隧道突水突泥致灾构造分类、地质判识、孕灾模式与典型案例分析

Classification,geological identification,hazard mode and typical case studies of hazard-causing structures for water and mud inrush in tunnels

致灾构造是突水突泥灾害发生的内在条件和控制因素,突水突泥致灾构造兼具蓄积地下水的自然属性与突水突泥致灾性的社会属性,是地质条件与地下工程活动相互作用的综合体。通过221例突水突泥灾害案例统计分析,将突水突泥致灾构造划分为3类11型,即岩溶类(溶蚀裂隙型、溶洞溶腔型、管道及地下暗河型),断层类(富水断层型、导水断层型、阻水断层型),其他成因类(侵入接触型、层间裂隙型、不整合接触型、差异风化型、特殊条件型),研究不同类型致灾构造的结构特征、赋存规律和地质判识方法,并开展典型案例分析。统计分析表明,岩溶类致灾构造突水突泥数量居首(约占48%,105例),断层类次之(约占29%,65例),最后为其他成因类(约占23%,51例)。提出4种典型的隧道突水突泥孕灾模式,即直接揭露型、渐进破坏型、渗透失稳型和间歇破坏型。研究成果为突水突泥灾害的致灾机制与灾害控制研究奠定了基础,对隧道安全施工具有借鉴和指导意义。

Geological structure form is the intrinsic condition and the controlling factor of water and mud inrush. The hazard-causing structure of water and mud inrush was classified into 3 categories including 11 types. The first category is karst,including 3 types,i.e.,the corrosion fissure type,the karst cave type and the piping and underground river type. The second category is fault,including the water-enriched fault,the water-conductive fault and the water-resistive fault. The third category is due to the other causes,such as the intrusive-contact type,the interlayer-fracture type,the unconformable-contact type,the differential-weathering type and the special-condition type. 221 cases of typical water and mud inrush disasters were analyzed. The karst category is about 48%,including 105 cases. The fault category is about 29%,including 65 cases. Others are about 23%,including 51 cases. The structural characteristics,occurrence regularity and geological identification methods for different types of water and mud inrush hazard-causing structures are proposed and discussed. In addition,typical case studies are carried out. Finally,four typical hazard modes of water and mud inrush in tunnels are proposed,i.e.,the directly revealed type of water/mud inrush,the progressive failure type of water/mud inrush,the seepage instability type of water/mud inrush and the intermittent failure of water/mud inrush.