model construction sequence

[songlianglong]

My connection model simulated the assumed construction sequence for a moment resisting frame, where a posttensioning force is applied before a friction device is constructed.
So I want to activate the friction device element after the post-tensioning force was applied to the model. how can I make this construction sequence achieved in the opensees?
I used steel02 material to simulate the post-tensioning element,and if I do not consider the contruction sequence of the elements,the post-tensioning force would apply a initial force to the friction device element and this is not what I want.
Thank you !Very Happy