Abstract:

Xiangshan tunnel on LongyanXiamen railway is assessed as a high risk tunnel due to the complicated geological conditions. The geological conditions of No. 1 and No. 2 inclined shafts in karst areas are extremely adverse. Because of the rich ground water, high construction risk and tight construction schedule, several geology prediction methods are used in Xiangshan tunnel for the purpose of comprehensive geological condition forecast, among which prediction by georadar is precise in probing the karst near the working face. The characteristics and advantages of geology prediction by georadar are presented in this paper. Furthermore, the application of geology prediction by georadar in the karst area of the left tube in No. 1 inclined shaft lot is analyzed and summarized and the prediction results are compared to the actual conditions revealed after excavation.

Key words: high risk tunnel, karst area, georadar