portal frames sap2000 1

[homestate_s]

I am making a review of some portal frame designs i did and trying to find ways to optimize them on sap2000 the best way i can.
I discovered from some literature that rafter-column connections with haunches at the eaves and apex of the frame can be assumed to be "moment resisting" connections therefore would it be reasonable to apply body constraints which constrain (DOFs) both translation and rotation in all directions at the eaves and apex joints? i released by doing this ,my design becomes optimized and hence i am able to use smaller members for my columns.
attached to this is a snapshot of the body constraints I'm thinking of applying to optimize my design.

 

[wrxsti]

aroooo?

 

[homestate_s]

??

 

[HTURKAK]

You may assume "moment resisting" or fully rigid connection but body constraint is totally different concept. Not sure that you understand or applied correctly the body constraint concept.

By definition ( copy and paste from CSI web)

(Body constraint is applied to a set of joints that translate and rotate together as a rigid body. Rigid behavior is automatically applied to all DOF within the constraint, though only certain DOF may be specified. Body constraints (1) simulate rigid connections; (2) connect portions of a model that are defined by separate meshes; and (3) connect frames to shells.)..

Pls look also Diaphragm constraint..


In your case , for the haunched beam conn. the 6 DOF constrained literally means the moment effects are considered at the offset distance from the column .

https://wiki.csiamerica.com/display/tp/Body+vs.+equal+constraint

I will suggest you to study tutorials and better get experience , working together with a senior engineer.

 

[homestate_s]

@HTURKAK
Makes sense, THAKNS FOR THE RESPONSE
.I had initially assumed that sap2000 automatically took into account the behavior of a "rafter-column" connection hence nothing needed to be done at the apex and and eave connections when modelling.
I then discovered body constraints when simulating composite behavior between a steel beam and a concrete (first floor)slab which were connected with shear studs .only then did I apply body constraints at the connection points.