针对复杂地质条件下高边墙、多洞交叉的大型洞室群多步开挖过程中的强卸荷特点,采用经验类比、数值分析、智能分析等方法的综合集成,提出复杂条件下大型洞室群稳定性分析、开挖过程与支护设计的智能动态设计方法。该方法以解决大型地下洞室群不同设计阶段稳定性需要解决的关键问题为目标,从地质条件的认识、地应力分布特征的把握、高边墙多洞室交叉的围岩变形破坏机制的理解到围岩稳定性评价、破坏模式识别、调控措施(开挖过程和支护方案)全局优化以及施工过程中的反馈分析与动态调整的系统全过程进行研究,论述地下洞室群修建前的初步设计方法和洞群修建过程中的动态最终设计方法。在锦屏二级水电站地下厂房设计与施工全过程的应用实践表明,该方法可以实现大型洞室群设计与施工的信息化、智能化和科学化。
Focusing on characteristics of strong excavation unloading of high sidewalls of multi-cavern group under complicated geological conditions,an intelligent and dynamic design method is proposed for the stability analysis,design and construction of large cavern group.The method aims at the safe and economic construction for the large cavern group under complicated geological conditions.It considers the entire system's process from recognition of geological conditions,back analysis of in-situ stress field,understanding of deformation and failure mechanism of surrounding rock of large cavern group,stability analysis,global optimization of control measures of the stability such as excavation procedure and support parameters of cavern group,and dynamic adjustment of the excavation procedure and support parameters during the construction.The method has been in good practice of design and construction of underground powerhouse at Jinping II hydropower station.The results show that it is reliable information,intelligent and scientific method for design and construction of large cavern group.