Kenneth,

After reading your request, I see that you the bamboo is now running amuck where it has never been before. It sounds like you have running bamboo which is of the non-clumping variety. I see that you have been controlling with barriers but now it is outside of the barriers. It sounds as if the barriers have either broken down or the bamboo has now grown under the barriers. The problem with bamboo of the running type can grow down under most barriers if not dug down deep enough. If they are only dug to a depth of 12 inches over time the bamboo can grow downward to a depth of over 20 inches. If you want to control the bamboo again then you must dig 3 feet from the bamboo down to a depth of at least 28 inches or until when digging around the bamboo the rhizomes can no longer been found in the soil around the plants. and then I would dig another 12 inches in depth. I would now install a metal barrier with a thickness of 1/8 inch in thickness or a plastic heavy weight thickness to prevent the plant from breaking down the barrier on time. Remove all rhizomes from the plants out to 2 feet from the plants remove all the soil and cut out all the rhizomes back to the plant base, once you install the new barriers around the plants the backfill the soil you had previously removed to the barrier area. This will take time, but it is worth it 

resources:

Bamboo Growth and Control - Alabama Cooperative Extension System (aces.edu)

Containing and Removing Bamboo | University of Maryland Extension (umd.edu)

Controlling Bamboo in Landscape Plantings | NC State Extension Publications (ncsu.edu)

bamboocontrol.pdf (uconn.edu)