| We carried out a field test to develop a method of simply and precisely identifying unstable rock blocks by measuring vibrations of a rock cliff. This method of identifying unstable rock blocks is based on the idea that in contrast to stable rock in which surrounding cracks adhere closely and are integrated with the foundation, in unstable rock blocks, the cracks have opened and deteriorated, causing separation from the foundation, with the result that unstable rock vibrates more than stable rock. |
