Concrete Remediation Newcastle – How to Deal With Concrete Flaws

Concrete is an amazing building material that is extremely durable and versatile when correctly designed, placed, and cured. Unfortunately, there are many things that can go wrong with this popular construction material.

Each situation requires a unique repair method. For example, repairing chemical damage at a service station will require a different approach than repairing it at a metal plating facility.

Causes of Damage

Even concrete that’s highly durable, low maintenance and relatively inexpensive can deteriorate, especially in a harsh environment like a coastal location. Leaving such a situation unattended can cost an organisation dearly in lost business as customers stay away from businesses with unattractive and potentially hazardous environments.

Reinforcement corrosion is a major cause of damage to concrete structures. When this happens, corrosive oxygen enters the concrete and reacts with the steel reinforcement to form rust that expands or degrades the surrounding concrete, increasing stress on the internal structure.

There are many reasons for corrosion, from mild acid damage – such as vinegar and red wine in bottle shop floors – through to heavy chemical attack – such as battery acid, alkaline liquids and some industrial oils. Other common causes are ground movement, incompatible support metals, stress fractures due to excessive weight and a poorly installed or aged waterproofing membrane. A full diagnostic is required to understand the cause and full extent of any concrete deterioration or damage and therefore what remedial works are needed.

Cracks

Concrete is a strong, durable construction material but is vulnerable to damage. Cracks can appear for many reasons, including excessive temperature changes, ground movement and excess water in the mix.

Early-age cracking is not considered to affect the overall safety of concrete structures, however it can have an adverse impact on the visual appearance. It can also act as a passageway for water, oxygen and minerals which may lead to the corrosion of reinforcement steel, deterioration of concrete and spalling if not addressed.

Cracks should always be inspected and diagnosed by a qualified professional to determine their severity, cause and whether they are dormant or active. Once this has been established, a suitable repair method can be determined – this may include V-cutting and sealing with epoxy or polyurethane. In some situations, concrete surface protective coatings or crack injection can be a more appropriate solution. This involves injecting a waterproof epoxy or polyurethane into the crack to stop moisture ingress and maintain the structural integrity of the structure.

Popouts

Popouts are a surface blemish that develops when an aggregate particle expands and fractures the surrounding concrete. They are usually small and cone-shaped. These surface defects are not harmful and do not affect the structural serviceability of concrete slabs. However, they are aesthetically unappealing.

The best way to mitigate aggregate popouts is to use aggregates that are low-alkali or non-reactive. Unfortunately, this may not be practical in many regions. Even when the aggregate meets MnDOT or ASTM specifications for concrete pavements, it can still be prone to this problem. This is because natural aggregate deposits often contain shale, iron oxide particles, and other deleterious materials.

Using the right concrete mix design is another way to reduce the frequency of aggregate popouts. This includes reducing the water-to-cementitious material ratio, allowing longer curing times for exterior flatwork, and using Class F fly ash or slag cement as partial cement substitutes to reduce permeability and mitigate alkali-silica reaction (ASR). These measures can also lower the amount of swelling pressure on the coarse aggregate particles.

Curing

Concrete is one of the most utilised materials in history but, like any material, it has its flaws. These problems are not only unsightly and costly to repair but they can also place lives at risk. It is vital that the underlying causes of these issues are corrected.

This will not only stop the concrete from continuing to deteriorate but it will also protect the structural integrity of the structure. A concrete remediation contractor can use a polyurethane concrete sealant to fill these cracks and help to prevent further damage.

Popouts are a bit different from cracks because they are smaller imperfections. They usually appear on slabs where the surface has been broken up or damaged and they can be caused by many factors. These include poor design, incorrect pouring, bad workmanship, air pockets, a lack of proper curing and chemical attack. These can all be fixed by a skilled concrete remediation expert. This can be done using hydrodemolition, a technique that uses high pressure water to remove the concrete without compromising the sound concrete around it.

from Origin Concrete Newcastle https://ift.tt/J3fXzZL
via IFTTT