Pipe Bulkwall Design

I am designing a bulkwall for a 42’’ hdpe pipe. The pipe is to be abandoned in place via grout fill, hence the need for a bulkwall. Anyone know of any sizing equations and/or standards that I should be aware of? I have been looking at bulkwall design standards from the US Bureau of Mines Information, but this is likely not the best reference for information in my case.
My concern is the masonry is not adhering to the HDPE surface. The fill is required to meet 300psi (Union Pacific requirement) so it will likely be a clsm mix with a water reducer. The longest flow section is about 500’.


Just build a wall of concrete blocks and fill SLOWLY. Monitor the bulkhead as the pipe fills.
Attach a curved steel angle all around the HDPE. Shotcrete the angle to the block. Maybe add a few #4 rebar before the shotcrete.
Shotcrete is a sprayed on concrete - cement sand and pea rock. Call a couple contractors that do that work.

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