Concrete Repairs- Dorset
Newman’s are a Concrete Repair specialist and our services have been utilised on a 12 months JCT works contract to a residential site in West Bay, Dorset in order to repair concrete which had failed caused by chloride attack.
Chloride attack had caused extensive cracking to this reinforced concrete block of residential properties putting the structure into high risk of further structural issues as well as water ingress. As well as structural defects and water ingress falling concrete poses a severe risk to the health of the residents and passers-by and required immediate attention.
Chloride Attack poses severe threat to the integrity of reinforced concrete structures and particularly those in marine environments such as this block being only 30 metres from the sea front. Chloride Attack occurs when salts and other contaminants are absorbed by porous concrete. A chemical reaction then occurs within the concrete that causes hydrochloric acid that eats away at the steel causing the steel to corrode and expand spalling the concrete.
Catastrophic loss of structural integrity can occur as a result of chloride attack and it is essential that marine structures are protected as best possible to prevent chloride attack occurring. Porous concrete will suffer at an enhanced rate as opposed to concrete with pores which are small and any surface defects such as minor cracking or spalling can lead to severe problems.
In this instance chloride attack had caused major spalling and in some areas the concrete had blown away so much so that all of the reinforcing rods were exposed accelerating the rate of attack leading to severe concrete failure.
Our surveyors designed a suitable repair solution using the Flexcrete concrete repair system in order to repair the corroded steel and reinstate the areas of spalled concrete. By breaking out the failed concrete and exposing the steel we were able to treat the steel by abrasive blasting to remove all corroded steel.
In order to treat the corroded steel a 20mm coating of Flexcrete steel reinforcement protector was applied around all of the corroded steel which will prevent Chlorides from attacking the steel. Due to the concrete being fairly porous Flexcrete bonding bridge slurry was applied to the existing concrete to provide a good bond between the existing concrete and new repair mortar.
In some instances the repairs to pillars and beams were in excess of 150mm deep and Flexcrete Monomix excelled in overhead repairs allowing us to carry out a fast and effective repair. With the steel treated and the repair mortar installed we used Flexcrete monolevel fairing coat mortar to seal all pores within the new repair mortar and provide a smooth flush finish ready for decoration.
Flexcrete Anti carbonation coatings were then applied in order to provide a decorative finish but also to protect the concrete. Flexcrete’s monodex ultra is a high performance coating that resists carbon attack and aids in the prevention of chloride attack.
With a system solution we were able to provide a 10 year guarantee on to the areas of repair covered by the manufacturer and also our own independent insurance backed guarantee.
Newman’s can help to diagnose structural defects, cracking and movement by arranging a free Structural Survey, contact London and the south East’s leading structural repair specialists for Help, Advice and peace of mind Call 0333 444 0154 or Email info@newmans.com