中文摘要：

关键块体在某种程度上控制着节理隧道施工的稳定性，同时存在着安全隐患。在设计和施工过程中，及时确定关键块体可减少工程事故的发生。文章结合辽宁境内高速公路钓鱼台隧道工程，采用块体理论和团队开发程序GeoSMA-3D系统，在现场调查的基础上对其进行不定位块体、定位块体和随机块体的搜索和初步确定，并分析了该隧道块体的稳定性。不定位块体分析中，给出三组结构面下，开挖面上可能形成的最大关键块体理论计算方法；定位块体分析中，根据确定性结构面信息，搜索开挖面上的关键块体；随机块体分析中，采用三维不接触系统对随机结构面进行测量统计，并搜索确定结构面与随机结构面共同作用下的有限块体和关键块体。三种不同块体的分析方法相互补充，从不同方面为工程设计及施工提供了依据。

英文摘要：

The stability and safety of a jointed rock tunnel is controlled by key blocks to some extent. It is important to avoid engineering accidents by making sure that key blocks are determined in a timely manner in the progress of design and construction. Based on the block theory and in-site monitoring, and using the design and construction of the Diaoyutai tunnel as an example, unlocated blocks, located blocks and random blocks are searched for and determined by the self-developed GeoSMA-3D system. The stability of the tunnel blocks is also studied. For studying the unloeated blocks, the theoretical calculation method for the possible maximum key block on the ex- cavation face is determined for three structural planes. For studying the located blocks, the key block on the excava- tion face is sought based on information regarding deterministic structural planes. For the study of random blocks, the random structural planes are obtained by a three-dimensional contact-free measuring system. The finite blocks and key blocks are sought for under the interaction of deterministic structural planes and random structural planes. The three different kinds of block analysis method are inter-complementary, providing the basis for engineering design and construction from different aspects.