厄瓜多尔CCS水电站TBM法施工引水隧洞工程地质条件及问题初步研究

TBM法隧洞施工具有快速、高效、安全和环保的技术特点,但TBM施工地质适应性差,往往由于工程地质条件原因影响TBM的掘进效率,在TBM施工之前非常有必要对工程地质条件进行研究。以厄瓜多尔CCS水电站引水隧洞为例,分析岩石单轴抗压强度、岩石耐磨性和岩体的完整性等指标,得出该隧洞的地质条件适合TBM施工的结论。并根据工程区域的工程地质条件,分析施工可能遇到的工程地质问题,主要包括岩爆、断层破碎带塌方、软岩大变形、涌水、高地温及有害气体5个方面,并针对性地提出在各种不良地质条件下的预防措施和施工对策。

Case Study on Engineering Geological Conditions and Problems in Construction of Headrace Tunnel of CCS Hydropower Station in Ecuador by TBM Method

TBM tunneling method has many advantages,such as high speed,high efficiency,high safety and being environmental friendly.Due to the bad geological adaptability of TBM method,however,the TBM tunneling efficiency may be affected by the engineering geological conditions.Therefore,it is of great necessity to study the engineering geological conditions of the project before TBM tunneling is started.In this paper,the engineering geological conditions of the headrace tunnel of CCS hydropower station in Ecuador are analyzed in terms of uniaxial compressive strength,abrasiveness and intactness of the rocks and it is concluded that TBM method has good engineering geological adaptability in the project.Furthermore,engineering geological problems that may be encountered in TBM tunneling in the project,including rockburst,collapse in fault and fracture zones,serious deformation of soft rock,water inflow,high ground temperature and harmful gases,are analyzed and countermeasures are proposed.