On buildings like walkways, roadways, and bridges, expansion joints are frequently found. A mid-structure separation intended to unite objects, absorb vibration, or permit movement is called an expansion joint. When temperatures fluctuate, expansion joints in buildings can help absorb the expansion and contraction of concrete slabs.

Concrete can crack or distort if expansion joints aren't used. On the other hand, expansion joints might malfunction on their own. Incompressible materials that lock joints and create stresses that can lead to concrete spalling or shattering are a big problem. Therefore, expansion joints usually have seals fitted in order to keep incompressible debris out of the joint. Strip seals and compression seals are the two forms of common seals.