Portable Steel Construction Barriers

[Bitmapped]

I've noticed in the last couple years that a lot of construction projects that require construction barriers have switched to using steel systems instead of the traditional segmented concrete barriers. Here's an example of a steel system along with a transition to a concrete system on I-79 outside Pittsburgh last fall: https://goo.gl/maps/gCo7rEWbcKxJrq7q8

It looks like Zoneguard is the name of at least one steel product. I'm curious if anyone from the engineer/DOT side knows anything about these systems and their sudden adoption. I'm assuming they're cheaper or easier to work with? It seems like these systems are normally anchored into the pavement, which I didn't normally notice with concrete barriers.

[jeffandnicole]

In that instance, those metal barriers are used around an s-curve. I imagine they wanted the lower barrier for sight distance issues since a driver can see possible upcoming congestion over the barrier easier versus PA's normal barrier which is higher.

I've also seen metal barriers used in areas where they need a few extra inches on narrow roadways. A few of DRPA bridges between NJ and Philly switched  to the metal zipper barrier because it yields another 6 inches. Not much overall, but if they can obtain another inch per lane when the lanes aren't the standard 12' wide, they'll take what they can get.