Basic rockfall simulation with consideration of vegetation and application to protection measure

Abstract

Abstract. The estimation of risk due to rockfall is often done empirically. As a rational and effective method towards performance-based design of protection measures, a threedimensional simulation method helps to describe the motion of rockfall on a slope and to consider the effect of vegetation probabilistically. This document details a typical simulation method and analyses the manner of rockfalls paired with interference of vegetation and other factors. As application, an actual slope is analyzed where rockfall occurred during the Noto Peninsula Earthquake. Finally, the validity and the benefits of the shown method are the basis for a hazard mapping for rockfall and the planning of measures.

Quantifying the effect of forests on frequency and intensity of rockfalls

“…They reconstructed a decrease in rockfall rates after the recolonization of part of the slope where most of the forest was destroyed after a high-magnitude event in 1720. Masuya et al (2009), on the other hand, did not find a decrease in the number of blocks reaching the damage potential at a distance of 350 m from the rockfall source based on three-dimensional simulations taking vegetation probabilistically into account, but an increase in the spread of the rockfalls and lower rock energies. It has to be mentioned that the considered vegetation cover featured relatively small trees and low tree density.…”

“…In the case of protection forests, quantitative, risk-based approaches have been only rarely applied in the past. Despite the advanced knowledge on the protective effect of forests and its maintenance (Dorren et al, 2007;Bigot et al, 2009;Radtke et al, 2014;Fuhr et al, 2015), open questions remain on how protection forests can be quantitatively integrated into rockfall risk analyses (Masuya et al, 2009;Trappmann et al, 2014). Currently, the effect of forests is mostly neglected or only qualitatively assessed in hazard and risk analyses.…”

Design and Evaluation of a Low-Power Sensor Device for Induced Rockfall Experiments

“…This leads to a delicate trade-off between the immediate financial burden of the protection measures and the safety risks involved. Simulation and estimation software solutions based on mechanical models have been investigated and developed recently [6][7][8][9][10][11][12][13][14]. Today, state-of-the-art solutions are able to perform accurate rockfall trajectories simulations, and they are crucial tools for civil engineers to improve the risks assessments and develop mitigation strategies [6], [7], [15].…”

Summary on the NHESS Special Issue "Rockfall protection – from hazard identification to mitigation measures"

“…The rockfall propagation in the transition zone is then best evaluated by trajectory simulations as described by Masuya et al (2009). A challenge is the knowledge and the modelling of the boulder ground interaction during the moving process.…”