What is G.R.C

Glass fiber Reinforced Concrete (GRC) is a cement-based composite Material reinforced with alkali-resistant fibers. The fibers add flexural, tensile and impact strength and the resulting Material allows the production of strong yet lightweight products used in architectural, civil engineering and many other applications.

  • Light weight in comparison with due to small thickness.
  • Design flexibility, rapid forming, smooth surface, multi colors.
  • Water absorption not exceeds .01 % after 28 days immersion.
  • High binding strength (20 n / mm2), high impact strength (21N / MM2).
  • Compressive strength (60N / mm2), shear strength (10N / mm2).
  • Non combustible, thermal conductivity (0.9 – 1.5 w / M C).
  • Sound isolation (T. Loss G R C thick 15mm = 35 db at 500 Hz).
  • Glass fiber = 4 – 5 % by weight
  • Shell thickness = 15 : 20 mm nominal
  • Dry Density = 2000 Kg/m3
  • Ultimate Bending Strength (MOR) = 20 MPa
  • Ultimate Tensile Strength (UTS) = 8 MPa
  • In-plan Shear Strength = 8 MPa
  • Compressive strength (ASTM D695) = 60 MPa
  • Modulus of Elasticity = 1370 MPa
  • Outside Corner Radius = 1.5 to 3 mm
  • Impact (ASTM D256) = 15 KJ/m2
  • Fire Protection Resistance: BS 476 Part 4
  • 1 – Alkali-resistant glass fiber (4: 5%):Glass fiber shall be an alkali-resistant continuous filament fiber developed and formulated to have high strength retention in hydraulic cement environments.(ARG FIBER AR 2500 H).2– Portland cement (40%):Cement shall be supplied by a manufacturer of assessed capability made to recognized standards and supported by suitable certification cement shall be correctly stored and kept dry to avoid deterioration.3– Sand (40%):Washed and dried silica or another acceptable material successfully used in GRC production.

    4– Water (13%):

    Water shall be clean and free from deleterious matter.

    5- Admixtures (2:3%):

    Admixtures are permitted and their use is encouraged as they can enhance the properties of GRC .they should always be used strictly in accordance with the suppliers’ recommendations and the producer must ensure that their use has no adverse effect on the product. (We use SikaLatex or Sikament).

FABRICATION

Construct of rigid materials that will result in finished product conforming to profiles dimensions and tolerances indicated. Use form release agent compatible with architectural finish and joint sealants.
Carefully measure amounts of mix constituents to achieve desired mix proportions. The consistency of the mix should be tested by measuring the slump. Combine cement, glass fiber, sand, and selected admixtures in proper proportions to meet design requirements provide glass fiber 4: 5 %.
1- Spray mist coat consisting of matrix without fibers onto forms, this coat should be as thin as practicable (1:2 mm) and should be followed immediately by the first GRC spray.2- Proceed with spraying up main body before mist coat has set using procedures that produce a uniform thickness and distribution of glass fibers and matrix.3- Consolidate applied materials by rolling or use another technique to achieve complete encapsulation of fibers and compaction. The GRC materials must be sprayed and built up in thin layers of 3-4 mm until the required thickness is achieved.
4- Control thickness by using a pin gauge and compared to the design thickness.

A- Anchor Bolts.B- Steel Shapes, Plates, Bars.C- Stainless Steel.

D- Galvanized Steel.

E- Steel channels and angles.

F- Galvanized Self-drill screw.

A- Exterior tape and bed joints are to be attached with an exterior grade construction adhesive. Then taped and floated using fiberglass mesh tape and a bedding compound of Portland cement, bonding agent, water and fine washed silica sand and clean the joint to match piece surface and shape.

B- Countersunk fasteners and damage are to be patched using same bedding compound as used to float joints.

C- Control joints or exposed joints to be filled with appropriate backer rod and

A sealant capable of withstanding ±0.25% joint movement between G.R.C. panels.

We can also use Epoxy and Polyurethane Elastomeric material

(Such as Sikadur and Sikaflex-1a)

1- Spray mist coat consisting of matrix without fibers onto forms, this coat should be as thin as practicable (1:2 mm) and should be followed immediately by the first GRC spray.2- Proceed with spraying up main body before mist coat has set using procedures that produce a uniform thickness and distribution of glass fibers and matrix.3- Consolidate applied materials by rolling or use another technique to achieve complete encapsulation of fibers and compaction. The GRC materials must be sprayed and built up in thin layers of 3-4 mm until the required thickness is achieved.
4- Control thickness by using a pin gauge and compared to the design thickness.