Product Overview

MC-Dur 1000 addresses the most widespread durability mechanism causing premature deterioration of reinforced concrete buildings and structures in India: carbonation-induced corrosion of reinforcement. In the Indian context, carbonation is the dominant cause of concrete structural deterioration in urban environments — including Delhi, Ghaziabad, Noida, and Uttar Pradesh cities — where atmospheric CO2 concentrations (0.04 to 0.08 percent in urban areas, 2 to 5 times higher than rural background) penetrate concrete from the exposed surface at a rate proportional to the square root of time (the carbonation depth increases as the square root of age in years), progressively reducing the pH of the concrete pore water from the protective alkaline level (pH 12.5 to 13.5 in uncarbonated concrete) to the corrosion-promoting level (pH below 9 to 10) at the depth of the reinforcement. For typical residential and commercial building concrete in India (C20 to C30 grade, 20 to 25 mm nominal cover depth, w/c 0.50 to 0.60), the carbonation front reaches the reinforcement in 15 to 25 years in urban environments — after which steel depassivation, corrosion initiation, and eventual spalling typically occur within 5 to 10 additional years; this 20 to 35 year service life before major maintenance is far below the 60 to 100 year design life expected of RC buildings and the 100 year design life of bridges and infrastructure. MC-Dur 1000 applied to the concrete surface as a protective coating creates an additional CO2 diffusion barrier that, at the specified 100 to 200 micron dry film thickness, provides an equivalent air layer resistance of 50 to 100 metres — equivalent to approximately 5 to 10 metres of additional concrete cover (which would require 5 to 10 times the existing concrete cover to achieve the same CO2 barrier by concrete alone); this dramatically extends the time before carbonation reaches the reinforcement and substantially delays the onset of corrosion and spalling. The practical significance in Delhi NCR is large: approximately 500,000 to 800,000 multi-storey residential and commercial buildings constructed between 1975 and 2005 are currently in the 20 to 50 year age range where carbonation-induced corrosion is beginning to manifest as concrete spalling on balconies, facades, columns, and beams — and the application of MC-Dur 1000 to these buildings is both a preventive measure (on buildings with 15 to 25 mm carbonation depth but not yet corrosion-active reinforcement) and a protective measure applied after MC-RocTec repair (on buildings where corrosion repair has been carried out and a coating is needed to prevent re-carbonation of the repaired areas). Space Arc Engineering supplies MC-Dur 1000 for building maintenance and protection contracts, bridge and flyover maintenance, and parking structure protection in Ghaziabad, Noida, Delhi, and Uttar Pradesh.

Applications

• Preventive anti-carbonation coating on residential and commercial building exteriors in Delhi NCR — application of MC-Dur 1000 to the concrete column faces, beam soffits, slab edges, and external wall surfaces of multi-storey residential and commercial buildings in Delhi, Ghaziabad, Noida, Gurgaon, and Faridabad as part of a preventive asset maintenance programme applied at 15 to 20 years after construction before carbonation reaches the reinforcement depth; the most valuable preventive application window is when the carbonation front is at 10 to 20 mm depth (measurable by phenolphthalein indicator on a freshly exposed concrete surface — the boundary between pink, non-carbonated concrete above pH 9 and colourless, carbonated concrete below pH 9); at this carbonation depth, the reinforcement at 25 to 30 mm cover is still in the uncarbonated zone with an intact passivating layer and no corrosion has initiated; applying MC-Dur 1000 at this stage halts further carbonation progress and indefinitely preserves the reinforcement in the passive, non-corroding state for the remaining 40 to 80 year design life
• Protective coating on multi-level parking structures after concrete repair — application of MC-Dur 1000 as the standard protective coating over the full exterior concrete surface of multi-level car parks, parking decks, and underground parking structures in Delhi NCR after completion of concrete repair works (corrosion repair with MC-RocTec structural mortars and MC-Nafufill BF bonding agent) to prevent re-carbonation of the repaired areas and protect the full parking structure concrete surface from future carbonation, chloride ingress (from vehicles tracked in with road de-icing salt in Delhi NCR winters), and water ingress; parking structures are one of the most challenging durability environments for concrete (vehicle exhaust CO2 enrichment, de-icing salt, thermal cycling, and moisture cycling) and one of the most cost-effective applications of MC-Dur 1000 because the coating prevents the next cycle of expensive concrete repair within 10 to 15 years
• Bridge and flyover concrete protection in Delhi NCR and UP state highway maintenance — application of MC-Dur 1000 to concrete bridge piers, abutment walls, pier caps, and deck soffit surfaces on the large inventory of 1970s to 1990s era reinforced concrete bridges on Delhi ring roads, NHAI national highways in Uttar Pradesh, and DUSIB and PWD maintained flyovers in Delhi NCR as part of periodic bridge maintenance treatments (typically at 10 to 15 year maintenance cycles) to prevent or retard the carbonation progression that leads to costly structural rehabilitation works; the large surface areas of bridge substructure (pier and abutment surfaces) are economic targets for anti-carbonation coating because the cost per square metre of protective coating is very low compared to the concrete repair and rehabilitation cost it prevents

Key Advantages

• EN 1504-2 compliant CO2 barrier with documented SD value for engineering performance specification — MC-Dur 1000 compliance with EN 1504-2 (Surface Protection Systems for Concrete Structures) includes independent laboratory measurement of the CO2 diffusion resistance SD value per EN 1062-6 — the key performance parameter for anti-carbonation coatings defined in EN 1504-2 as equivalent air layer thickness (SD value in metres) — and classification as Class I (SD value greater than 50 metres), Class II (SD value greater than 200 metres), or Class III (SD value greater than 1,000 metres); MC-Dur 1000 at the specified application DFT is classified and documented with a measured SD value that can be incorporated into the engineering specification with a verifiable acceptance criterion — enabling the structural engineer or building owner to specify MC-Dur 1000 with a measured, documentable CO2 barrier performance rather than a generic description
• Single-component formulation for direct application by roller, brush, or spray without two-component ratio mixing — MC-Dur 1000 as a single-component product (requiring only dilution with clean water at the specified percentage for the first primer coat, and applied directly for subsequent full-strength coats) eliminates the two-component mixing ratio management required by the MC-Dur Elastic elastomeric coating, making it more practical and reliable for large-area anti-carbonation coating application by standard painting contractor teams on building facades, parking structures, and bridge surfaces where application consistency over large areas is the key quality parameter