how do you prevent concrete walls from crackng?

Answer 1

Concrete will almost always crack, there is just too much settling and shrinking involved for something that rigid and brittle not too. If you can help it cure more slowly it helps, if it's hot out keep the concrete wet down and cooler until dark. Concrete creates heat due to the chemical reaction taking place that causes it to harden, so it can get really hot on a warm sunny day while it's trying to cure. Best thing is to use the fibered concrete or add steel mesh to it to prevent seperation when the concrete does crack. And expansion joints usually allow the settling and shrinking while keeping the cracking to the lines where the joints are.

Answer 2

Use rebar And don't let the concrete set too fast, ie on a very dry day, use a fine mist to keep concrete cool. If the wall is already poured and set, you have to relieve the stress that is causing the cracking (usually water pressure, from ground water). It is also possible that the concrete simply can not take the load it is bearing. However this is not too likely if built to the building code specifications.

Answer 3

I dont think you are refering to cracks caused by building too early on foundations or by bull dozing soil around the newly poured basement walls. That is problem that arrises mostly in new home construction.

Cure rate is the key here in walls. The Hoover dam has pipes within it that large quantities of water were pumped to remove heat from the chemical action of the curing concrete. Not a single crack is allowed in Dam construction. The walls of hoover dam are over 35 feet across and a few hundred high.

Cure of concrete, of course, is a chemical reaction involving the capture of water itself into the concrete and generates heat in the process. Removal of the heat is the key here.

As far as sidewalk cracks are concerned, those are due mostly in part of setting of the ground beneath as the concrete begins to set up. One can eliminate those almost in entirety by soaking down the pouring area with water a few times in a week before the sidewalk or garage floor is poured. This will sturdy up the sub base and virtually eliminate those cracks.

Saw cuts of course are a key way to control cracks either caused by shrinkage at cure or settling.

One can have cracks in concrete poured basements permanently fixed by companies that literally inject liquid epoxy into the crack and rebond the concrete at the crack. This method has been tested fully and the strength of the bond is greater than the original concrete. Concrete basements of course, have steel rebar in them, so cracks even though visible arent structural problems. They might present leaks, in cases where insufficient pea gravel was used around the concrete walls, otherwise there is no reason to repair them with the epoxy method or any other method.

Answer 4

joints