基于集对分析模型的岩溶区浅埋穿河隧道突涌水危险性评价 postprint

Abstract: Tunnel construction in karst area often faces geological disasters such as water inrush , especiallyfor the construction of shallow tunnel under river , which is a very challenging work. Due to the in situ faultfracture zone , high weathering degree of rock mass , and the development of joints and fissures in the tunnelsite , the possibility of river water intrusion into the tunnel is greatly increased. In order to effectively evaluate the risk of water inrush in karst shallow tunnel under river, according to the geological conditions andtunnel characteristics of the tunnel site,11 factors affecting the water inrush , such as formation lithology,modified strata inclination, soluble and insoluble rock contact zones , surrounding rock grade , fault zonewidth ,fault property , fissure development degree , surface water flow , surface catchment area, buried depthof tunnel , construction disturbance degree , are selected as the evaluation indexes , and the risk evaluationsystem of karst shallow tunnel under river is established.The analytic hierarchy process (AHP) was usedto construct judgment matrix to determine the weight of evaluation indexes , the set pair analysis methodwas used to calculate the connection degree of each evaluation index , and then the comprehensive connec-tion degree of evaluation samples was determined.Secondly , the maximum membership degree principlewas used to identify the risk level of water inrush.Finally , according to the corresponding relationship be-tween the risk level and the water inflow, the scope of water inrush inflow can be preliminarily predicted.ln view of the risk of water innush in shallow buried section of Yuelongmen Tunnel under-crossing Gao-chuan River , the set pair analysis model was used to analyze the risk. 'The calculation results show that therange of water inrush volume predicted by the risk assessment is 3 000 ~ 10000 m'/d,and the actual waterinflow from site excavation is 7 000 m'/ d. That is to say , the results of risk assessment are basically con-sistent with the actual situation , which verifies the rationality and feasibility of the evaluation system andmethod and provides effective support for risk assessment of water inrush of karst shallow tunnel underriver.