Exposed Aggregate Concrete Driveways
Exposed Aggregate Concrete Driveways are made from one of the most versatile construction material available. Researchers and scientists from all around the world have been studying and experimenting to make concrete a better and more sustainable material.
The Durability of Concrete
Its durability and ease of construction make concrete a first choice for designers and constructors alike in an array of projects. The construction of exposed aggregate concrete driveways is no different. Gone are the days when the driveways were only bituminous, i.e., flexible, which required a very good base to transfer the loads to the soil. Concrete driveways and pavements are rigid, which use the slab action to transfer the loads and therefore work fine even if the base has flaws.
With time, concrete driveways have evolved to exposed aggregate concrete driveways, which are now pretty standard in a number of countries due to the benefits they provide. Exposed aggregate concrete driveways and/or pavements are, simply speaking, concrete pavements having aggregates exposed on the top layer. This brings a beautiful yet rugged feeling to the pavement along with the required friction that a driveway needs.
A plethora of research studies suggest that exposed aggregate concrete driveways offer better skid resistance with less traffic noise (What Is Exposed Aggregate? Exposed Aggregate Concrete Explained, n.d.; Zhang et al., 2014). Although there are multiple other reasons to choose an exposed aggregate concrete driveway over the conventional ones, the two mentioned above set this kind of driveway apart because it deals with noise pollution and provides more safety than its counterparts. Not only has it been used in driveways at private properties, but also on highways all around the world. Some countries, like Australia and the UK, have even gone as far as creating highways and studying their benefits over years long research projects.
Figure 2 Skid Marks (What You Should Do When Tire Skid Marks Appear in Your Street, n.d.)
7 reasons to choose an exposed aggregate concrete driveway over a conventional concrete driveway.
- Skid Resistance – a safer choice.
- Less Vehicular Noise—environmentally sustainable.
- Reduced Glaring
- Versatile – can be produced in different colours with different aggregate textures
- Durable – it is as durable as conventional concrete and can last for around four decades
- Cost Effective - Although a little more expensive than conventional concrete, it offers a cost effective package considering the benefits it brings along with it.
- Ease of construction - It is easier to construct as compared to other options which offer an aesthetic value to the driveway.
As noted above, exposed aggregate concrete offers a more aesthetic yet safer alternative to a conventional concrete driveway. It brings in the option of multiple textures and colours that one can get with the usage of different kinds of aggregates to be exposed on the top layer. Further, variation in colour can be achieved using pigmented cement to create a contrast between the construction and the driveway.
Exposed Aggregate Concrete, although first utilised in the 1990s in Australia and the UK, is still a recent trend for many residences and in commercial landscaping.
Q: How is an exposed aggregate concrete driveway constructed.
Different exposed aggregate concrete installers will have slightly different construction techniques. Technically speaking, there are four methods to achieve an exposed aggregate concrete finish for your driveway.
- Brushing and Washing: The oldest yet simplest method. After some time, the surface of concrete is washed and brushed using a broom to a desirable depth where the aggregates are exposed.
- Using Chemicals: Chemicals – retarders to be specific – are sprayed on the top surface, which slows the setting and hardening time of the upper layer, which later becomes easy to remove.
- Seeding the decorative aggregate: This is rather easy and provides the finishing of one’s own choice. Right after placing the concrete, one can seed the decorative aggregate on the top layer.
- Topping: This method is used when an existing conventional concrete is upgraded to an exposed aggregate concrete driveway. A small layer of exposed aggregate concrete is poured over the already existing slab.
- Mixing the decorative aggregate: Mixing the aggregate to be exposed in the concrete would be an expensive but less labour intensive task.
Q: Is exposed aggregate concrete expensive?
Yes, but not by a huge percentage. Decorative aggregates are usually required in this case, which costs a little higher than conventional aggregate. So, too, is the case with retarding agents – if used!
Q: Is exposed aggregate concrete strong?
Exposed Aggregate Concrete is as strong as conventional concrete. It is no different than conventional concrete except for its surface. It can take vehicular loads just as well as conventional concrete, even during extreme weather conditions.
Q: Should you seal exposed aggregate concrete driveway?
Yes, the exposed aggregate concrete driveway – very similar to a conventional concrete driveway – requires sealing every 4 to 5 years.
Related Concrete Information from Red's Landscaping Melbourne
7 Reasons to Choose Concrete Pavement
4 types of Eco-Friendly Concrete
3 Best Types of Concrete Retaining Wall
9 Concrete facts for Melbourne Landscapers.
3 Best Concrete Path Construction Techniques
7 Great Reasons to choose Permeable Concrete
Landscape Designers Top 9 Tips
© Red’s Landscaping Melbourne - Quality Landscapers Melbourne
References
5 Incredible Advantages of Having Exposed Aggregate Concrete in Your Home - TechSling Weblog. (n.d.). Retrieved October 16, 2021, from https://www.techsling.com/5-incredible-advantages-exposed-aggregate-concrete-home/
Exposed Aggregate Concrete - Decorative Pebble Finish - Concrete Network. (n.d.). Retrieved October 15, 2021, from https://www.concretenetwork.com/concrete/exposedaggregate/
Nakhi, A. Ben, & Alhumoud, J. M. (2019). Effects of Recycled Aggregate on Concrete Mix and Exposure to Chloride.
Perth’s Best Exposed Aggregate Driveways - Decorative Concrete WA. (n.d.). Retrieved October 15, 2021, from https://www.decorativeconcretewa.com.au/exposed-aggregate/
Understanding the Meaning of Exposed Aggregate Concrete. (n.d.). Retrieved October 16, 2021, from http://www.cedarlinecontracting.ca/understanding-meaning-exposed-aggregate-concrete/
What Is Exposed Aggregate? Exposed Aggregate Concrete Explained. (n.d.). Retrieved October 15, 2021, from https://www.absolutescapes.com.au/faq/what-is-exposed-aggregate/
What You Should Do When Tyre Skid Marks Appear in Your Street. (n.d.). Retrieved October 16, 2021, from https://www.staineaters.com.au/burnout-mark-removal/
Zhang, J. P., Liu, G. Q., & Wang, P. Z. (2014). Skid-Resistance and Noise-Reducing Characteristics of Exposed-Aggregate Cement Concrete Pavement. Advanced Materials Research, 1052, 352–357. https://doi.org/10.4028/WWW.SCIENTIFIC.NET/AMR.1052.352
