Influence on failure modes due to landslide extension

The physical dimensions of the buildings - with respect to the front - influence the possible damage modes and types of collapse. In this sense, it can be useful to refer at the following dimensions:

d_L Landslip size;

d_A maximum artifact dimension.

Depending on their ratio, it is possible to identify three states:

d_L << d_A Damage related to a limited part of the infrastructure (Cracks or partial collapses);

d_L < d_A Damage related to a part of the infrastructure (cracks or collapses);

d_L ≥ d_A Wide damages to the whole structure (loss of rigid equilibrium or collapse of larger parts).

The d_L/d_A ratio is therefore a first element to consider to evaluate the vulnerability of an historic building and can be considered as a synthetic indicator for a rapid assessment of the landslide risk.