Beam Strengthening using Micro concrete Jacketing
- Remove entire plaster to reach parent concrete surface if the beam is plaster.
- Now by tapping with a light hammer, identify of loose concrete portions are present. After identifying and marking, remove loose/bad concrete if any by using breaker machine attached with a suitable chisel.
- The concrete surface sounds will be clean of any loose particles, dust, oil etc. And will make rough with an angle grinder.
- 14 mm Dia. & 75 mm deep holes will be drilled in the beam concrete at 1000 mm c/c in a staggered manner or as per drawing using Bosch drilling machine to fix the shear connectors.
- Holes will be clean using air blower and shear connectors of 10 mm Dia.A 75 mm long HYSD bars to fix using Masterflow 935 or equivalent high-performance resinous fixing and anchoring compound.
Fixing Reinforcement Steel:
- Cut and bend HYSD bars of 12 mm Dia.
- HYSD bars are in position and tack weld/anchor to the existing steel in place.
Fixing of Formwork & Pouring of Micro concrete
- Make shuttering ply and silver wood according to the size of the jacket.
- 100 mm dia hole will be cut using core cutting machine in the slab on the face of the beam to facilitate the pouring of micro concrete.
- Place and fixed a formwork around the beam keeping in mind the required thickness of the jacketing.
- Make formwork joint to be watertight using POP.
- Single component readymade Micro concrete Masteremaco 346 of BASF in 25 kg bag to emptied in a small drum. Two-third of recommended water to the mixed using measuring jar.Mix well for about two minutes using stirrer attached mixing machine. Add fifty% by weight of five mm down cleaned aggregates into the mixed Micro concrete.
- Add one-third of water and mix it for one minute till homogeneous mix obtain.
- Before pouring of Micro concrete make the surface pre-wet by spraying water.
- Pour manually to form-work.
- Remove after 12 to 16 hours / next day and column to covered immediately with hessian cloth and sprinkled with water for curing.
- Curing should carry out for next three days.
People carrying out the surface preparation and jacketing should wear required PPE such as helmets, safety shoes, double harness safety belts, fall arresters, Nose Mask, ear plugs, safety goggles, hand glove rubber/leather/cotton etc.