Concrete is one of the most common building materials today and chances are you will find it in almost every home or building. But if it’s not laid correctly, concrete becomes prone to concrete cancer, and this can be a serious condition necessitating repairs. Concrete cancer occurs when the steel reinforcing within a concrete slab begins to rust. When this happens, steel expands causing the concrete around it to delaminate and flake away. It is important to have concrete cancer addressed before it accelerates and causes further cracks on the building.
Causes of concrete cancer
Concrete cancer occurs when steel rusts and expands within the concrete slabs. Various factors contribute to the wearing out of steel and subsequent delamination and cracking of concrete. They include the following:
- Poor workmanship during construction, resulting in poor treatment of reinforcing steel during the pouring of concrete.
- The installation of reinforcing steel with inadequate concrete cover. As rainwater seeps through the concrete, it reaches the steel which is close to the surface. The water reacts with steel to cause oxidation which occurs in the form of rust.
- Using incompatible reinforcing metals in proximity to each other. If they come into contact, they cause a chemical reaction which can trigger rusting.
- Poor installation of window and door lintels causes exposure to elements of weather, which results in rusting.
- Fractures or wearing out of concrete which allow water to seep through the concrete and react with the reinforcing steel to trigger rusting.
Signs of concrete cancer
Various signs indicate a building has concrete cancer. The most common ones you need to look out for are as follows:
- Localized brown discoloration on the surface of the concrete. It is usually one of the earliest signs of steel rusting.
- Concrete with a rough and flaky surface. It may also be pitted.
- Cracks in concrete with some chunks falling off the surface.
- The appearance of leaks in the roof or internal walls of the building.
Often people mistakes these signs for general weathering or dilapidation caused by elements of weather. While such factors may play a part in exacerbating the problem, the underlying issue lies within the concrete.
How to address concrete cancer
If you notice any brown stains and cracks on your wall, concrete floor, or roof, it is important to contact a construction contractor for immediate repairs. The repair process usually involves removing all dummy concrete and rust from steel. After this, an anticorrosive is applied to the steel and fresh render on the concrete to restore the original look. Waterproofing may also be necessary to prevent ingress of moisture into the concrete.
Concrete cancer compromises the integrity of buildings. Once detected, it should be addressed immediately to avoid further damage which could cost you more money.Read More