Cable Ampacity - Triplexed Cables

For library “ Directly Buried Cable – Detail 8 or Detail 7 “ . These should be triplexed cables, I’m not sure why they show up as not being in a triplex form but rather just side by side?

Per R&D,
We use equilateral configuration and it is a little more conservative and is on the safety side.
Creation date: 1/23/2017 2:52 PM      Updated: 1/23/2017 2:52 PM