为探究类岩堆体地层结构的复杂地质特性与基本结构特征，分析隧道施工大变形及塌方机制并研究隧道围岩稳定性特征，以云南建（个）元高速公路他依隧道为例，采用现场调研与踏勘，变形量测以及围岩压力监测等方法，从类岩堆体基本结构特征、隧道建设工程问题与稳定性支护措施3方面进行深入研究与总结。结果表明： 类岩堆体围岩地层结构松散，成分复杂，极易受到开挖扰动作用影响，变形影响范围约为掌子面后方30 m；开挖后易出现大变形、塌方、初期支护结构破坏及突水突泥等灾害现象。开挖导致围岩变形与压力快速增大，最大变形接近350 mm，最大围岩压力350 kPa，钢拱架内力超过250 MPa，中下台阶开挖会明显降低上部结构受力，且隧道断面内变形与受力具有极度不均匀性。通过增加预留变形量，加大钢拱架型号，提升初期支护结构强度与刚度，增设双层护拱与加强拱脚支撑，注重超前加固与注浆等联合措施，可以保证类岩堆体隧道施工的安全与稳定。

To investigate the geological and structural characteristics of the taluslike rock mass, analyze the mechanisms of large deformation collapse during tunnel excavation, and explore the tunnel stability, a case study is conducted of Tayi tunnel of the JianshuiYuanyang highway. Detailed study is carried out on the basic structural characteristics of taluslike rock mass, engineering problems during tunnel construction, and support measures using site survey, field investigation, deformation measurement, and surrounding rock pressure monitoring. The results show the following: (1) The surrounding rock mass has a complex and loose structure, which is easily affected by the excavation perturbation. The influence range of deformation is about 30 m behind the tunnel face. (2) Some disasters such as large deformation, collapse of excavation face, failure of the primary lining, and water inrush are easy to occur after excavation. The surrounding rock deformation and stress increase rapidly due to tunnel excavation, the maximum deformation is about 350 mm, the maximum surrounding rock pressure is 350 kPa, and the internal force of steel arch frame exceeds 250 MPa. It is also found that the excavation of the middle and lower benches can obviously reduce the pressure and deformation around the upper bench. The deformation and pressure along the tunnel section are extremely uneven due to the uniform excavation profile. The safety and stability of tunnel construction in the taluslike rock mass can be guaranteed by enlarging the reserved deformation, improving the type of steel arch and the strength and stiffness of the primary support, installing doublelayer steel arch, strengthening the arch foot support, and implementing advance reinforcement and grouting.