Hi,
I’m applying a static pushover analysis on a 2D infilled frame, with three bays and three storeys. When I obtain the capacity curve of the infilled structure, initially I observe a high peak of base shear. After the value of base shear decreases sharply and then the curve is similar to a bare frame curve.
Is this behaviour related to the type of the structure? Or am I doing any mistakes?
Thanks
Nicoletta
capacity curve of a 2D infilled frame
Re: capacity curve of a 2D infilled frame
Hi Nicoletta,
The behaviour that you described seems to indicate a premature failure of the infill panels.
At the Initial stages, the presence of the infills causes an increase in strength and stiffness of your structure. However, depending on the properties assigned to the infill panels (e.g. ultimate strains) the infills may fail for a reduced displacement and, consequently, stop participating in the overall building response (sudden drop in capacity that you describe). After that stage, the structure continue to respond as a bare frame.
In any case I recommend you to evaluate some infill element parameters, such as strains, forces..., to make sure that the infill does fail, or if there is any other reason for that behaviour.
Cheers,
Romain
The behaviour that you described seems to indicate a premature failure of the infill panels.
At the Initial stages, the presence of the infills causes an increase in strength and stiffness of your structure. However, depending on the properties assigned to the infill panels (e.g. ultimate strains) the infills may fail for a reduced displacement and, consequently, stop participating in the overall building response (sudden drop in capacity that you describe). After that stage, the structure continue to respond as a bare frame.
In any case I recommend you to evaluate some infill element parameters, such as strains, forces..., to make sure that the infill does fail, or if there is any other reason for that behaviour.
Cheers,
Romain