Carbon Fibre Reinforced Polymer (CFRP) has become one of the most widely used materials in structural strengthening. Lightweight, high-strength, and corrosion-resistant, CFRP allows engineers to enhance load capacity without significantly increasing structural weight or altering the building’s geometry.

However, not all CFRP are the same. Choosing the right type depends entirely on the structural purpose and condition, load demand, and project objective. To choose the right type, proper structural assessment is needed to determine the cause of damage, the concrete condition and to calculate the load capacity.

The Main Types of CFRP Systems

1. CFRP Sheets (Wet Layup)

This is one of the most common strengthening methods. Carbon fibre sheets are saturated with resin and applied directly onto concrete surfaces. It is ideal for:

• Flexural strengthening of beams and slabs
• Shear strengthening of beams and columns
• Confinement wrapping of columns

Advantages include flexibility around irregular surfaces and suitability for confined areas. However, surface preparation is critical, and installation quality directly affects performance.

2. CFRP Laminates (Pre-cured Plates or Strips)

These are factory-manufactured carbon fibre plates bonded onto concrete using structural adhesive. CFRP Strips are best suited for situations that requires higher tensile strength in a controlled alignment and increasing flexural capacity of beams and slabs.

Laminates offer consistent quality and higher strength efficiency but require flatter surfaces and careful bonding preparation.

3. CFRP Rods or Near-Surface Mounted (NSM)

In this method, grooves are cut into concrete cover and CFRP Rods are inserted and bonded with epoxy. CFRP Rods are used for:

• Strengthening where surface bonding is limited
• Improving flexural capacity with better anchorage
• Situations requiring enhanced durability

NSM often provide better protection and anchorage performance compared to externally bonded sheets.