CFRP strengthening

Carbon FRP reinforcement methods mainly include CFRP strengthening and CFRP strip reinforcement.CFRP strip is a composite material pultruded with carbon fiber fabirc and resin, adhering to the characteristics of carbon fiber, light weight, high strength, and corrosion resistance.

Key feature of CFRP strip

- High strength

- High modulus

- Lightweight

- Non-corrosive

- Unlimited lengths

- Minimal preparation of laminates

- Easy to install

- Outstanding fatigue resistance

- Alkali resistant

Where to use CFRP strip

Load Increase:

- Increased live loads;

- Increased traffic volumes on bridges;

- Installation of heavy machinery in industrial building;

- Vibrating structures;

- Changes of building utilization

Damage to Structural Parts:

- Aging of construction materials;

- Vehicle impact;

- Fire;

- Blast impact

Change in Structural Parts:

- Removing of wall or columns;

- Removal of slab section for openings

Design or Construction Defects:

- Insufficient reinforcements;

- Insufficient structural depth

Technology principal

A pultruded carbon fiber reinforced polymer (CFRP) laminate designed for strengthening concrete, timber and masonry structures. 

The resin for carbon fiber strip is affixed to the surface of the component to form a new composite body, and it bears the bearing capacity and seismic resistance together with the original component to increase the strength and rigidity of the structure.

Technical process and key points

Preparation for construction → Surface treatment → Preparation of impregnated resin → Bonding carbon fiber laminate → Fixing carbon fiber laminate → Surface protection

1, Construction preparation

Formulate construction plan, prepare tools and materials

2,Surface treatment

1) Concrete matrix

Remove oil, dust and other loose aggregates from the surface, repair large irregularities or holes in the surface, make the surface level enough, if necessary, use light blasting, sanding or other conducive bonding methods deal with

2) Steel substrate

Remove surface dust, oils and greases, rust, rust, crushed skin, suggest high-pressure cleaning, grinding or sandblasting;

3) Wood substrate

Remove surface oils and greases, impurities, sand blast or grind it to roughen it.

3，Preparation of impregnated carbon fiber laminate resin

4,Bonding carbon fiber laminate

1) The carbon fiber board should be cut to the size required by the design;

2) The surface of the carbon fiber board should be wiped clean to free of dust. When two layers need to be applied, both sides of the bottom carbon fiber board should be wiped clean;

3) The clean carbon fiber board should be immediately coated with structural adhesive. The adhesive layer should be arched at the center and the average thickness should not be less than 2mm.

4) The carbon fiber board coated with glue should be lightly pressed by hand in the position to be pasted. Use rubber roller to smooth evenly along the fiber direction to make the glue squeeze out from both sides to ensure no void. When parallelly sticking multiple carbon fiber plates, the gap between the two plates should not be less than 5mm.

5) When two layers of carbon fiber sheets need to be applied, paste them continuously. When it is not possible to paste immediately, clean the underlying carbon fiber sheet before resuming the bonding.

5,Fixing carbon fiber laminate

1) Remove the excess glue from the surrounding area, fix it with steel frame, press it properly, and squeeze out micro glue around.

2) If there is a gap or a lack of glue, fill it with glue.

6,Surface protection

If the reinforcing member needs fire protection, it can be coated with refractory coating after resin curing.