Why Does Concrete Crack?

Posted on 28th February 2018 by Ever Readymix Concrete

Concrete is known to crack for many reasons and whether it cracks immediately, during the curing process, or years after the pour, you want to do all you can to prevent it cracking any further. To answer a question many concrete specialists are asked, we’ve put together this article detailing every reason that your concrete might crack.

To minimise the chances of your concrete wearing prematurely, we recommend having your concrete mixed, delivered and poured by a professional readymix company, like Ever Readymix.

 

Crazing Cracks

Crazing cracks are hairline cracks that resemble spider webs and form on the surface of the concrete. It is caused by a premature drying of the slab. If the water on the surface of newly poured concrete dries quicker than it should, then crazing is likely to form. There is nothing to worry about with crazing cracks though as they are minor aesthetic defects. They can be repaired, however the concrete is just as strong with or without crazing.

 

Heaving Cracks

Heaving cracks refer to major structural cracks in a slab that are caused by movement from beneath the concrete. This movement can come from many sources, including earthquakes, tremors and subsidence. The most common cause, of course, is tree roots. The slow but steady progress of tree roots forces the concrete to rise and crack. It is seen regularly in gardens and on the pavements of streets lined with trees. It’s a tough type of crack to avoid as it’s typically dictated by natural causes. However, it has been known for burst water pipes to cause the same type of crack.

 

Pressure Cracks

When a slab is professionally poured it has been specified to withstand a certain amount of weight being placed upon it. If something that exceeds this weight is placed upon the concrete (typically a large vehicle) then this will cause a pressure crack. Pressure cracks sometimes form long after a weighty vehicle has driven over the slab. This is because the weight has altered the ground below the slab which creates pressure points that gradually cause the slab to crack.

 

Settling Cracks

Settling cracks are the opposite to heaving cracks. They are caused by movement beneath the concrete that falls under the category of ‘settling’. Either because a tree has been removed near to the concrete, and the roots have subsequently decomposed, or wiring and plumbing has shifted or settled beneath the slab. Settling cracks can be caused by geological factors, too, such as in mining areas where coal seams and shafts deep underground shift or collapse.

Ever Readymix supply concrete for commercial and domestic customers in Yorkshire, including Barnsley, Doncaster, Goole and York. No matter what your needs, our team are fully equipped to mix the perfect batch of concrete for your project and use a range of methods to deliver to site, using our fleet of trucks and concrete pumps. We even offer free site surveys and weekend delivery by arrangement, making us the number one choice for customers in Yorkshire. Contact our team today to find out more about our services or arrange a free survey.