UNIBOND SBR, a SBR based polymer, helps in strong adhesion of layers of concrete, in new constructions and rehabilitation.
Unibond Sbr CHARACTERISTICS
State : Liquid
Colour : Reddish Blue
Unibond Sbr APPLICATIONS
- In repair of damaged RCC structures.
- In repair of damaged industrial floors and RCC tanks.
- For restoration of old buildings.
- For repair of honeycombed structure
- For bonding of layers of concrete in new construction (construction joints).
- Mixed along with cement grout to stop water leakages.
Unibond Sbr ADVANTAGES
- Provide strong bonding between old & new concrete and helps absorb stresses due to differential expansion and contraction.
- Improves water impermeability.
- Provides high compressive, tensile & flexural strength.
Unibond SBR GUIDELINES FOR USE
Polymer Modified Mortar
- After exposing the reinforcement, it is cleaned manually by wire brush.
- The loose concrete around this area is then chipped away and removed.
- Mix UNIBOND SBR and cement in 1:1 ratio to form a consistent slurry.
- Apply a bond coat using the above slurry with a fine brush to all the exposed concrete.
- While the bond coat is still tacky, apply the UNIBOND SBR polymer mortar in paste or dough form (the ratios and procedure as shown below), build it up layer by layer, with each layer being not more than 15-20 mm at a time.
- After the first layer is applied it is left to dry for 24 hours before the second layer is applied.
- The process is repeated till the old concrete thickness is re-achieved.
Proportions
Cement 5 parts by weight
Quartz / River sand 15 parts by weight (for beams and columns a mix of fine and coarse quartz / river sand in the ratio 40:60, while for slabs the fine to coarse ratio is 60:40)
The above are mixed till a dough-like consistency is reached. Small quantity of water (about 3 - 5% by weight of mortar mixture) may be added to help achieve ideal workability of the dough. A rough test to check the ideal work ability is to drop a fist sized ball made of this dough into the dough mixture from shoulder height. The dough should not shatter on impact.
8. After the polymer mortar has built up the concrete to its original thickness, the treated area is to be kept moist for 4 - 5 days before the final plaster coat is done in the usual manner.
Polymer Cement Grout
- Take 1 kg of UNIBOND SBR, 4 kg of cement and 2 - 3 kg of water (depending on the flow required) (Polymer : Water : Cement = 1 : 2-3 : 4) by weight.
- Mix UNIBOND SBR and water for about 2 minutes.
- Add this solution to the cement and mix till a consistent slurry is formed.
- Grout as recommended.
- Any modification in the proportion may be made in consultation with your RCC consultant or our technical services.