Applicability of psinsar for building hazard identification. Study of the 29 January 2006 Katowice exhibition hall collapse and the 24 February 2006 Moscow basmanny market collapse

Due to heavy snow fall in winter 2005-2006, two building catastrophes happened in Katowice (Poland) and Moscow (Russia) killing and injuring dozens of people. Roof collapses, caused by heavy snow and ice accumulation were the direct causes, but it was questioned whether other circumstances such as construction stability would play an additional triggering role. Moreover, both buildings were located on unstable areas affected by underground coal mining (Katowice) and karst and suffusion phenomena (Moscow). We performed a stability assessment of the buildings, prior to the collapse, using Persistent Scatterer techniques on time series of SAR data. The main challenge of this study is the identification of a few representative coherent scatterers on individual buildings. The main conclusion of this analysis of ERS1/2 and ENVISAT data is that we found no significant indication of instability before the catastrophes.