Analysis of Large-Span RC Shells Collapse in the Last Decade

Large-span reinforced concrete shells collapses in the last decade caused many death-roll as well as significant losses to national economies. The most famous cases were the collapse of Aqua-Park cover in Moscow in February 2004 and the 2E terminal roof destruction at Charles De-Gaul Airport near Paris in May 2004. Following the publications of the appropriate commissions that have studied the reasons of these events, the influence of concrete creep and changes in the shell geometry on buckling of RC thin walled shells was not properly considered in the design. This study is focused on buckling of such shells, taking into account geometrical and physical non-linear behaviour of compressed concrete. Other important reasons of concrete shells collapse are also analyzed. The study is partially based on available experimental and theoretical investigations of RC shells, previously performed by the first author. The results of those investigations, obtained for small scale models of thin walled shallow RC shells, are discussed. Behaviour of the tested models is compared with that of the above mentioned real shells and similar structures, which also collapsed. The critical loads for the shells are obtained. It is shown that these loads are lower then the actual ones, thus the shells buckling was unavoidable.