Abstract
Estimating the rockfall risk degree of boulders on slope has been intensively challenged by the agencies and business owners, such as railway companies. In the current practice, some experiential methods based on the statistical analysis of the past rockfall incidents are widely used, since the outbreak mechanism of rockfall is still not fully understood. In this study, an estimation method of the risk assessment for the boulder-type rockfall is proposed in order to meet the railway companies' needs for evaluating the rockfall risk in an objective/quantitative manner. The proposed method will enable us to reveal the in-soil penetration depth of the boulder on slope by vibration measurement and calculate the dynamic stability directly. By applying the proposed method to the field slope along the railway, the validity of this method has been confirmed.
