Investigation of monolithic frame with initial punching damage under accidental impacts

Abstract

According to regulations and standards, all buildings and structures must fulfil the requirements for mechanical safety. At the same time, the safety of structures must be ensured throughout their entire service life. The annual increase in the number of accidents due to terrorist acts, domestic gas explosions, collisions of vehicles with load-bearing structures, etc. has led to the creation of normative documents on the protection of buildings from progressive collapse. At the same time, the issue of buildings sustainability, which were designed without taking into account these requirements and which may have suffered localized damage during operation, remains open. Such buildings include monolithic houses with flat slabs, which have been erected since the beginning of the XXI century. The aim of the work is to study the resistance of these frames to accidental impacts and the influence on the survivability of structures of local defects in the most critical zone of the column-slab junction. Calculations on stability assessment in case of emergency of a fragment of a 9-storey monolithic building have been performed and it has been established that at certain combinations of damages in the support zones, progressive destruction of neighboring structures may occur.