File talk:2010-02-21 48 11 zb Mammendorf 0116.jpg

These steel boxes are for safety of the workers that climb down into the ditch that is dug. These steel boxes are to prevent collapse of the dirt walls when someone is down in the ditch. They are standard equipment on any construction site in the US of A. --NWoodruff 12:50, 26 February 2010 (UTC)

Thanks! That makes a lot of sense! I guess they use them when laying foundations for bridges, then? Or could it have to do with building drainages to get some water out of the ground before putting down the RR tracks? I have seen other types of protective walls, but maybe these are used when the ground is kind of swampy? --Zb 19:38, 26 February 2010 (UTC)