Study on the principle of tunnel collapse treatment and its application

Collapse of crowm broked out with large water gushing at working face during driving tunnel in Ming Ya Zi tunnel's right tube. According to engineering geology condition and analysis of causes of collapse, double-deck prior ductile grouting reinforcement technique was applied in tunneling surrounding rock consolidation based on the strong pre-support theory.And the result of treatment was successful.Thus,guiding the work of tunnel collapse treatment by strong pre-support theory was proved reasonably and effectively