积极的指导作用。

关键词: 稳定性分析, 块体理论, 非连续变形分析, 数值流形方法