Is there anything to help reinforce PVC pipe?
Either you glued them correctly (I prefer &quot;cleaner, then primer, then glue&quot; for the most reliable connections) or you'll need to re-glue them after the joints fail.
Nothing you add to the outside will change that.
You do need to paint or otherwise cover them to prevent damage from the UV in sunlight, since you mention that they are above-ground.
Duct tape is a poor choice, it falls apart outside rather quickly.