Last year, I threw up a quick trellis using a metal fence post in the ground and a 15 ft. bamboo pole attached to it using stainless hose clamps. I tied the twine to each mound with a smaller (3/8") steel post that was pounded in to the ground next to the mound and bent over the mound. This worked great until a 45mph gust snapped the 3" thick bamboo completely in have at the top of the fence post. That was later in the season, so I just lowered it down and re-clamped the now-shorter pole.
it got a little top heavy, with 4 bines per mound (12 total).
This year, I am going to move these crowns to the backside (south-facing) of my steel building (~20ft.) and run the twine between the raised beds and up underneath the metal roof where I can access them from the inside. Should be a much better operation.