07-31-2010, 02:19 PM
OK I'll stick my neck out........the "grass" on top of the concrete, is probably left as the water recedes. Deeper water, up near the underside of the bridge, probably moves too fast, and scours the bents of any debris. As the water level decreases, the flow rate is slower, and dead grasses can end up being left where you see them, instead of being washed away.
It also looks like the bridge sections extend from one bent to the next. On top of those are the retainers for the ballast, four per side per bridge section, which is why there are three equidistant "stained" areas, on the bridge sections, from water/dirt washing down through the joints.
That same dirt, has easier exit from the bridge deck, at the section boundaries, down on top of the bent caps, and doesn't get to the sides there.
Yeah, when i was a kid, I drove my parents to distraction with that ever repeated question...........w h y y y y ?
I'm still never satisfied until I can figure out, "why it looks that way". When I do, I can understand not only "the question", but exactly how the thing is put together. Not a bad piece of information, if one is going to build a model of it.
( or....a pretty good story for why it was modeled that way )
It also looks like the bridge sections extend from one bent to the next. On top of those are the retainers for the ballast, four per side per bridge section, which is why there are three equidistant "stained" areas, on the bridge sections, from water/dirt washing down through the joints.
That same dirt, has easier exit from the bridge deck, at the section boundaries, down on top of the bent caps, and doesn't get to the sides there.
Yeah, when i was a kid, I drove my parents to distraction with that ever repeated question...........w h y y y y ?
I'm still never satisfied until I can figure out, "why it looks that way". When I do, I can understand not only "the question", but exactly how the thing is put together. Not a bad piece of information, if one is going to build a model of it.
( or....a pretty good story for why it was modeled that way )
We always learn far more from our own mistakes, than we will ever learn from another's advice.
The greatest place to live life, is on the sharp leading edge of a learning curve.
Lead me not into temptation.....I can find it myself!
The greatest place to live life, is on the sharp leading edge of a learning curve.
Lead me not into temptation.....I can find it myself!