I've used mesh fiberglass tape (the type you buy for wall repairs), combined with JB ClearWeld. It worked really well repairing my STTNG Subway which, of course, is hidden from view. It's nice that your ramps aren't clear, so that will help hide the repair work some. You should sand the surface of the plastic, to achieve a better bond with the clearweld.

There was a big chunk of the plastic missing, and I've attached a photo showing the after effect. It's not the prettiest, but I wasn't going for pretty. I was going for strong.

IMG_4860.JPG

in a "grab now" pinch, fiberglass seam tape is good stuff, its a more open mesh and thicker strands, where fiberglass cloth is thinner with a higher thread count weave (*like bed sheets). my preference for model boats (full size too) is epoxy resin and fiberglass cloth.

*lol speaking of.. yes you CAN use a light weight cotton cloth and crazyglue very similarly, and I'd go with it for being common household available inexpensive, my preference for fiberglass cloth aside, old bed sheet cloth and crazyglue will lock up fast and plenty solid. apply wetted layer, let dry, sand, another wetted layer.. repeat until you think its thick and strong enough.
if it seems funny or funky, try it as an experiment on something else first, you'll sure see it.

stronger? cut the cloth shapes at 45 degree angles (or 30 and 60) to the weave of the cloth and alternate them in as layers to get more omnidirectional strength.