Why Railroads Don’t Need Expansion Joints
A friendly overview of thermal effects on railways.
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Errata: At 9:00, the left column of calculations is incorrectly labeled “SI.” It should be imperial. Whoops!
Just as all materials have a mostly linear relationship between temperature change and length change, all materials also have a similar relationship between stress and change in length (often called strain). And this is part of the secret to continuous welded rail: restrained thermal expansion. You can overcome one with the other.
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This is not engineering advice. Everything here is for informational and entertainment purposes only. Contact an engineer licensed to practice in your area if you need professional advice or services. All non-licensed clips used for fair use commentary, criticism, and educational purposes.
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