Video: Yeah, I'm not ashamed to admit this: I feel slightly less comfortable when I'm under a tunnel than when I'm not. It's not that I think that the tunnel will collapse on me - it's because I know the sky absolutely won't. This tunnel would put my fear into overdrive because it looks like it would totally collapse. It has no permanent support work and the entire construction process looks like piecing together Lego bricks. Yet it can support so much weight and still stand up. Sorcery is at play, obviously. But it's also the work of the Zipper truck system. Lock Block Ltd writes:
This video shows the versatility of the Zipper truck system. We are able to create tunnels with openings very quickly with no permanent support work. This arch can be used as a mining reclaim tunnel or storage vault with top access.
They really just put the blocks together and then hope it all sticks after the truck pulls out of the tunnel... and it totally does.