Concrete is a very solid, sturdy material; it’s not made to move. However, concrete can shift due to temperature-related shrinkage and expansion. Concrete can also move due to the structure on top of it shifting.
Concrete Expansion Joints
To prevent the damage shifting concrete can cause, Concrete Expansion Joints are incorporated into the concrete. Expansion joints can be used in walls, foundations, roofs, and paving. Expansion joints allow for contraction and expansion due to temperature changes. Likewise, the expansion joint can safely absorb the expansion and contraction of structures, as well as allow for shifting soil due to earthquakes.
The expansion joint gap is determined by the type of concrete slabs, such as a carport, sidewalk, floating slab floor, or a building foundation. It also depends on the type of concrete, the slab dimensions, and the reinforcement used. The depth of the expansion joint is generally at least a quarter of the slab thickness.
Before preparing the site for pouring the concrete, the placement of the expansion joints in the slab must be planned. Each expansion joint is made by placing a flexible material, such as strips of polyvinyl, running along the joint length. Once the concrete is poured, grooves are made in the setting concrete to place the expansion joint material. The advantage of polyvinyl expansion joints is the material is easy to work with, durable, and attractive. Also, it can be used to replace rotting wood strips in driveways and patios.
Trim-a-Slab manufactures quality polyvinyl concrete expansion joints for home and commercial use.