Column Strengthening
- Remove entire Plaster from the column surface carefully by chipping with Chipper machine.
- A light tapping on the column concrete surface to carry out to check the damage and honeycomb concrete area etc.
- Damage area to remove carefully with a chipper machine.
- The entire concrete surface is clean off any loose particles, dust, oil residues etc.
- Repair damage and chipped off areas are using polymer mortar. Any undulations, pin holes present on the surface is filled up with the site made polymer & cement putty.
- All the corners/edges to round off smooth with the help of grinder
Application of Laminate Adhesive and Laminates
- Laminate adhesive, Master Brace 4000, components A & B will be mixed in the prescribed proportion (0.57: 0.43 respectively) mechanically as per the manufacturer’s specification until a homogenous uniform colored mix is obtained.
- One layer of laminate adhesive, around 3-5 mm thick are prepare to a concrete surface as well as on the one side of the laminate.cut Laminate to require length and keep ready.
- Master Brace Laminate having 100 mm width to fixed on the concrete surface and using the hard roller, constant pressure to exerted by moving the roller in the direction of laminate or along the length of the laminate. Hold the Laminate in that position for a while till it sticks to adhesive properly. To do this use jack prop in the center and at the end.
- Apply a prescribed number of laminates are on the column surface at a distance.
- Remove the props after laminates have properly adhered to a surface. The same will take a couple of hours depending on the ambient temperature.
Carbon fiber wrapping
Surface Preparation
- After carbon laminates properly adhere to the surface, the gap between two carbon laminates is fill up with site mix polymer cement putty to level the surface. For this, the acrylic polymer of BASF and Cement are mix together to form the putty-like consistency. Using painters’ blade apply putty over the concrete surface to make the concrete surface level with laminates.
- Allow the putty to cure for a day before taking up fiber wrapping work.
Primer Application
- Mix Master Brace 3500 Primer, Part A & B together in prescribed proportion as per technical data sheet using mechanical stirrer.
- The mix material to be apply to the prepare and clean surface.
- The application to carry out using a nylon brush and allow for drying for about 6 to 10 hours before application of saturant.
Saturant and Fibre Application
- Carbon Fiber reinforcement system to cut to required size before application of the saturant.
- Mix epoxy saturant, Master Brace 4500 part A & B thoroughly by a mechanical stirrer to get a uniform colored mix.
- First coat of the fully mix saturant is apply @ 500 gms per coat per sqm area on the concrete surface by Nylon brush.
- Immediately fix pre-cut Master Brace Carbon Fibre over the surface. The orientation of the fibers must be the correct direction. In case of columns, the orientation of fibers must be in the horizontal direction. That is, perpendicular to main vertical reinforcement steel.
- The fiber reinforcement system is strongly squeezing in the longitudinal direction of the fibers two or three times using a deforming roller and rubber spatula in order to impregnate the resin into the fibers and to deform the resin coat.
- Ends of the fiber sheet are extent on the slab bottom surface by 300 mm. Two fiber sheets to be overlap and additional resin to apply at the overlap location on top of the outer layer of fiber sheet to be overlap.
- The adhered fiber reinforcement system to allow to stand for at least 30 minutes. Any lifting or dislocation that occurs during this period to correct using the roller and spatula.
- The second or overcoat of mixed saturant to apply onto the surface of the fiber sheet after the first coat is sufficiently dry.
- The coated surface to strongly squeeze in the fibers in longitudinal direction two or three times with the roller and spatula in order to impregnate the fiber sheet as above.
- While still, the second coat is tacky, quartz sand to sprinkle over the surface to make it rough.
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