What is shotcrete? Shotcrete has been around for over 100 years. Shotcrete not only saves money and time, but it also produces better-quality concrete!
Shotcrete is the perfect solution for a variety of construction needs, such as building roads and houses in remote areas, repairing dam spillways, and building man-made tunnels.
If you’re looking for a cost-effective material, shotcrete is the answer. It has all the advantages of concrete with added benefits. Read on to learn more!
What is Shotcrete?
Shotcrete is a type of concrete that is sprayed onto a surface, as opposed to being poured. Shotcrete can be used in construction for many purposes, such as to fill gaps and holes, seal cracks, and create a smooth surface.
Shotcrete is typically made of portland cement, water, and aggregates such as sand and gravel. The concrete is applied at a high velocity, which allows it to form a strong bond with whatever it is applied to.
Shotcrete can be applied by using a shape gun, which is an air-powered device with a nozzle on the end. It is also applied by using a concrete applicator machine.
If a construction project calls for complex shapes such as curves or other unique forms, shotcrete is an excellent choice. It can be applied quickly and does not need as much formwork beforehand.
Shotcrete is commonly used to build smooth rounded shapes, such as swimming pools and skateboard parks. It is also commonly used to repair existing concrete, as the high-speed application bonds the new concrete to the old effectively.
Retaining walls and similar concrete construction projects also benefit from shotcrete, as the applicator can get into tighter spaces faster and more effectively.
Benefits of Shotcrete
There are several benefits of shotcrete. Shotcrete typically has lower labor costs than other types of construction because less skilled labor is needed to apply it to walls and roofs. Shotcrete also has lower material costs than brickwork, since less brick and mortar are needed for the same amount of wall height.
Shotcrete application is also extremely fast. This can save immensely on labor costs. It is also beneficial in situations where a quick application is necessary, such as building water retaining structures.
Contractors can use shotcrete for extremely thin applications, which is useful for more artistic installations. It is also easy to apply overhead, which makes it a popular choice for water-retaining installations.
The use of shotcrete has increased dramatically over the last few decades because it is a more cost-effective way of building than traditional methods such as bricklaying or traditional concrete forms with steel reinforcements.
What is the Difference Between Shotcrete and Gunite?
All shotcrete is made from a base of portland cement. However, there are two main ways that it is applied.
The first is a wet-dry mixture. The dry shotcrete mix moves through an applicator gun via air pressure. The water is added at the very end of the line, as the shotcrete exits the gun nozzle. Wet-dry shotcrete is also known as Gunite.
The more common type is a wet mixture, which is referred to as “shotcrete”. An operator mixes the cement slurry in a specially designed machine. This machine then pumps the wet concrete mixture through a nozzle.
How to Prepare Shotcrete for Use
To prepare shotcrete for use, you need to mix the ingredients accordingly and then apply them to the surface you plan on using it on. There are many different ratios that you can use for mixing, but the most common one is a 1:3 cement-to-water ratio, with a few other ingredients mixed in depending on the situation.
The ratio will depend on the type of shotcrete you are using. For example, if you are using fast-setting shotcrete then you will need about two parts sand and one part cement for every 10 liters of water.
Additional ingredients may include things like:
- An accelerator, which speeds up the curing process
- Bonding agents that allow for stronger adhesion
- Water reducers that quickly evaporate any water on the application site
- Superplasticizers reduce the amount of water needed in the shotcrete
- Stabilizers that strengthen the shotcrete mixture
When applying shotcrete, the first layer is applied thick enough to cover the entire surface and should cure for at least 24 hours before applying another layer. The last layer is applied with less thickness so that it cures more quickly, in order to avoid cracking and curling when it dries out completely.
Curing Process for Shotcrete
The shotcrete curing process can take up to 72 hours. This time period depends on the thickness and the temperature of the concrete.
Shotcrete curing time depends on the curing agent used. The most common agent is water, which needs at least 4 hours to reach its full strength. Calcium chloride solution or magnesium chloride solution need 12 hours before they are strong enough to be walked on.
The shotcrete curing process can be broken down into three stages: wet-curing, air-curing, and hardening. Wet-curing takes place when the concrete is sprayed onto the surface. This stage can last up to 24 hours, depending on the type of curing agent used.
Air-curing takes place when the wet concrete dries and hardens in the open air. This stage lasts anywhere from 2 days to 3 weeks, depending on temperature and humidity levels.
Hardening occurs over time after air-curing has finished. This process takes anywhere from a few months to years before it reaches its full strength and hardness level.
Basic Tools Needed for Shotcrete
Many of the tools and supplies used for applying shotcrete are also used in regular concrete construction. However, shotcrete itself requires some sort of application machine.
Some types of machines used by shotcrete contractors include combination mixer-pumps, gunning machines, dosing pumps, and mixing machines. Shotcrete contractors also need tools such as trowels, floats, and vapor barriers.
Professional Shotcrete Contractors
The answer to “what is shotcrete” is simple: it is the most cost- and time-effective way to build with concrete in the world! Its ease of use, wide range of applications, and savings make it a no-brainer for any concrete construction project.
If you’re looking for professional shotcrete contractors, we have almost 70 years of experience and are one of the biggest names in shotcrete construction. We offer a wide array of shotcrete services.
Our knowledgeable shotcrete experts are waiting to help you with your next concrete project. Contact us online or call us at (818) 896-9199 to get started today!