狮子山隧洞突涌介质特性与致灾模式

为了掌握玄武岩地层向斜构造不良地质体构造特征与突泥突水机制，以滇中引水工程狮子山隧洞穿越乌龙坝向斜构核部附近突水突泥灾害为例，研究了该段突水突泥灾害演化与致灾地质构造、致灾介质基本特征与致灾动力及诱发机制。结果表明：(1)突涌原因为构造向斜上盘节理裂隙密集带储水构造使下位凝灰岩裂缝扩展发育崩解软化、泥化，连接上部储水构造体，导致致灾介质体突涌；(2)突水突泥致灾介质类似稀性泥石流，瞬时爆发涌出，携带巨大能量；(3)隧洞卸荷坍塌、地下水作用及应力释放等共同作用导致了灾害形成。研究成果对隧道穿越褶皱构造防治突泥突水灾害具有一定指导意义。

Characteristics and Disaster Model of Inrush Medium in Shizishan Tunnel

The aim of this study is to understand the structural characteristics of unfavorable geological bodies and the mechanism of mud and water inrush in the syncline structure of basalt strata. We investigated into the evolution of water and mud inrush, the disaster-causing geological structure, the basic characteristics of disaster-causing medium, the disaster-causing power and the disaster-inducing mechanism at the core of Wulongba syncline structure in Shizishan tunnel of Central Yunnan Water Diversion Project as a case study. Results demonstrated that the water inrush is resulted from the disintegration, softening and argillization of lower tuff cracks caused by the water storage structure in joint fissure dense zone of the upper syncline structure; 2) the diluted debris flow like water inrush medium carries huge energy while bursting instantaneously; 3) the water and mud inrush disaster is caused jointly by tunnel unloading collapse, groundwater action and stress release. The research finding is of guiding significance for mud and water inrush prevention for tunnels crossing fold structure.