| Comment | Concrete has a lifespan ultimately. I know this more from a building perspective, but it's the same. Water slowly seeps into the concrete, bringing carbon dioxide from the air. This very slowly turns the concrete, which is a strong base material (aka high pH level), acidic. This affects the steel within the concrete, causing it to corrode and expand. Now the concrete is under stress from itself, and because the steel is failing it cannot deal with tensile stresses as well (concrete is amazing at compressive force resistance, but shit under tension, hence the inclusion of steel reinforcement). This will cause cracking, which leads to more water ingress, which accelerates things.
I suspect the bridge either wasn't checked that often, or well enough, so wasn't in their radar, then didn't a car hit or crash on the ramp, likely exposing how bad the structure was, or someone finally noticed it and went ..oh shit... |
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