How Gunite Concrete Mixers Are Used to Build Curved Structures



In the construction business, concrete structures are typically made using poured cement. This typically involves the use of other resources such as wooden moulds in which the concrete can be set in the desired shape. While this may be an effective method of concrete construction when creating things like foundations and columns, its limitations are evident when used to construct curved surfaces.


When it comes to the construction of structures such as tunnels, pools, and skate parks, construction workers need to rely on a less arduous and more sophisticated method of tackling the job. This is where gunite comes in; it is an alternative type of concrete dispensed at high speeds through a hose fed by concrete mixers.


Much of what we do here as BS Power has to do with construction, especially construction involving the application of cement and the use of concrete mixers. Nearly every property development project requires the use of cement as one of the primary resources, especially here in South Africa.


Considering this, we thought it canny to inform our readers – and homeowners in general – about gunite. This form of cement can be utilised instead of traditional pouring cement in a myriad of construction projects to create better structures faster and at lower costs.


Gunite is fast becoming one of the most popular methods through which commercial builders are constructing any sort of structure involving contours or curves of any kind. In this article, we are going to take a deep dive into the attributes of gunite that make it so popular.


We are also going to discuss several jobs within the construction industry that rely almost entirely on the use of gunite to complete. We will then discuss gunite’s most popular use: the construction of swimming pools. We will discuss the pros and cons of gunite pools and will also explain how gunite pools are installed.


What Is Gunite?


Gunite is a composite of cement, sand, and water much like regular concrete. The main difference is its method of application. It is a form of concrete that construction workers can apply directly to surfaces using a hose fed by concrete mixers.


Using compressed air, operators of a gunite hose can apply layers of concrete directly to any surface, even vertically. Gunite can even be sprayed to create curves without workers having to go through the painstaking task of creating a mould.




The versatility of gunite’s hose-ejected application allows users to construct contoured shapes with ease and its quick adhesive qualities make it easier to apply concrete in hard-to-reach areas. This makes gunite the popular choice among personnel using concrete mixers to develop structures such as bridges, tunnels, and artificial dams.


What Are More Benefits of Gunite?


First and foremost, the use of gunite in construction as opposed to traditional concrete tends to be the most cost-effective option. And better yet, gunite cementing jobs take substantially less time to complete.


The ductility of gunite is improved through the use of fibres of steel as opposed to the more costly use of wired mesh. This is a more cost-effective method of providing structures made from gunite with a means through which to accommodate for concentrations of local stress.


The high velocity at which gunite is pneumatically discharged from the hose causes what we call compaction; this, along with the substance’s inherent adhesiveness, allows for gunite to be sprayed on both vertical and overhead surfaces with ease.


Additionally, this compacting of the concrete as it is applied over numerous layers strengthens the adhesion of the bonds between the concrete and the surface it is being applied to. This has the added effect of preventing or mitigating the likelihood of shrinkage.


Gunite is also substantially less porous than traditional concrete. This makes it excellent for water storage and the construction of pools. Water cannot seep into the concrete and weaken the bonds between the concrete particles.


The best thing about gunite is the fact that it has solved a critical issue in construction involving cement mixers; many jobs are either incredibly costly or simply impossible to perform using the traditional conventions of poured concrete.


Examples of Useful Gunite Applications


Artificial dams


Gunite can be mixed with a lower water-to-cement ratio to prevent both the porousness and susceptibility to weather damage that make building water storage units out of concrete difficult. Gunite dams can thus enjoy the benefit of the strong compaction that results from the application process, preventing containers from cracking as they would if made with traditional concrete.


Slope stabilisation


Gunite is a popular choice in material for the structural maintenance of made-made slopes such as those seen along mountainous main roads and highways. Its adhesive qualities make the application process much easier on a sheer-faced structure.


Contractors can simply use concrete mixers to feed a gunite hose which can then be used to spray concrete against the surface of a slope, compacting it against the wall as it does so. This allows the gunite to seep into cracks and tears, filling them and providing structural rigidity to any weakened or loose material on the slope.




Mining tunnels require the use of a special form of gunite called blastcrete. The aforementioned compaction of gunite that occurs during application makes the concrete structures it forms less porous this makes gunite more waterproof than any other method of applying concrete fit for mining.


Needless to say, compaction also increases the density of structures, thus making them more durable than traditional poured concrete.


Furthermore, the gunite can fit the shape of any surface it is applied to. This goes for vertical as well as overhead surfaces. Inside mines where tunnels are manually excavated, walls and ceilings tend to be uneven and jagged. Gunite has no issue with adhering with and moulding to fit these surfaces.




Gunite Swimming Pools




Homeowners who are planning on having pools built on their property should consider the use of gunite in the construction. Not only is this the fastest way to construct a concrete basin for a pool, but it can also be the cheapest.


The first phase of a gunite pool project involves the excavation of the earth into the desired shape of the pool. A buttressing framework made of rebar will then be constructed around the boundary of the pool. This will supply the gunite with the support it needs to retain its shape.


Next, concrete mixers will spray gunite over the rebar frame. The gunite will be applied in numerous thick layers, creating a firm and compact surface that will later be manually smoothed out before it begins to set.


For most homeowners, the next step is to decide on an appropriate finish to end off the project. Gunite’s versatility once again lends a hand here because its surface allows for many options in terms of decoration. Using tiles, plaster, or a combination of both, homeowners can design a style and colour scheme to match the aesthetic of their house and surrounding garden.


After the finishing touches are completed, all that is left to do is turn on the taps and brace for a hefty water bill. The end result, however, will be well worth it. You will be left with an excellently designed and structurally reliable swimming pool that your grandkid’s children will one day still be able to enjoy.




However, with great swimming pools come great responsibilities. Depending on environmental factors and usage, pools constructed out of gunite might eventually require homeowners to perform a refinish.


This would entail the application of a new finish to the surface of the pool. This will help to retain a smooth pool surface and keep your pool looking beautiful. Looking on the bright side, many homeowners use refinishing as an opportunity to shake things up and create a fresh new style for their swimming pools.


Another common issue that gunite pool owners may come across is with algae. The aquatic flora tends to thrive in these kinds of pools if left unchecked due to the porousness of the gunite’s façade. Homeowners with gunite pools are thus encouraged to perform filter and chemical maintenance regularly.




These minor drawbacks should not dissuade you from considering the installation of a gunite swimming pool on your property, however. There are several advantages to having a gunite pool. For instance, fiberglass and vinyl pools have serious issues with retaining their shape over long periods of time whereas gunite pools do not warp and thus never lose their shape.


Better yet, gunite pools are known to increase the market value of homes. For shrewd homeowners, this is a clever way to make a pool pay for itself in the long run. If you were to eventually sell your house, your gunite pool will increase the resale value.


Design freedom is one of the best benefits of using gunite to construct a pool. Unlike traditional concrete, gunite can be effortlessly laid into whatever shape you desire. Many around the world have used gunite to create pools that can only be described as artistic marvels, right in their backyard.


When considering the aesthetic benefits of using gunite to construct pools, it should come as no surprise that gunite has fast become the most popular choice of pool installed in most hotels and resorts.


As mentioned prior, the options are sprawling when it comes to applying finishings to your gunite pool. After the cement mixers have shaped the pool, homeowners can choose to decorate their pools with tiles, shells, stainless steel, crystals, and so much more. Pool experts typically recommend the use of plaster due to the compound’s versatility in terms of colour options.


The compacting of gunite onto the host surface without the need for a mould leaves no seems behind, lending much more durability to structures made from gunite. Seems are weak points in traditional poured cement and they are typically where concrete structures begin to form cracks first.




Need Concrete Mixers? Get in Touch


If you require high-quality tools and machines for landscaping or construction jobs, look no further than BS Power. We have one of the largest online catalogues of power tools and heavy-duty equipment here in South Africa. Our products range from everything to do with property construction to an extensive range of landscaping tools.


Regardless of the scale of your project, we are positive that we have the tools necessary for the job. We sell tools fit for commercial applications and are able to support the hardware requirements of whole companies.


We also sell power tools fit for domestic application that homeowners can rely on for years to come. For more information on the cement mixers we retail as well as access to the rest of our catalogue, continue exploring our website.