If you work in the building, civil engineering or road construction industries in Australia then we are sure you've heard the term 'ferricrete' floating around. Naturally occurring ferricrete is enjoying a surge in popularity due to its cheap nature and environmental qualities as an alternative to quarried aggregates. But what exactly is ferricrete and why are industries using it? This guide will explain it all.
What Is Ferricrete?
Ferricrete (also known as ferricrust or laterite gravel) is a natural cemented material produced due to cementation of gravel, sand and soil material by natural iron oxide. This natural cementation occurs over thousands of years (mainly in tropical or subtropical areas) with fluctuating water tables where iron rich groundwater exsolves and cements into the profile.
The end result is a heavily textured, dark orange-brown material having a strength and durability to that of concrete, and that's where the name "ferricrete" (meaning "formed by iron", i.e. ferric, from the Latin term for iron ferrum) is derived from. In Australia, ferricrete deposits tend to be found in areas known for weathering and lateritic soils and are widespread in Western Australia, Queensland and the Northern Territory.
Ferricrete is also advantageous by builders and contractors as it occurs naturally and very little work is needed to process it as opposed to manufactured aggregates. It often, ferricrete can be classed as a by the earth and simply crushed to meet the specification before use.
How Is Ferricrete Formed?
Understanding how ferricrete forms can help explain its suitability as a building material. Ferricrete forms by ferruginisation, a process in which Fe oxides and hydroxides are physically transported through the profile (by percolating waters) and precipitated at a specific depth: at or just below the surface. Over extended periods of time the repeated wetting and drying leads to repeated crystallisation of these Fe minerals which cement together the loose sediments to produce a hard crust.
The hardness of ferricrete depends on several factors including the ferric oxide content of the deposit, the nature of the parent material from which the ferricrete forms and the climate at the time of formation. Ferricrete deposits with higher iron content tend to be harder and more resistant to weathering so are used for more hardy applications such as road base and pavement materials.
Key Properties of Ferricrete
Since ferricrete has some physical properties that are desirable for construction purposes, we are going to take a look at these properties.
- Upper false of low compressive strength similar to low grade of concrete or crushed rock
- Very good resistance to weathering and erosion after compaction
- Excellent load-bearing capacity, suitable for sub bases and roads
- Lower permeability, resulting in less water penetration into the pavement layers
- Reddish-brown in colour, stable in colour. Used for ornamentals. Landscaping
- Naturally occurring, less energy to produce than the man-made aggregates
Common Uses of Ferricrete
- Road Construction and Pavement Base
The most common application of ferricrete is in the construction of roads, as a base or sub- base material. The use of ferricrete for this purpose has been traditional because of its natural strength and ease of compaction. It is used by the majority of local councils and civil contractors in remote and urban areas of Australia to provide access tracks, unsealed roads and as a foundation material prior to pavement.
- General Fill and Site Preparation
Made generally of by-products of cement and lime, Ferricrete is usually used as a manufactured fill material for building pads, embankments, and other earthwork situations. It compacts easily and provides a firm and supportive base
- Drainage and Erosion Control
Ferricrete may also be used for drainage works and erosion controls because of its low permeability and its ability to withstand breakdown. It can be used to strengthen embankments, line drainage channels and prevent erosion from surface water in rainy areas.
- Landscaping and Decorative Applications
The red colour of ferricrete is very popular in gardens for drives, paths and mulch for decoration. Gartenscapes use a crushed version of ferricrete to create a natural but durable surface.
- Mining and Industrial Sites
Ferricrete is often specified in such extreme conditions and environment as in the construction of the haul roads and hardstand areas at mine sites. These conditions require a material to be able to stand high wheel loadings and extreme site conditions which ferricrete can do. Locally available sources of ferricrete at many mines assists in reducing transportation and project delivery costs.
Benefits of Using Ferricrete
Cost-Effective Alternative
Due to the fact that ferricrete is a naturally occurring material and that most of the processing takes place within the local quarry and not a processing plant, ferricrete is often a lot cheaper than a manufactured aggregate or imported material. This can also drastically lower the cost of major projects such as roads.
Environmentally Friendly
Using naturally occurring ferricrete reduces the need for manufactured materials such as crushed concrete or processed rock which have a high energy input during the processing stage. If the material is obtained in a sustainable way then this can have a lower carbon impact than material from a quarry.
Durability and Longevity
As is, when compacted, the use of ferricrete results in a durable, hard wearing surface capable of supporting heavy loads, and resisting ongoing weathering.
Local Availability
Ferricrete deposits are accessible within an hour drive of numerous locations in Australia, particularly in regional and remote regions. This minimizes costs in transportation and time where these parameters are deemed more significant.
Versatility Across Projects
Its versatility makes it applicable to a wide range of uses from civil infrastructure to residential landscaping where no specialized equipment or placement and compaction techniques are required.
Things to Consider Before Using Ferricrete
While there are a wide range of advantages to using ferricrete as a site material, it is equally important to get hold of a supplier that can provide assurance of quality and uniformity of their materials. Ferricrete deposits vary in percentage of iron oxide present and, therefore, magnitude of strength and performance, so make sure your experienced transporter and materials supplier can deliver the material either for road base compaction or general fill.
Another point to consider is logistics. When ferricrete has to be supplied in bulk form, the scheduling of transport and handling can be crucial in determining the delivery date, particularly in large civil or mining applications with tight timeframes.
Why Choose Formula Transport for Your Ferricrete Supply Needs?
At Formula Transport we appreciate that the success of any building or civil project depends on access to quality materials when they are required. We can deliver ferricrete for use as a road base, site fill or for drainage works.
Focusing on safety, quality and customer service we work together with contractors, councils and mining companies across Australia, to provide bulk materials into the right place at the right time. Please give the Formula Transport team a call today to discuss your next project and how we can assist with supply and transport of ferricrete.
Conclusion
Ferricrete is a naturally occurring material made up of cemented iron which is the ideal replacement for conventional aggregate in all construction applications. Its strength, low price and environmental benefits make it a highly versatile and attractive product for a multitude of industries from roads and site fill to landscaping and preventing erosion.
Frequently Asked Questions
Is ferricrete the same as concrete?
No. A ferricrete occurs naturally by the binding of iron oxide to soil and gravel; concrete is a mixture of cement, aggregate and water manufactured.
Where is ferricrete found in Australia?
Ferricrete is widespread in the western Australia, Queensland and in the Northern Territory, especially in lateritic climatic terrains of the Tropical weathering provinces.
What is ferricrete used for?
This product is primarily used for road base, general fill, drainage works, erosion control, landscaping and haul roads on mining and industrial sites.
Is ferricrete a sustainable building material?
Yes. Because it occurs naturally and requires very little processing, ferricrete has a smaller carbon footprint than cast products such as crushed concrete.
How strong is ferricrete compared to other materials?
When consolidated, ferricrete exhibits similar load bearing characteristics as low quality concrete or crushed rock.
Why should I use a transport company for ferricrete supply?
A dependable transport provider guarantees a steady supply of uniform quality materials, bulk transport on time, and adequate logistics to support extensive construction and mining projects.
