Column rebars must be properly anchored to the upper floor level in order to behave in the correct way. The most effective way to anchor the upper floor column rebars is by creating a “concrete cap” on the top of the column thus allowing the rebars to be anchored without being bent.
If the construction of a ‘column cap’ is not a desirable solution due to reasons like e.g. the need for a flat roof, then the column rebars of the upper floor can be anchored according to one of the existing ways.
The reduction of the column’s size from one storey to the other is not favorable either from a theoretical or from a practical point of view. Especially in columns where earthquake resistant behavior is required it must be avoided.
