Surface cracks or joints are opened, cleaned and sealed either with cementitious, acrylic, polysulphide or epoxy sealer The cracks are then fixed with grouting nozzles and masonry elements are generally injected with cementitious grouts and for stone sections epoxy injection grout is preferred. The surface is then filled up with matching shade filler compound.
Cracked monolithic stones columns and masonry elements where ornamental work and aesthetics of structure are to be maintained are stitched together using high strength metallic 6 to 8 mm dia helical ties; depending upon the type of structures, element and system proposed these can be used near the surface as well as in drill holes across the cracks the pieces are hold together using cementitious of epoxy grout. Alternately FRP rods also can be put in place and anchored using epoxy grouts.
A lot of heritage structures use wood as a supporting member, for floor beams, stairs, column sections, etc. these gets deteriorated with time due to moisture, termite or white ant attack and results in loss of structural capacity and may lead to collapse.
Sanrachana provides retrofit solutions for this by using different techniques without compromising on aesthetics. Wherever damaged or cracked the Timber joist can be effectively strengthened in shear as well as flexure by using a composite retrofit system consisting of carbon or glass fiber wraps, laminates in combination with steel rods, grouting and micro concrete recasting. The remaining useable portions are stabilised with anti termite treatment and protective coatings.
Monolith granite beams had encountered a crack along a natural fault line on installation thereby casting doubt on its structural worthiness; Sanrachana with its surface applied CFRP laminate system retrofitted the stone beams thereby restoring its capacity in bending; the system had a very minimal about 4 mm increase in depth of member and didn’t alter the appearance of the beautiful structure. The Surface was then coated with clear epoxy bonded granite crush / dust to restore the appearance.
When it comes to structural performance of masonry, vintage or heritage structures it is far better to be safe than sorry at the first instance itself, so you don’t have to worry about future potential degradation, rickety and unpleasant appearances and related safety risks.
Sanrachana uses newer techniques such as FRP composite and FRCM for improving structural capacity of loadbearing members of older structures which have experienced problems of usual corrosion and deterioration over time. FRP and FRCM systems are long-lasting solution that can be custom fitted to each property; Sanrachana helps in selection, design and implementation of specific retrofit solutions based upon type of structural element and distress issues observed.
Alternately wherever possible or necessary sanrachana also provides load isolation services involving transferring the existing structural load to a newly introduced internal Steel or RCC frame while maintaining the external charm of structure.
Fiber-mesh Reinforced cementitious mortar (FRCM) system involves a specially treated fiber mesh sandwiched in between a special grade high strength cementitious repair mortar.
Sanrachana has trained applicators to apply FRCM layups in layers of about 6 to 8 mm thickness each over damaged masonry surface and when applied as design it is one of the systems that can be used for strengthening of masonry structures and improving ductility for seismic loads.
Masonry columns and load bearing walls are provided with vertical and horizontal bands of FRCM in high strength, light weight and non corrosive carbon fiber mesh to improve its structural Performance; being a cementitious it has a high degree of compatibility with masonry structures.
