Share Funny Videos, Images, Memes, Quotes and more

Thanks for sharing this was an interesting question I never stopped to consider! To summarize, the footing at the ties creates equivalent mechanical strain that counteracts the strain caused by thermal expansion. Since steel can handle a certain limit of strain without permanently deforming, this does not cause permanent damage. The strain limit for most steel is an order of magnitude greater than the strain produced by a 100 K change in temperature.