Abstract: The Daqiulin 2nd Tunnel is a separated bidirectional fourlane highway tunnel. Due to the unfavorable geological as well as topographical conditions, the potential construction interruptions resulted from the instabilities of the rock mass, could have lengthened the construction schedule and increased the investment. During the construction of this tunnel, the instability of the rock mass was forecasted with the both the Tunnel Seismic Prediction (TSP) form the long distance and the Ground Penetrating Radar (GPR) in the short distance. The deformation of the tunnel roof and the surrounding rock mass; the stresses in the supporting system and in the rock mass were also monitored. The construction safety is able to be warranted.

Key words: Tunnel in Mountains, Geological Hazard Forecasting, Construction Monitoring, Instability of Surrounding Rock Mass