ABSTRACT

Most studies investigate the mechanism of tunnel seismic damages due to earthquakes by numerical simulation and physical model experiments. However, limited by inevitable simplifications, assumptions and boundary problems, the above methods deviate more or less from the real situation. Therefore, this research acquire the seismic response of a rock tunnel through in-situ monitoring. Five accelerometers were installed in a highway tunnel in southeast Taiwan, four on the same tunnel section, one on another. Since the monitoring started from 2014, there are four earthquake events exceed Richter magnitude 4.0. The acceleration records show that in general, the predominant frequencies of accelerometers installed in different locations inside the tunnel are similar with the predominant frequencies of the two neighboring seismic stations. Such similarity in predominant frequencies possesses the best consistency along the slope dip direction, and the worst along the vertical direction.