Barbed Wire was a craft-able building material. It doesn't have much HP, but it does work to slow down the Zombies while damaging them a little. It can be found at various generated points of interest as a barrier to ward entry.
To craft a Barbed Wire, Either click on the ingredients in your inventory and select “Recipes” then Barbed Wire and “Craft”, or search for Barbed Wire in your crafting window search bar.
In a few tests, zombies tended to avoid the barbed wire by walking between rows, or around it entirely. This could potentially be used to redirect a wandering zombie or possible horde from your general area if placed correctly. (Zombies walking parallel with the wire and perpendicular to the wire avoided it) Parallel seems to work better than perpendicular, but both seemed to deter zombies from general area. *(outdated information)*