Arun,
Besides Richard Ay's explnanation, which is self explanatory, pl. note that SCALAR ADDITION ( as I have mentioned before , you should ponder why SCALAR and not ALBEGRAIC)is for code stress check for SUS+OCC only. Code does not recommend, how you need to add the restraint loads for different combinations.

The tensile / compressive I referred to was for "pipe stress only".When you are mentining "loads on restraints, so definitely it is compressive", are you referring to the compressive loading on the restraint ? What has pipe stress got to do with it ? Are you designing the piping or the supporting structure?

Pl. don't think I am trying to teach you or anything that way. I only feel that you need to study the code requirements and the intents in a better way.

Regards