Curling Concrete Floor

Reinforcing steel placed near the top surface of the slab can help restrain curling.

Curling concrete floor.

Both the canadian standards association csa and the american concrete institute aci recognize that control of curling is a designer responsibility. The american concrete institute. The best time to pour concrete is when temperatures are expected to remain above 50 degrees for five to seven days but plans can go awry with the arrival of. The occurrence is primarily due to differences in moisture and or temperature between the top and bottom surfaces of a concrete slab.

Placing 4 bars on 18 inch centers both ways and chairing the bars to keep them within an inch of the surface has been suggested see controlling curling and cracking in floors to receive coverings concrete construction july 1998 pp. If the total curl is less than 1 4 inch or curling occurs primarily in low traffic areas or under storage racks the owner can often live with it provided that cracking isn t excessive. Written by ramon planas masip. 09 january 2019 posted in concrete placing inforce fibre slab design fibre reinforcing technical information.

Curling is a phenomenon that occurs in concrete slabs lifting the edges of them and causes problems such as. As a new concrete floor dries during the first year surface tension caused by this drying of the concrete creates shrinkage and more specifically a lifting or curling of the floor at all floor joints. N stepping at joints curling of adjacent panels may result in stepping ie a variation in the. Curling is the distortion of a slab into a curved shape by upward or downward bending of the edges.

Page 4 of 6 curling of concrete slabs if the curling had not been highlighted by the cracked brickwork joints it would probably not have been evident as the extent of curling is within typical floor construction tolerances for residential buildings. This occurs primarily due to differences in moisture and or temperature between the top and bottom surfaces of a concrete slab. Data from floor slabs indicates that tolerances losses from curling can result in up to a 50 reduction in tolerances that were originally. Founded in 1904 and headquartered in farmington hills michigan usa the american concrete institute is a leading authority and resource worldwide for the development dissemination and adoption of its consensus based standards technical resources educational programs and proven expertise for individuals and organizations involved in concrete design.

When concrete slabs on grade curl the curling sometimes has little effect on floor performance. Curling in concrete floors causes consequences and solutions. Curling is the distortion of a slab into a curved shape by upward or downward bending of the edges. There are occasions however when curling isn t tolerable and repairs are needed.