5 Most Common Concrete Problems with New Concrete in Edmonton

As with other building materials, concrete will degrade over time and may need to be cut out and removed but there are ways to slow wear and fix damages. Identifying an issue and responding quickly is key, so you should perform routine inspections and contact a reliable concrete company for crucial repairs. The following list covers common concrete problems and the associated solutions that can preserve your structure’s appearance and stability.

1. Discoloration

Light or dark patches on new concrete can result from improper installation techniques or stains from materials such as automobile fluids and cleaning chemicals. It is imperative to address this damage as soon as you notice it to keep the discoloration from migrating across the entire slab of concrete.

Some option to deal with this issue are as follows:

• Scrub the concrete with a stiff brush dipped in a diluted vinegar solution to restore its appearance and halt the progression of this problem.
• In certain situations, stronger chemicals such as hydrochloric acid or diammonium citrate may be needed to resolve severe cases of discoloration. Sometimes these solutions have been known to make problems worse if applied incorrectly so it is a good idea to consult a concrete expert before using them.

2. Cracks

Cracks in concrete tend to start at the surface and work their way to the bottom of the slab over the course of several months. If you allow the cracks to reach through to the subgrade, you will need to fully replace the concrete structure to restore its strength and appearance. You can easily fix small cracks by cleaning loose material out of the damaged areas and filling the spaces with concrete filler. Applying a sealant product after the patch cures will help strengthen the repaired area.

How to reduce cracking of concrete:

• Remove topsoil, soft spots and organic material in the subgrade
• Compact all loose soil underneath the concrete slab
• Slope the subgrade for proper drainage
• Design a flexible concrete pavement that could accommodate load and movements
• Install concrete joints accordingly by sawing, forming or tooling a groove
• Place, finish and cure concrete accordingly depending on the weather conditions
• Do not finish concrete if it has not finished bleeding
• Do not overwork concrete surface
• Avoid rapid drying conditions or use a set retardant admixture
• Minimize the mix water content by maximizing the size and amount of coarse aggregate and use low-shrinkage aggregate

3. Scaling

As expected, Edmonton has some harsh winter weather.  The use of de-icing products on your concrete during winter months may cause signs of scaling or pitting. Damaged areas need to be repaired quickly otherwise the loss of surface material will usually continue. The solution for this issue is a new layer of resurfacing concrete, which will require you to rough up the entire surface of the concrete structure to prepare it for the repair process. After you have applied the new layer of concrete and allowed the material to cure overnight, you should apply a waterproof finishing treatment to protect it further.

How can concrete scaling be avoided:

• Use a low slump-air (6 to 7 percent) in the entrained mix
• Wait until water has been evaporated from the concrete surface
• Do not use salt or other chemicals during the winter season. The best de-icer for concrete is calcium chloride. Calcium chloride will melt snow and ice on concrete in temperatures as low as -32 degrees Celsius.

4. Crazing

A network of tiny cracks in the surface of concrete is referred to as crazing. Crazing often occurs due to improper mixing or curing during the installation process. Although these cracks do not extend down far enough to impact structural stability of the concrete, the fine lines may reduce the aesthetic value of your property. An experienced concrete company can prevent crazing through a quality installation process but it may be possible to cover up this type of damage if you cannot proactively avoid it. If the crazing occurs on a decorative indoor concrete structure, you may be able to apply a layer of epoxy paint to cover up the unsightly cracks. Unfortunately, sealers and surface hardeners can make the cracks more noticeable, so a layer of resurfacing concrete is often the only option for concealing crazing on outdoor structures.

How to avoid crazed concrete:

• Cure the concrete in a timely manner
• Use a moderate slump concrete without bleeding and segregation
• Do not finish concrete until all water has evaporated
• Do not dust dry cement on the surface while water is present
• Do not sprinkle water over the concrete while finishing it
• If the weather could produce high evaporation rates, spray some water onto the subgrade, so it will not absorb the water from the concrete mix

5. Buckling

If you have large trees on your property, the roots may grow under your concrete structure, causing the slab to buckle and split apart. Edmonton experiences extreme freeze-thaw cycles as well as heat exposure and this can also cause the concrete to buckle. The only way to repair this type of damage is to remove the damaged portion of the concrete, along with any roots that may have caused the problem. You can then install a large patch to prevent the buckled area from causing adjacent structures to crack and split as well.

When it comes to the issues with tree roots causing your concrete to buckle, there are a few things that you can consider:

• Install root barriers before the roots reach the concrete.
• Cut the roots and dam them with root barriers to prevent further growth.
• Cut down the tree and remove the root system so you can make a smooth, level surface again.

With any of the above noted issues we recommend contacting a concrete professional.  In some situations, you may need to cut and remove sections of your concrete.

For any advice related to concrete issues resulting in cutting or removing, contact Michael at Walser Contracting Ltd!