Glass fibre reinforced concrete or GFRC is a type of fibre-reinforced concrete. These are mainly used in exterior building façade panels and as architectural precast concrete.
Somewhat similar materials are fibre cement siding and cement boards. They consist of high-strength, alkali-resistant glass fibre embedded in a concrete matrix.
In this form, both fibres and matrix retain their physical and chemical identities, while offering a synergistic combination of properties that cannot be achieved with either of the components acting alone.
Also, keep in mind that the fibre can be of different types in GFRC.
Let’s get into each of them now.
Constituent Materials of GFRC
There are mainly 5 constituent materials of GFRC. They are,
- Ordinary Portland cement 53 grade was used for the experimental program.
- It was tested for its physical properties in accordance with IS standards.
2. Fine Aggregates
- The fine aggregates used for experimental program was obtained from the bed of the river.
- The fine aggregates used passed through 4.75mm sieve and had a specific gravity of 2.68. The fine aggregates belonged to Zone II according to IS 383. 2
3. Coarse Aggregates
- The coarse aggregates used were non-reactive and as per the requirements to produce good and durable concrete.
- It’s of two different gradings and as such a definite mix proportion was used to obtain the desired grading for coarse aggregates.
- One grade has a maximum size of 12.5mm and a minimum 10mm. And for the other, the maximum size was 20mm and minimum 12.5mm.
- This combination was used for casting cubes, cylinders and prisms. This is done to avoid the bailing effect of concrete mix
Ordinary tap water which is safe and potable for drinking and washing was used for producing the concrete
5. Glass Fibers
- Glass fibre, also known as fibreglass is made from extremely fine fibres of glass.
- It is a lightweight, extremely strong and robust materials. Glass fibre, the most popular of the synthetics, are chemically inert, hydrophobic, and lightweight.
- They are produced as continuous cylindrical monofilaments that can be chopped to specified lengths or cut as films and tapes and formed into fine fibrils of rectangular cross-section
- Used at a rate of at least 0.1 per cent by volume of concrete, glass fibre reduces plastic shrinkage cracking and subsidence cracking over steel reinforcement.
So, we dug deep into inside of Glass fibre reinforced concrete. Next, let me walk you through the advantages of GFRC.
Glass Fibre Reinforced Concrete Advantages
The main advantages are,
1. Low weight and high strength
- Self-weight of structures decreases when GRC is used and demands on foundations are reduced.
- GRC cladding is suitable even for very high-rise buildings and offers good performance under seismic loading.
2. Freedom of shape
- GRC is easily moldable into a wide range of shapes, including intricate grilles, panels with a double curvature and 3-D objects.
- The high freedom of shape permits the production of structurally very efficient elements.
- Easily cast, it can produce items with very fine details and reproduce very complex features and elements of both modern and historic buildings.
- Basic reinforcement is non-ferrous and the GRC products are not susceptible to corrosion as in traditional reinforced concrete.
- Low permeability and a very slow rate of carbonation offer protection against corrosion of steel in adjacent reinforced concrete.
- GFRC has an inherently high resistance to extreme exposure conditions (freeze/thaw, fire etc.)
- An extremely wide range of attractive surface finishes is available.
- It satisfies the highest requirements for an aesthetic appearance of new structures and capable of matching colour and texture of surfaces of existing buildings.
- Durable and brightly coloured surfaces with enhanced self-cleaning can be achieved in a variety of textures and shapes.
- The relatively low weight of GRC products reduces CO2 emissions associated with their transport.
- There are no Volatile_organic_compounds or other pollutants emitted from the material itself, neither in production nor in use.
- GRC is fully recyclable into concrete and other applications.
- In addition, the photocatalytic E-GRC reduces directly and significantly the concentration of pollutants in the surrounding air, leading to a better quality of the environment.
- This is good especially in congested urban centres and at a minimal additional cost.
Now, how about a quick glance through the applications?
Applications of GFRC
Due to its versatility the range of GFRC is growing.
- All the categories of buildings have been constructed using GFRC
- Small, simple and unsophisticated items for everyday use are made using GFRC in a large-scale
- Architects prefer GFRC to fulfil high structural complexity, size of construction elements, freedom of shape to achieve spectacular appearance, durability and the highest quality
- Positive environmental performance
That’s it. Time to sum up.
- GFRC has a large scope of application and research and development is going on
- It is a very versatile material and the freedom of shape makes it the number one choice by architects
- Glass fibre reinforced concrete is used from small scale household products to large scale buildings of structural complexity
So, how is our buddy GFRC? Let me know your thoughts in the comments.
Also read: Shotcrete – An overview| Shotcrete vs Gunite