Looking at photos of the damage to the four storey school dormitory building due to the earthquake in Turkey (NCE last week), the weakness of joints between the columns and beams appears to be the main cause of collapse.
The joints need to be designed and detailed for the reversal of forces due to the vertical acceleration of the earthquake.
As well as designing for moments and shear forces, the concrete at the joints should be contained by closed links around the joints both in columns and beams.
The questions are: how were these joints detailed and did the construction follow the detailing?
Dr Nutan Subedi, reader, University of Dundee, n. k. subedi@dundee. ac. uk