Question

Explain how engineers build bridges and concrete road surfaces for expansion and contraction.

Answer 1

Take e.g railway tracks, there are built outta steel which expands faster during summer and contracts during winter, if it would really happen the trains must go wrong track. So the engineers overcame with this problem by connecting two rods to another rod which contains a gap, so when it expands it might not be a problem filling the gap, if it contracts that too might not be a problem cuz it was already fixed to rod.
like this all constructions are made