Hello KRANTHI

if you only want to model stress distribution, use tie constraint.

be aware of you cannot model damage by tie constraint.

I don't understand why you think you need to use a rigid body Constraint? where?

Thank you Amirhossein Ghamarian for your answer. Yes i want to know the stress distribution in beam elements(i.e. which supports shell elements).

So according to you, i need to impose tie constraints at all positions where shell elements meets the beam elements. right?

Exactly, use tie constraints at the interface of shell and beam.

when you use tie constraint between two bodies, try to have overlapped nodes in the interface of two bodies ( here the bottom surface of the shell and top surface of the beam ), it increases the accuracy of the result. although this is an ideal situation and in many cases, we cannot create it completely.

Also, ABAQUS wants from you select master and slave surfaces.

in general law, the surface which belongs to the body with a higher modulus of elasticity is master surface and another is the slave surface.