Corrosive MENA Climate Conducive to Concrete Repair

    According to Markets and Markets, the global market size of concrete repair mortars is estimated to reach USD2.6 bn by 2021 at a CAGR of 7.7% between 2016 and 2021. Analysis of the concrete repair mortars market can be by type (polymer-modified cementitious mortars and epoxy-based mortars), by application method (manual, spraying, and pouring), by end-use industry (building & car park, road & infrastructure, utility industries, and marine structure) and by region (Asia-Pacific, Europe, North America, the Middle East & Africa, and South America).  

    The concrete repair mortars market is driven by the increased spending on repair and maintenance in the construction industry and rising trend of public-private partnership for repair and refurbishment of transport infrastructure. Concrete repair mortars; mainly polymer-modified concrete repair mortars are manufactured from various raw materials such as Portland cement, silica sand, additives, and polymer resins. These raw materials are supplied to the major concrete repair mortars manufacturers, such as Sika AG (Switzerland), Fosroc International Ltd. (U.K.), Saint Gobain Weber S.A. (Germany), Mapei S.p.A. (Italy), BASF SE (Germany), Pidilite Industries Ltd. (India), Adhesives Technology Corporation (U.S.), Flexcrete Technologies Ltd. (U.K.), Remmers Baustofftechnik GmbH (Germany), and The Euclid Chemical Company (U.S.). These manufacturers are focusing on increasing their geographical presence by undertaking strategies such as expansion and new product launch. According to the Big5 Hub, it will not take long to find requests for proposal covering the repair and protection of concrete. It has been well recorded that environmental factors in the GCC have an adverse impact on concrete structures. Thanks to a combination of high ambient temperatures, salt-contaminated dust, sea water and underground salts, the region has concocted a natural recipe for the gradual deterioration and destruction of concrete. 

    …the region has concocted a natural recipe for the gradual deterioration and destruction of concrete.

    It’s a challenge that has drawn considerable attention over the years as it became apparent that a large number of existing reinforced concrete structures in Dubai, and the UAE at large, are suffering from durability problems, leading to accelerated deterioration and cracking, thus reducing the functional service life. Typical issues concrete in the region faces include concrete spalls - where small pieces break away from the surface - delimitation and cracking. In addition, the corrosion of the steel rebar within concrete structures is also of particular concern. A lot of the worst affected buildings and structures are older builds and as such a core part of the process is regular monitoring of condition and the taking of prompt action when a problem emerges, in order to limit the extent of any damage. When you look at the reinforced concrete construction that took place in the UAE, there was a boom in the real estate sector and an awful lot of projects ongoing at the time of the financial crisis. A number of those projects were put on hold, so they were partially completed. But the building wasn't closed, the de-watering of the substructure elements was turned off, and the reinforced concrete could have been saturated in groundwater and aggressive chlorides. This has led to a host of durability issues for all of those projects that were put on hold. There's a number of those structures where corrosion of the embedded steel has occurred and it's likely that there will be corrosion in the future. In those situations you have to look at appropriate remedial works to the reinforced concrete, to ensure the durability. Remedial works could be doing patch repairs, where there has been corrosion of the steel and the concrete is cracking and failing. It could be done using some electrochemical techniques, if there is a high degree of aggressive salts, then the only way to really permanently ensure the durability of the reinforced concrete is to put impressed current cathodic protection system on the elements of the structure. That’s where you take an electrical anode mesh that you put a low voltage DC current through, and you send electric current through the concrete which is your electrolyte, to the steel reinforcement cage. You are changing the potential of the steel, to a level where it can't corrode. That's an electrochemical technique to control corrosion. Another similar technique is called desalination whereby you put a temporary electrical anode system within an electrolyte onto the faces of the elements of the structure and then you draw out the salts from the concrete with an electrical current over a period of six to eight weeks.

    ACW Staff