CONSIDERATION ON STABILITY EVALUATION BASED ON LONG-TERM VIBRATION MONITORING OF BLOCK FIELDS

Abstract

 When block fields exist on the slope along a road, it is necessary to carry out rockfall surveys and take measures to prevent disasters. But rocks fall because of various, complex causative and triggering factors, and it is difficult to standardize the stability of a block field and evaluate it accordingly. The Rock-fall Vibration Survey method was developed for this reason. The survey is carried out by installing a vibration meter on the block field and using the dominant frequency and subtrahend constant of the recorded vibrations to quantitatively evaluate the stability of the block field. With this method, the vibration meter is installed and removed every time a measurement is taken, and measurements taken for only a short period of time are used to evaluate the stability. But it is possible that block field vibrations change, affected by the environment such as weather conditions. In this study, a facility to monitor the vibrations of unstable block fields is built, and points to keep in mind when evaluating the stability of block fields by analyzing the measured data are indicated.