Cyclic thermal load

I need to apply cyclic thermal load on a layered structure and want to see the stress generated and structural displacement using Ansys. How can I apply cyclic thermal load? iI tried to use Load Step Opts. Since I am interested only in stress-displacemnt, I used structural element. But if i use structural element, it doesn't give me Time/frequency option under load Step. Do i need to use coupled element? Is there any other way to apply cyclic thermal load to see stress-displacement? Thanks!