Expansion Joint and Joint Sealant Glossary Index:

- Adhesion in Tension

- Blockout

- Compression Set

- Continuity of Seal

-  Expansion Joint

- Nosing Material

- Non-Invasive Anchoring

- Split Slab

- Sound Transmission Class (STC)

- Thermal Shock

Expansion Joints--Terms and Terminology: Thermal Shock

Thermal Shock--The rapid opening or closing of an expansion joint gap as the result of abrupt temperature change. The abrupt change causes the rapid shortening or lengthening of the structure on either side of the expansion joint causing a rapid cycle of compression or extension in the joint material. Thermal shock can result from the passage of a fast moving rain storm that rapidly cools a sun-baked structure on a hot summers day. Can also result from abrupt seasonal temperature changes particularly in spring and fall. Materials used in sealing structural joints subject to thermal shock must be capable of handling the resulting rapid cycling while remaining bonded to the substrates and while preserving watertightness.