Why do sidewalks always have lines cut across them every few feet?
In: Engineering
Concrete (well, literally any material) will expand when it gets hotter and contract when it gets colder. This combined with water freezing and unfreezing will cause cracks to form in said material if it is a single ridgid piece.
The lines break up the concrete and allow it to expand/contract. So the sidewalk lasts longer.
They don’t do this in roads because bumps are really bad there. Not so much on a sidewalk.
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