Water disaster analysis and numerical simulation of a karst tunnel in a highway of Guangdong Province

The key factors to calculate the tunnel water inflow are studied based on the actual situation of a highway tunnel in the karst area. The tunnel water inflow rate is quantitatively analyzed with precipitation, rainfall intensity and infiltration intensity. According to the actual situation of Dabaoshan engineering site, precipitation infiltration method and underground runoff modulus method are applied to calculate the tunnel water inflow at the entrance on both sides in the wet season, and the maximum possible water inflow volume is analyzed under the heavy rainfall condition.The results show that the drainage capacity of the tunnel theoretically meets the requirement of drainage in the wet season, but will be affected by the heterogeneity of the material and the engineering, and the long-term effect of clogging.The impact factors of karst tunnel water in highway are identified in Guangdong area. Karst tunnel simulation models are established for both critical state and failure state of the water pressure.The results show that the critical value of water pressure increases with the thickness of the lining structure.