Development of a damage simulator for the probabilistic assessment of building vulnerability in subsidence areas

• A damage simulator is developed to assess hazard and damage in subsidence regions.
• Hazard assessment uses influence function methods and different scenarios.
• Damage assessment use vulnerability functions.
• A probabilistic approach is developed to study uncertainties.
• Results show influence of uncertainties over the risk mapping.

The extraction of ore and minerals by underground mining often causes ground subsidence phenomena and may result in severe damage to buildings. Risk analysis in subsidence regions requires the assessment of both the hazards to and vulnerability of nearby buildings. However, many uncertainties exist and this assessment and its representation as well are still a complex objective. For this purpose a damage simulation tool is developed to investigate hazard and vulnerability under several possible scenarios of mining subsidence in which a large number of buildings may be affected. Ground movements assessment is based on the influence function method, and building damage is estimated using vulnerability functions. A case study is presented to illustrate the different results given by the damage simulator. Uncertainties about the collapsed zone of the mine and influence angles lead to the definition of different possible scenarios. A relative occurrence probability is then defined to implement a probabilistic approach to the hazard and vulnerability assessments. Different results, more or less synthetics, can then be obtained to assess both hazard and vulnerability over the exposed city. These results are compared and the maximal horizontal ground strains and the mean damage appear to be the most effective and relevant way to address the question. A final ranking based on scoring is then provided.