CONSTRUCTION TECHNOLOGY OF TBM EXCAVATING THROUGH SECTION OF UNFAVORABLE GEOLOGICAL CONDITION
TBM通过不良地质地段的施工技术

Unfavorable geological conditions of highly developed fault fissures and aboundant underground water exist in the TBM excavation of Kunming Shanggongshan water divertion project in west China. The rock mass encountered in most length of the tunnel belongs to Class IV and V according to the applicable national standard. By taking effective measures,such as preceding geological drilling,polyurethane foam injection,increasing water tanks,employing drain pipes of bigger diameter,the problem of water gushing is solved,which,in turn,decreases the risk of collapses at the working face and ensures the safety and progress of TBM operation.