Topic 18- FRP Composites - Gaby

What are FRP composites?

Composites made of two or more materials

What roles do the matrix and reinforcement serve in composites?

The matrix binds the materials together, while reinforcement provides strength.

What types of reinforcement can be used in FRP composites?

Reinforcement can be particles or fibers, and can be random or aligned.

Are polymers natural or synthetic

Can be both

What is a Fiber Reinforced Polymer (FRP)?

A polymer matrix (typically synthetic) reinforced with materials like glass, carbon, or metal.

What is the polymer matrix in asphalt concrete?

The asphalt binder serves as the polymer matrix.

What is the reinforcement for Asphalt

Aggregate particles

What is the primary use of Fiber-Reinforced Polymer (FRP)?

To wrap damaged structural elements and as a substitute for steel-reinforcing bars in concrete.

And to wrap structural elements in seismic regions

What is CFRP?

Carbon Fiber Reinforced Polymer, made from carbon fibers and epoxy.

What is GFRP?

Glass Fiber Reinforced Polymer, made from E-glass fibers and vinyl ester.

What is AFRP?

Aramid Fiber Reinforced Polymer, made from aramid fibers and polyesters.

What is a thermoset polymer?

A polymer that cures through a chemical reaction, typically involving a monomer and an activator.

How are thermoset polymers cured

With UV, Temperature, or air

What are the characteristics of carbon fibers in FRP composites?

Carbon fibers have high tensile strength and modulus of elasticity but are stiffer and more brittle than steel.

What are the common forms of FRP?

Structural shapes like rods, bars, and planks/strips.

What is the benefit of using dry fabrics in FRP composites?

They are flexible, easy to install, and can fit geometries with limited access.

What is the purpose of flexural strengthening in FRP composites?

To enhance the load-bearing capacity of beams by aligning fibers parallel to the beam.

How is FRP used in column confinement?

FRP is wrapped around columns to increase their compressive strength.

What is the process for repairing fire-damaged concrete using FRP?

Remove damaged material (cover), prepare the surface, and use shotcrete with steel wire mesh for bonding.

What is a friable material

material that crumbles under a light load (typically after damage)

Why is epoxy injected into damaged concrete

to seal internal cracks before shotcreting

What is the function of rubber bridge bearings?

To resist compressive and shear forces from the bridge's weight and thermal expansion.

What are rubber bridge bearings comprised of

layers of rubber and steel

What is the purpose of base isolation bearings?

To reduce shaking of a building during an earthquake.

What maintenance is required for rubber bridge bearings?

They require lubrication and corrosion protection to maintain functionality.

What are the main components of Composites

Matrix and Reinforcement