• Extra reinforced strength due to the presence of fibres
  • Shrinkage compensated
  • Suitable for high build applications
  • Suitable for use in marine and industrial areas
  • Prevents the corrosion of steel reinforcement in concrete
  • Can be applied by trowel, pump or spray
  • High strength repair of concrete

DESCRIPTION : Polyrepair ST50 is a high strength structural polymer modified repair mortar. The product is specially formulated by blending OPC with non shrinking additives, fibers, polymers and fillers for repairing of beams, columns and Slabs in structures which are subjected to dynamic loads and traffic.


Surface preparation : The surface of the concrete to be repaired should be sound, clean and uncontaminated. The decayed or damaged area should be saw cut, keeping the sides of the area as square as possible. Loose materials must be removed carefully using suitable means such as sharp tools or chipping hammer. If the reinforcement is corroded make sure that the back of the steel is completely exposed. Then clean the steel to bright metal condition.


a. Reinforcement steel: After cleaning, prime the reinforcement using Zinc rich primer (Polyzinc*). Brush apply a continuous coat of Polyzinc to the dry steel. A second coat may be applied after 1-2 hours to cover all the pin holes.

b. Concrete: If the concrete damage is severe and is due to chloride attack, a bonding coat with

Polybond EP*/Polybond AC* is advisable before placing Polyrepair ST50 to achieve optimum bond in the fresh and cured sections. To achieve optimum bond between fresh and cured section, Polyrepair ST50 should be applied when the bonding coat is still tacky. For new concrete saturate the area to be repaired thoroughly with water prior to the application of the repair mortar.

Mixing : Polyrepair ST50 can be mixed by mechanical means. Slowly add the Polyrepair ST50 to 3.50- 4.0 ltr. of clean gauged water (W/P ratio of 0.14 – 0.16 approx) working well to produce a smooth mortar. The consistency of the mix can be adjusted by the addition of more powder or water as necessary, depending on the temperature.

Placing and Finishing : Whilst the primer is still tacky, apply the mortar mix and compact well. Application can be done with trowel or a rubber hand glove to paste the material in place. Polyrepair ST50 can be applied to desired thicknesses in layers on vertical and overhead surfaces. High build application can be achieved by using a formwork. While applying multiple layers, the previous layer should be crosshatched and allowed to set before applying the next coat. Polyrepair ST50 can be applied to a thickness of 40 mm in one single application if the ambient temperature s less than 25°C and the weather conditions are normal. Curing Due to the presence of rapid drying polymers, the repaired area shall be cured in accordance with good concrete curing practice by and protected from drying winds. Curing shall be done by non degradable type of curing compounds or wet hessian cloth. When cured with wet hessian cloth, the area shall be covered immediately with a high density polyethyelene sheet which shall be taped to all edges.

CLEANING : Clean all the tools with water immediately after use. Hardened materials can be removed mechanically only.


  • Polyrepair ST50: 13.81L/25 kg (W/P ratio of 0.16)
  • Polyzinc : 7 m2/L Polybond EP : 3-5 m2/L
  • Polybond AC : 4-5 m2/L

STORAGE & SHELF LIFE : Store in a cool, dry place and keep away from all sources of heat and sunlight. In tropical climates, store in air condition rooms. The shelf life is up to 12 months in un-opened condition and if stored as per recommendations. Excessive exposure to sunlight, humidity and UV will result in the deterioration of the quality of the product and reduce its shelf life.

HEALTH & SAFETY : As with all construction chemical products, caution should always be exercised. Protective clothing such as gloves and goggles shall be worn. Treat any splashes to the skin or eyes with fresh water immediately. Should any of the products be accidentally swallowed, do not induce vomiting, but call for medical assistance immediately.