An expansion joint is an assembly designed to safely absorb the heat-induced expansion and contraction of metallic parts. They are commonly found between sections of sidewalks, bridges, railway tracks, piping systems, and other structures. In physics, thermal expansion is the tendency of matter to increase in volume or pressure when heated. ... A sidewalk (North American English), or pavement or footpath (Commonwealth English), is a path, usually constructed of concrete (particularly in the United States, and Canada), asphalt, brick (particularly in Europe) or stone, designed for pedestrian traffic and often running alongside a road. ... A log bridge in the French Alps near Vallorcine. ... track Rail tracks are used on railways (or railroads), which, together with railroad switches (or points), guide trains without the need for steering. ...