Hi all;

I have to calculate a jacketed pipe as shown in the picture below
The spiders in node 10 and node 30 are modeled as restraints but in CAESAR II Application guide, in the example of jacketed pipe there is a spider modeled in each elbow.

I want to know for my case and in general I have to add a spider on each Elbow or the case of CAESAR II Application guide example is specific?