Concrete plastic shrinkage crack repair

We call these types of cracks plastic shrinkage cracks PSCs. Fixing the cracks As the slab ages, these cracks grow with continued stressful influences. They grow wider as the concrete experiences traffic, resulting in chipped, brittle edges.

And PSCs get longer during curing, settling of the slab, and natural expansion and contraction due to environmental conditions. A maturing crack will get longer over time until it reaches a wall, column or possibly when the stress gets reduced or eliminated.

A grout coat could help by filling the thin void. Grind, clean and fill them with a high-viscosity polyurea developed for this. Make sure to follow along the crack so that both sides are level, full and flush. Or, vacuum, fill with product, and shave using repair product in a color that blends in with the slab when polished. Note: the human eye will notice chased cracks even more than before the repair. Then ask yourself and the owner some questions.

By doing this, everyone involved is satisfied and gets paid. Does the crack repair need to be decorative? Did something external cause the crack to form? How much and what type of traffic does this area incur?

Is this area either heaved or sunk compared to the rest of the slab? What is the width of the crack? The deeper the section the greater the chances for settlement. They are different from plastic shrinkage cracks by their distinct pattern which typically mirrors the pattern of the restraining elements such as the reinforcement. They tend to roughly follow the restraining element like reinforcing bars, or changes in the concrete section.

They can be quite wide at the surface, tend to extend only to the reinforcement or other restraining element and taper in width to thatlocation. In exposed situations, plastic settlement cracks may increase the risk of corrosion of the reinforcement and pose a threat to durability. What are the practices to be followed to minimise the risk of plastic settlement cracking? He is involved in more than consultancy projects for various Government, Public Sector and Private agencies, including Defense and Nuclear departments.

Sign in. Log into your account. Privacy Policy. Sign up. Password recovery. Friday, January 14, Forgot your password? Get help. Create an account. Constro Facilitator. The expectations from union budget The critical condition exists when the rate of evaporation of surface moisture exceeds the rate at which rising bleed water can replace it.

Water receding below the concrete surface forms menisci between the fine particles of cement and aggregate causing a tensile force to develop in the surface layers. If the concrete surface has started to set and has developed sufficient tensile strength to resist the tensile forces, cracks do not form.

If the surface dries very rapidly, the concrete may still be plastic, and cracks do not develop at that time; but plastic cracks will surely form as soon as the concrete stiffens a little more. Synthetic fiber reinforcement incorporated in the concrete mixture can help resist the tension when concrete is very weak. Conditions that cause high evaporation rates from the concrete surface, and thereby increase the possibility of plastic shrinkage cracking, include:.

Small changes in any one of these factors can significantly change the rate of evaporation.