Hot weather in southern England recently forced the cancellation of a number of train services. Basically it seems the track designers did not design the tracks to take the temperatures which have been experienced this year, leading to greater than expected extension of the rails, and so to rail buckling.
Higher temperatures may be a permanent feature of the UK climate. If so, it looks like rail tracks may have a long-term design problem, and one which would take a large amount of money to put right. Other infrastructure might have a similar problem. For example, perhaps structural engineers have similarly under-designed the expansion joints in bridges.