Last update: 29/4/2010 Rockfor.NET calculates the Probable Residual Rockfall Hazard (PRH) under a forested slope. PRH is the percentage of rocks that surpasses the forested area of a slope. To calculate the PRH of a given slope, the fields below should be filled in. As decimal-sign a full stop (.) has to be used. The underlying principles and methods are explained here. Please contact us for questions and suggestions.

Rock characteristics
Rock diameters (3x) (explanation)     m
Rock density (explanation)     kg m-3
Rock shape     -

Slope characteristics
Mean gradient of the slope (explanation)     degr. (º)
Height of the cliff (explanation)     m
Length of the forested slope (explanation)     m
Length of non-forested slope (explanation)     m

Forest characteristics
Mean stand density     ha-1
Stand basal area (Gtot)     m2 ha-1
OR
Mean stem diameter at breast height (DBH)     cm
Occurrence of dominant tree species:
- Norway spruce (Picea abies)     %
- Silver fir (Abies alba)     %
- European larch (Larix decidua)     %
- Austrian pine (Pinus nigra)     %
- Scots pine (Pinus sylvestris)     %
- Sycamore maple (Acer pseudoplatanus)     %
- European beech (Fagus sylvatica)     %
- Black locust (Robinia pseudoacacia)     %
- English Oak (Quercus robur)     %

Probable Residual Rockfall Hazard = 0 %

Target Stand:
Stand Density = 0 - stems per ha
Mean Stem Diameter = - cm

Input data for calculation
Mean Rock diameter = 0 m
Rock volume = 0 m3
Rock mass = 0 kg
Kinetic energy = 0 kJ
Mean stem diameter (DBH) = 0 cm
Maximum distance = 0 m

Rockfor.NET is a probabilistic tool that provides an estimate of the PRH. It should be used as expertise support. We assume no liability, whatsoever, for any actions taken based on the information provided by Rockfor.NET.

Rockfor.NET is developed by Frédéric Berger (Cemagref Grenoble) and Luuk Dorren. We gratefully thank the European Union for funding the Provialp Project (Interreg IIIa, Alcotra), as well as the Pôle Grenoblois d'Etudes et de Recherches pour la Prévention des Risques Naturels (PGRN) for the financial support. We also thank the community of Vaujany and the EDF (Electricité de France) for their support.