Where does this come from, and can I check it?

Steel and concrete grow longer when warm, so joints absorb the movement. The figure is taken from NIST, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.

Is this really a science fact?

Yes. It sits on the Science shelf, one of 2,600 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.

What else can I read about it?

The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.

Mondo Knows Facts

Bridges need gaps for thermal expansion

Steel and concrete grow longer when warm, so joints absorb the movement Most materials expand as their atoms vibrate more vigorously and take up slightly more space. A steel rail expands by roughly twelve parts per million for each degree Celsius it warms. Expansion joints and slotted rail fixings stop long structures from buckling in summer heat. It sits in Mondo's science collection, one of 200 facts that each trace back to the reference below.

Where this comes from

NIST

Facts that can change over time are reviewed and updated. If something here looks wrong, Mondo would rather know than be confidently incorrect.

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Tags: physics, materials, engineering

Bridges need gaps for thermal expansion: the short answers

Where does this come from, and can I check it?: Steel and concrete grow longer when warm, so joints absorb the movement. The figure is taken from NIST, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
Is this really a science fact?: Yes. It sits on the Science shelf, one of 2,600 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.
What else can I read about it?: The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.