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56 APPLICATION & CONSTRUCTION AAC WORLDWIDE %u2022 2.2026APPLICATION & CONSTRUCTIONOvercoming issues related to cracking in wallsSteel mesh masonry bed joint reinforcementLike concrete, masonry has a high compressive strength but a limited tensile strength. This may lead to cracking when tensile and/or shear stresses develop. This phenomenon is more prominent in AAC block masonry. By providing reinforcement to resist such stresses, the chance of cracking is substantially reduced.Cracks in masonry appear due to a variety of causes. The code of practice for construction of AAC block masonry (BIS %u2013 6041 %u2013 1985) states various reasons, including:%u2022 Shrinkage due to drying and movement of blocks due to external influences.%u2022 Movement due to fluctuating temperatures.%u2022 Flexural or tensile stresses resulting from loading.%u2022 Stress concentrations around openings, in the masonry course immediately below the beam.%u2022 Movement of partition walls due to the deflection of the supporting structure.%u2022 Long term creep effects.Murfor Compact (MC) is a steel mesh masonry reinforcement (SMMR) product manufactured by the company Bekaert, Belgium. Since 2016, MC has been in use in various countries in Asia, Europe, and recently also in India. AAC block masonry can be reinforced with steel mesh reinforcement, using general principles like those associated with reinforced concrete.MC SMMR is a convenient, purpose-made reinforcement for masonry for use in the horizontal bed joints. It limits the risk of cracking and increases the tensile and flexural strength of masonry. The unique structure and user-friendly size of this type of reinforcement optimize the construction process and the use of materials.MC has been evaluated by competent international agencies like EOTA for use as a masonry joint reinforcement product complying with various international building codes like IRC, IBC CBC, and FBC. MC is also CE labelled and EPD verified.In India CSIR %u2013 CBRI recently has completed a detailed structural assessment of Murfor Compact bed joint reinforcement through full-scale testing and design evaluation. CBRI has recommended its use as an alternative to the conventional RCC band system.MC SMMR is used as bed joint reinforcement in AAC block masonry. It is made from high tensile strength steel that has been galvanised to protect it from corrosion. A minimum of 15 mm cover to the surface of the block is recommended to increase the protection for the steel. SMMR have been used in many projects for many years in Asia and Europe, and have been preforming as expected in the respective applications.MC SMMR enhances the structural performance of AAC walls by increasing the tensile capacity of the masonry, which significantly increases the in plane and out of plane capacities of the masonry structure.Depending on width, MC SMMR consists of a series of 7 to 14 longitudinal steel wires with polypropylene yarn longitudinally affixed to each wire. The longitudinal wires and yarns are held together with fibreglass cross fibres at predetermined spacings.Er. Rajdeep Chowdhury, Business Head %u2013 VAP & TPO, Biltech Building Elements Ltd., India