performance criteria check

[zthaer]

dear all;
i need a quick explanation in which how an element did not reach the near collapse chord rotation capacity but it did reach the crushing strain for much lesser load value.my three points are 1) the element should reached such capacity if i check other performance level (for instance the life safety).
2) the second is that the element reached the crushing because its little ductility or the global response is translation in which little ductile rotations involved
3) since i keep the strength even when such crushing is occurred, the over all capacity is maintained.

any help please, i need it.
best;
Thaer

[seismosoft]

Hi zthaer,
What is the crushing strain that you have introduced in the performance criterion?

[zthaer]

a concrete strain of -0.006,

[seismosoft]

How did you calculate it? Is it in accordance with the sectin details, e.g. transverse reinforcement?

[zthaer]

no i did not calculate any, i just use the default value of crushing strain of concrete to check all columns
do i need to calculate any thing ??

[zthaer]

dear Seismostruct team;
i still need a clarification;
any help;
best;

[z.gronti]

Dear Thaer,

The chord rotation capacity of the section and the concrete strain are two different criteria. With the first one you check the chord rotation capacity of the whole section, taking into account the reinforcement, whereas with the second one you just check the strain of the concrete.

[seismosoft]

Thaer,

The default value of 0.006 is obviously indicative. The correct value can vary significantly from section to section, depending on many parameters such as the section reinforcement, dimensions, the strength of materials etc.

It should be noted that the current post is related to a general earthquake engineering issue, which you should discuss better with your supervisor. Alternatively, you can refer to any good textbook. The current forum is a a forum for Seismosoft's program, rather than a general forum for the discussion of different issues regarding earthquake engineering in general.

Seismosoft Support