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Process-based rockfall simulation models attempt to better emulate rockfall dynamics to different degrees. As no model is perfect, their development is often accompanied and validated by the valuable collection of rockfall databases covering a range of site geometries, rock masses, velocities, and related energies that the models are designed for. Additionally, such rockfall data can serve as a base for assessing the model’s sensitivity to different parameters, evaluating their predictability and helping calibrate the model’s parameters from back calculation and analyses. As the involved rock volumes/masses increase, the complexity of conducting field-test experiments to build up rockfall databases increases to a point where such experiments become impracticable. To the author’s knowledge, none have reconstructed rockfall data in 3D from real events involving block fragments of approximately 500 metric tons. A back analysis of the 2015 Mel de la Niva rockfall event is performed in this paper, contributing to a novel documentation in terms of kinetic energy values, bounce heights, velocities, and 3D lateral deviations of these rare events involving block fragments of approximately 200 m3. Rockfall simulations are then performed on a “per-impact” basis to illustrate how the reconstructed data from the site can be used to validate results from simulation models.

International audience; The impact of falling rocks on human activities can be hindered using protection measures such as rockfall barriers, embankments and other passive structures but also through the presence of forests. In order to study the effect of a forest on rockfall trajectory, a site neighboring a village in Central Greece was selected which has a well-recorded rockfall history in the last 50 years. The village is limited by a relatively dense forest, which lies on a limestone scree slope. An assessment of the role played by the forest stands on the site was done using the Energy Line Angle concept and conclusions on the residual rockfall risk on houses are drawn.

Cable yarding systems constitute an adapted solution for steep-slope harvesting in mountain forests. However, it requires many specific skills for both forest managers and operators. The objectives of this research were to: (1) develop a CableHelp model for the set-up of cable yarding systems where inputs are operational field data and outputs are load path and tensile forces, and (2) to validate it with field experiments. The results show a high accuracy between the data predicted by the model and field measurements. Furthermore, this work stresses the importance of taking into account both the mainline effect and the friction between skyline and intermediate supports to properly calculate the skyline tension and load path. The CableHelp model shows great adaptability and ensures highly accurate predictions for any position on the line profile and for different configurations: single-span or multiple-span profiles, uphill or downhill yarding and for different kinds of carriage. A direct application of this research is to optimize the set-up of cable lines in order to reduce equipment wear, as well as operating cost, while respecting operator safety.

Cable yarding systems constitute an adapted solution for steep-slope harvesting in mountain forests. However, it requires many specific skills for both forest managers and operators. The objectives of this research were to: (1) develop a CableHelp model for the set-up of cable yarding systems where inputs are operational field data and outputs are load path and tensile forces, and (2) to validate it with field experiments. The results show a high accuracy between the data predicted by the model and field measurements. Furthermore, this work stresses the importance of taking into account both the mainline effect and the friction between skyline and intermediate supports to properly calculate the skyline tension and load path. The CableHelp model shows great adaptability and ensures highly accurate predictions for any position on the line profile and for different configurations: single-span or multiple-span profiles, uphill or downhill yarding and for different kinds of carriage. A direct application of this research is to optimize the set-up of cable lines in order to reduce equipment wear, as well as operating cost, while respecting operator safety.

The paper presents a new approach to assess the effecctiveness of rockfall protection barriers, accounting for the wide variety of impact conditions observed on natural sites. This approach makes use of meta-models, considering a widely used rockfall barrier type and was developed from on FE simulation results. Six input parameters relevant to the block impact conditions have been considered. Two meta-models were developed concerning the barrier capability either of stopping the block or in reducing its kinetic energy. The outcome of the parameters range on the meta-model accuracy has been also investigated. The results of the study reveal that the meta-models are effective in reproducing with accuracy the response of the barrier to any impact conditions, providing a formidable tool to support the design of these structures. Furthermore, allowing to accommodate the effects of the impact conditions on the prediction of the block–barrier interaction, the approach can be successfully used in combination with rockfall trajectory simulation tools to improve rockfall quantitative hazard assessment and optimise rockfall mitigation strategies.