In order to avoid concrete structures from damage triggered by plastic shrinking, thermal shrinking, settlement, motion … concrete joints are needed.
There are 3 typical kinds of concrete joints as laid out bellows.
1. Contraction (Control) Joints.
Contraction Joints are intentionally set up joints created to manage splitting that may otherwise take place due to the inescapable, frequently unforeseeable, contraction of concrete.
These joints are frequently called control joints because they are planned to manage fracture areas. The essential aircraft of weak point might be formed by decreasing the concrete cross-section by tooling or saw cutting a joint within 24 hours of positioning.
Contraction joint motion is expected to be little.
2. Building and construction Joints.
Building and construction Joints are made before and after disturbances in the positioning of concrete or through the positioning of precast systems.
Areas are typically predetermined so regarding restrict the work that can be done at one time to a practical size, with least disability of the completed structure, though they might likewise be demanded by unexpected disturbances in concreting operations.
Depending upon the structural style, they might be needed to work later on as growth or contraction joints, or they might be needed to be peacefully bonded to the very first so regarding preserve total structural stability.
Building joints might run horizontally or vertically depending upon the positioning series recommended by the style of the structure.
3. Growth Joints.
Growth Joints are created to avoid the squashing and distortion of the abutting concrete structural systems that may otherwise take place due to the transmission of compressive forces that might be established by growth, used loads, or differential motions emerging from the setup of the structure or its settlement.
Growth joints are made by offering an area over the whole random sample in between abutting structural systems. Growth joint motion might be high (approximately 30 % of joint width).