Reinforcing of construction

Construction process: 

The process for reinforcing of material by carbon composite needs to be carried out by a high-technical staff, to be methodically trained. Besides, it is necessary to own engineers who deeply know how to construct and reinforce of carbon composite material by supervising and closely instructing. 

Step 1: Scratching of coating mortar layer till concrete layer, grinding and smoothening of concrete surface: 

  • At beam or column angles, they must be chamfered, rounded to the minimum diameter of 2cm, in order to reduce local stress, causing damages of angles and breaking of FRP fiber. 
  • Cracks with width more than 0.25mm need to be glued with epoxy, glass coating before reinforcing. 

Step 2: Cutting of FRP plates relative to designed dimension: 

  • Cutting tools must be provided by FRP manufacturer.
  • Fiber is only cut longitudinally, for minimizing of horizontal cutting, in order not to cut horizontally, causing damage of carbon fiber. 

Step 3: Gluing of carbon compozite: 

 

  • After cleaning of concrete surface, a thin layer of epoxy will be coated on the surface, also layering epoxy on FRP plate, then, FRP fiber is glued on concrete surface. Roller is used to roll evenly according to the direction of fiber, in order for glue to penetrate into FRP plate and not to make the air to remain. Sand is scattered on FRP surface for creating an abrasive layer when it is finished.
Note: As for FRP pieces to be pre-cured, when gluing into concrete surface, which is bordered with wall, a certain gap could be existed between concrete surface and FRP piece, this gap can be sealed by Sikadur 752. 

Step 4: Checking of abrasion for FRP and concrete surface: 

  • After FRP reaching the designed strength (07 days), FRP’s abrasion and concrete surface must be checked by specialized abrasion meters, such as PosiTest AT-A. 
  • In some cases, it is necessary to carry out load test on beam, column, floor to be reinforced with FRP for checking of bearing capacity after reinforcing.