In addition to reading about repairing concrete shrinkage cracks if crack repair is needed at all.
Shrinkage cracks in concrete slab.
Concrete slab drying shrinkage cracking can be the unfortunate end.
Shrinkage cracks in a slab photo above are unlikely to be of any structural concern but can be a source of water entry or radon entry in buildings and may form a tripping hazard.
Contraction joints or control joints when cracked are really just straight shrinkage cracks.
Most of this excess water begins to exit the concrete during placement curing and causes the concrete to shrink.
This restraint creates tensile stresses in the concrete slab which in turn may produce drying shrinkage cracking.
Shrinkage cracking can be managed by the use of control joints placed in the slab.
While shrinkage in poured concrete walls or floor slabs is a normal property of curing concrete shrinkage cracks can be controlled or where they have occurred in some cases repairs are needed.
Most of the water will eventually evaporate causing shrinkage of the concrete slab.
As the concrete slab dries after placement it shrinks.
This is the main cause of concrete shrinkage cracks on drying.
When concrete is mixed more water than is needed for hydration is mixed with the dry components such as sand cement and an aggregate.
Plastic shrinkage concrete cracks when concrete is still in its plastic state before hardening it is full of water.
Similar uncontrolled or random cracks sometimes due to poor joint layout meander across the surface.
These cracks are comparatively short cracks.
When the evaporation of the moisture at the surface of concrete is more than the availability of the rising bleed to fill the surface moisture if this process happens before concrete attaining its tensile strength the volume change may cause cracks.
Concrete and mortar are porous in their structure in the form of inter molecular space.
Plastic shrinkage cracks are common in slabs.
Shrinkage cracks in concrete occur due to change in moisture of concrete.
When that water eventually leaves the slab it leaves behind large voids between the solid particles.
See details at concrete shrinkage cracks.
