Concrete joint sealants and joint fillers are different in both chemical formulation and intended use. Elastomeric Joint Sealants are cold-applied elastomeric single or multi-component materials used for sealing, caulking, or glazing operations on buildings, plazas, and decks for vehicular or pedestrian use, and types of construction other than highway and airfield pavements and bridges. The primary purpose of a joint sealant is to keep water, dirt, and debris out of the joint. Designed to be able to expand and contract along with the joint, sealants are relatively soft and flexible materials, typically polyurethane, silicone, or acrylic in composition.
Hard-wheeled vehicles, carts, and pallet jacks traveling over a sealant-filled joint will cause it to deflect, leaving the edges of the joint unprotected. Leading to edge cracking and spalling.