## 3 Methodology for Evaluating the Effectiveness of Rock Fall Protections
### Analysis of the Effectiveness of the Protection Measures  
The evaluation of the effectiveness of rock fall protections is conducted based on a heuristic approach, which translates the qualitative information collected from the inspection on site into quantitative terms, by means of coefficients expressing a quantitative \"loss\" in the performance of the protection, called penalty coefficients. The possible values for the penalty coefficients vary in the interval (0,1), where: \begin{table}
\begin{tabular}{c c c c} \hline \hline  & \multicolumn{3}{c}{**(6) Retaining Walls**} \\ \hline
**n.** & **Factors** & **Type** & **Category** \\ \hline \multicolumn{3}{c}{**General (concrete, masonry, gabion, anchored and wooden walls)**} \\ \hline
1 & Loss of effective height due to blocks cumulated behind Maintenance & 1 \\ \hline \multicolumn{3}{c}{**Concrete wall—Sub-type specific**} \\ \hline
2 & Corrosion of reinforcement rebars Maintenance, design, life span & \(1,2,4\) \\ \hline \multicolumn{3}{c}{**Gabion wall—Sub-type specific**} \\ \hline
3 & Corrosion & Maintenance, design, life span & \(1,2,4\) \\ \hline \multicolumn{3}{c}{**Anchored wall—Sub-type specific**} \\ \hline
4 & Corrosion & Maintenance, design, life span & \(1,2,4\) \\ \multicolumn{3}{c}{5} & Rupture of the anchor Maintenance, design, installation, life span & \(1,2,3,4\) \\ \multicolumn{3}{c}{6} & Rupture of the head plate Design, installation & \(2,3\) \\ \multicolumn{3}{c}{7} & Faults of injection (sealing) Installation & \(3\) \\ \multicolumn{3}{c}{8} & Flaws in controlling applied stress Maintenance, design, installation & \(1,2,3\) \\ \hline \multicolumn{3}{c}{**Woodon wall—Sub-type specific**} \\ \hline
9 & Corrosion of metal elements Maintenance, design, life span & \(1,2,4\) \\ \multicolumn{3}{c}{10} & Fire Maintenance, design & \(1,4\) \\ \multicolumn{3}{c}{11} & Penetration by blocks Maintenance, life span & \(1,4\) \\ \multicolumn{3}{c}{12} & Rupture of components Maintenance, life span & \(1,4\) \\ \hline \multicolumn{3}{c}{**(7) Ditches and berms**} \\ \hline
**n.** & **Factors** & **Type** & **Category** \\ \hline \multicolumn{3}{c}{**Ditches**} \\ \hline
1 & “Springboard” effect due to filling Instability of any of the faces of the ditch Maintenance, design, installation & \(1,2,3\) \\ \multicolumn{3}{c}{1} & Loss of effective depth due to blocks cumulated inside Maintenance & \(1\) \\ \hline \multicolumn{3}{c}{**Berms**} \\ \hline
4 & Loss of effective height due to blocks cumulated behind Maintenance & \(1\) \\ \multicolumn{3}{c}{5} & Possibility of blocks rolling over the downslope face & Life span & \(4\) \\ \multicolumn{3}{c}{6} & Instability of any of the faces of the berm Maintenance, design, installation & \(1,2,3\) \\ \hline \hline \end{tabular}
\end{table} 
Table 2: _Cont._* 0 means the corresponding factor has such a high influence on the behaviour of the protection that it makes it totally unserviceable (associated to highest severity);
* 1 corresponds to null or negligible influence of the factor on the performance of the protection measure (associated to lowest severity), i.e., the protection can work as per design.