A Jersey barrier, or Jersey wall, is a modular concrete or plastic barrier employed to separate lanes of traffic. It is designed to minimize vehicle damage in cases of incidental contact while still preventing the crossover case of a head-on collision. Jersey barriers are also used to reroute traffic and protect pedestrians and workers during highway construction, as well as temporary and semi-permanent protections against landborne attack such as suicide vehicle bombs. A Jersey barrier is also known in the western United States as K-rail, or K-wall, a term borrowed from the California Department of Transportation specification for temporary concrete traffic barriers, or colloquially as a Jersey bump. Plastic water-filled barriers of the same general shape are also now commonly called Jersey barriers.
https://en.m.wikipedia.org/wiki/Jersey_barrier
Created in New Jersey hence the name. Don’t know where you live but they may have a local name.
So in New Jersey, do they call them "joisey barriers" ??