Cons for Concrete Vertical Construction Joints

Different Types of Joints

• Types of concrete joints include both vertical and horizontal joints, expansion joints which are used to permit both expansion and contracting of concrete, contraction joints and crack prevention joints. Expansion joints use encased rebar in large volumes of concrete to hold concrete gaps together so that the concrete will be able to expand or contract without causing undue stress to the concrete. Contraction joints however, only provide room for the concrete to contract. Because crack prevention joints are incapable of actually preventing cracks they are commonly used to cause cracking to appear in a predictable way. This allows workers to prepare to fix cracks before they happen.

Joint Uses

• Properly used joints will gently reinforce a wall to prevent cracking, slipping and damage due to any natural causes. Correctly constructed joints will be evenly spaced through a wall in order to strengthen the wall and avoid causing stress of any kind. However, if improperly spaced, the joints can actually cause the cracking and structure stress they were intended to prevent.

Expansion

• Vertical Concrete Joints act as physical gaps between one section of concrete and another while tying the section together with metal reinforcements. Because concrete expands when it gets wet, this can cause structural weakness during expansion. A construction joint without the proper metal reinforcements and spaces will cause the concrete to stress and possibly fracture.

Contraction

• Concrete contracts as it dries, which means that the concrete between two vertical concrete joints may contract and pull away from the joints. This causes immense structural problems due to instability and can even create the hazard of falling concrete or an insecure structure.

Cracking

• All concrete is liable to crack due to the fact that it contracts and expands during different weather or while drying. If workers assemble a concrete joint correctly with metal casings to allow concrete movement, it can help to avoid these cracks. However, in some cases, the joint can increase cracking factors since it does not allow the concrete to move or because it has been placed in an area that will cause stress to the panel of concrete.