Bonding Composite laminated Shell model

[Englapoo]

Hi,
I have to dimension the overlap surface between two carbon/epoxy composite parts. The joining geometry is single lap joint type. My entire model is formed by shell99 element. How can I simulate the bonding to catch the stress in adhesive and at interface and verify if it's in failure.
I wan't use Shell solid assembly, becouse the number of elements will increase extremely due to the small size required in the joint.
Any Idea?

thank you