Concrete Repairing products from Sika

Defects and Sika solutions in brief:

Symptom	Cause	Sika solution
Cracks on horizontal surfaces, as conctrete stiffens	Plastic shrinkage: rapid drying of surface	sealing by brushing with: cement slurry with Sika Latex Or, Sika Top 121 by notch trowel.
Cracks above form, reinforcement of crack in thick sections	plastic settlement or restrained thermal contraction.	cement slurry grouting with Intraplast EP/Intraplast N200/Intraplast NN -expanding grout admixture or, Injection grouting with low viscosity epoxy resin system Sikadur 52/Sikadur 53 depending on the crack dimension. Surface sealing to be done with Sika Top 122 or Sikadur 31 .
Blowholes in formed faces of concrete or voids in concrete, honeycombing	Air or water trapped against formwork, Unsuitable mix design, Unsuitable mix design, Unsuitable release agent or, Inadequate compaction & mortar loss.	For blowholes & honeycombed surface: Sika Latex mortar or Sika Top 122 or Sikadur Epoxy repair mortar system. For voids in concrete: Cement slurry grouting with Intraplast or grouting with low/medium viscosity Sikadur Epoxy Injection system.
Erosion of vertical surface,in vertical streaky pattern	Scouring:water moving upwards against form face.	Cohesive concrete mix with Plastiments or Sikaments water reducers at a low W/C. Additional Sika Pump  is recomended for leaner mixes as pumping aid, viscosiy enhancer & surface improve. For scouring, the above given patch repairing systems may be adopted.
Plucked surface	Insufficient release agent or careless removal of formwork.	Opt for any of the described repair motor system.
Lack of cover to reinforcement	Reinforcement moved during placing of concrete, or badly fixed. Inadquate tolerance in detalling.	Sika Top mortar systems or Sika Latex Mortar for patch repair and two coats of Icosit Elastic I an acrylic dispersion as additional protective coating. Icosit K25 (I/3) -A Micaceous Iron Oxide rich epoxy coating is also recomended as an alternate protctive system.
Cracks in under water structures, Scouring on spillway and bucket section of dams and also in glacies and it's side wall in diversion tunnels.	Earthquake, alkali-aggregate reaction, very high rate of silt flow along with abrasive particles for want of silting basins or impact of bolders.	For cracks: Primary sealing with Epoxy sealing system- Sikagard 694 F(I) and injection grouting wih either Sikadur 53(UF) or Sikadur 53(FLV) injection resin sysem depending on crack dimension. For scouring: Steel fibre reinforced concreting with Sikament range of high range water reducers, Sikacrete densified Silica fume. Sikadur moisture insensitive epoxy lining system is recommended on the areas where the damage is severe.
Corrosion of steel reinforcement in a high temperature-high humidity environment	Aggressive chemical atack on the concrete	Removal of damaged concrete and adherent rust on exposed reinforcements. protective coating Sika Top Armatec110 Epocem/Sika TopArmatec 108 to be applied on the affected reinforcements. The damaged concreteshould be replaced by Sikacem-133 Gunite and the surface should be coated with Sikagard high performance coating to protect the surface from future aggressive chemicals.
Damaged concrete with exposed reinforcements	Fire	Removal of affected burnt concrete and protective treatment for the reinforcements with Sika Top Armatec110 Epocem Spot welding of reinforcements at places should be done if required. Replace damaged concrete by Sika Grout 318 micro concrete or spray concrete with Sikacem133 Gunite. Sika Top 122 is also recomended for patch repair.
Spalling of concrete	De-passivation of the concrete due to carbonation resulting severe corrosion of the reinforcement.	Chipping the weak concrete up to the depth of affected reinforcement followed by thorough cleaning operation and surface preparation  prior to application of Sika Top Armatec protecive system. Patch repairing with Sika Top mortar system.