On Jan 12, 3:27*pm, E Z Peaces wrote:
Today I saw the town maintenance man repair the elbow in a 2" plastic
water pipe, two feet deep in sandy soil.

He said water pressure had separated the joint. *His solution was a
steel stake on either side of the joint. *That's what he had before, and
it failed.

It seems to me that enough pressure to separate a joint could also, in
time, move a stake in wet, sandy soil. *Is that the best way to brace an
elbow undeground?

The guys in my area use bags of premixed concrete for 8"
underground irrigation pipe. Pressure won't exceed 80 psi probably.
Most often it stays under 50.
They just put the bags in around the elbow. The pipe is 5' deep or
maybe a little more. It might work to put a partial bag around the
pipe you described. Tamping it in around the elbow would help.