Grasscrete – Types, Advantages & Installation Process
What exactly is Grasscrete?
Grasscrete is an environmentally beneficial solution that provides us with impermeable pavement for purposes such as parking, water management, and access to emergency vehicles. Concrete is poured over styrene void formers to create grasscrete in a straightforward method. As a result, it is a cast-on-site cellular reinforced concrete system with former-created voids. The basic concept of the former is a piece of machinery or a mould that creates holes in the concrete, which may then be filled with a variety of porous materials like stone, gravel, or plants.
In other words, Grasscrete is a cast-on-site, cellular-reinforced concrete system with voids made by plastic formers. It has a specific design of hollow spaces created with the aid of disposable forms, which, when removed and replaced with grassed soil or stone, allow water to seep through the concrete. As a result, the previous character of Grasscrete is not obtained by the use of any chemical admixtures, but rather through the use of a preset mechanical system, to produce voids in a systematic, regular manner.
The monolithic reinforced ready-mixed concrete pour is made using single-use moulds. The spaces are opened when the concrete has dried out and are then either filled with crushed stone or with plants.
Without sacrificing its attractiveness, the pavement construction can be used all year long. Because it uses a lot of recycled materials, it is a sustainable product. Hence, it provides many advantages over plastic paving systems and precast concrete.
Types of Grasscrete
1. Partially Concealed Concrete:
The vegetation is positioned parallel to partially covered concrete. Besides the plant, there is five-and-a-half-inch thick concrete with a half-inch root barrier.
For locations with heavy traffic, partially disguised grasscrete works well. Also, it is practical, environmentally friendly, and aesthetically pleasant due to the vegetation’s presence.
Partially Concealed Concrete applications include:
- Fire and emergency access
- Vehicle parking
- Access roads
- Road Shoulders
2. Stone Filled Grasscrete:
In grasscrete with stone filling, the soil between the concrete is swapped out for crushed stone. The maximum thickness of the crushed stone is 1/2 inch or 34 inches. Grasscrete with stone filling has a 100% water retention rate and can drain at up to 480 inches per hour.
If you want a very low-maintenance design, this kind of grasscrete is perfect. For places with heavy traffic, grasscrete with stone fill works well. Moreover, it offers the highest rates of percolation. It is useful and environmentally friendly.
Stone Filled Grasscrete applications include:
- Vehicle Parking
- Access roads
- Fire and emergency access
- Military Installations
3. Concealed Concrete:
There is a dirt layer 1 inch deep above the concrete in buried grasscrete. Invisible and five and a half inches deep, the concrete is below this layer of earth. Grasscrete of this kind is best suited for locations with less traffic.
Concealed Concrete applications include:
- Fire and emergency access
- Low-traffic access roads
- Overflow vehicle parking
Advantages of Grasscrete
There are several benefits, such as economic, structural, and environmental ones.
A combination of natural grass and reinforced concrete engineering concepts opens up a wide range of advantages and opportunities. Below are some of the main structural advantages of grasscrete:
High load-carrying capacity:
Grasscrete’s strong load-bearing capacity, which works well with saturated sub-base, is one of the material’s key structural advantages. Up to 114000-pound (51858-kg) trucks can be supported with grasscrete. Even after the sub-base’s grasscrete supply has been exhausted, it still supports other applications like a military tank and light-speed rail track access.
Edge Information not Needed:
In contrast to systems like modular pre-cast concrete or plastics, grasscrete does not require edge restrictions or curbs. It melds seamlessly with the nearby finishes, creating a beautiful appearance.
Differential Settlement Is Resistant:
As is common in modular pre-cast or plastic systems, a monolithic concrete slab evenly distributes the weight of the load over a wider surface area, resisting differential settlement. As a result, Grasscrete is thought to be more resistant to differential settlement than the other options.
Yet, once the concrete reaches the desired compressive strength and flexural strength at the same time, it can be sold because Grasscrete’s structural integrity is independent of the vegetation.
Withstanding Freeze Thaw & Protecting Slope:
Grasscrete’s special pocket profiles enable it to discharge hydrostatic pressure as well as frost heave. This special advantage of Grasscrete aids in difficult slope protection projects.
Compared to other traditional impermeable pavement solutions, grasscrete has a longer lifecycle. In actuality, Grasscrete has installations that date all the way back to 1974 and are still operational today.
Minimises expensive infrastructure:
Grasscrete’s ability to permit natural water infiltration is one of its special qualities. Additionally, it is known that treating stormwater is not only not a workable solution, but is also subject to regulation by many organisations. Hence, the requirement for pricey stormwater infrastructure, such as curbs, gutters, and underground piping, can be diminished or even eliminated in some circumstances.
Low Expenses of Maintenance:
The stone-filled Grasscrete is the most practical choice with minimum maintenance costs. It also has the most use of Grasscrete. Although these gaps are very easy to clean up, clogging of the voids in places with slopes less than 1% is not typical.
There is no need for heavy maintenance like vacuum trucks or planned maintenance. When it comes to vegetation, it can be handled similarly to how other grasslands are handled. Moreover, snow ploughing is simple on grasscrete.
Boosts Green Space and Diminishes Heat Island Effect:
The built-up areas that are hotter than the neighbouring rural areas are known as heat islands. The visually beautiful green space and flora diminish the heat island effect, resulting in a relaxing, pleasant, and comfortable parking area for vehicles. This is how Grasscrete enables the transformation of a desolate parking lot into a lush urban haven.
Utilizes recycled resources:
Grasscrete actively promotes the use of recycled materials from the start of the concrete mix’s production to fill in gaps and subbase layers. Grasscrete keeps its environmental focus by making full use of recycled resources.
In addition to preserving the groundwater recharge’s natural equilibrium, grasscrete greatly lowers runoff. Stormwater infiltration rates in Grasscrete are comparable to those of any other typical lawn in the vicinity.
Moreover, through bio-retention, this infiltration encourages the improvement of water quality. Via plant and soil structure, the metals and poisons are naturally cleansed during this process.
Installation of Grasscrete:
Installation of Grasscrete includes the following steps:
The first step in preparation is to ensure that your workspace is equipped with an edge framework and a sturdy sub-basis. The Grasscrete building schedule is straightforward and uncomplicated. An MOT Type-1 sub-base is laid after the topsoil is removed and the level is decreased through excavation. The sub-foundation is covered with a sharp sand blind, and formwork is constructed for the edge. Make sure there is a binding layer of sand between 10 and 20 mm thick.
600 mm x 600 mm formers should be laid out edge to edge. To fit the space, the formers can be chopped appropriately. Now, the Grasscrete plastic formers are positioned next to one another, leaving a 100 mm space at the joints and the edge.
Formers should be reinforced with mesh. Set the mesh on the up-spacers that are situated between the former’s primary upstand. Separate mesh purchases are required. The formers feature spacers that are integrally moulded to support the mesh reinforcement.
Staging boards are used to help pour concrete into the formers for Grasscrete. Take note of the usage of concrete that flows. Ensure sure the concrete is poured around the mesh and formers and is level with the formers. The concrete is levelled off to the top of the formers using squeegees. The concrete is towelled and let 48 hours to solidify.
Melt Former Tops with Flame Guns:
With the use of LPG flame guns, plastic former tops are burned out, melting the tops of the formers. To give the flame a leading edge, it is suggested that each previous top be punctured with a lengthy steel pipe.
Topsoil and seed:
Fine tribal topsoil fills the crevices in the grasscrete, which is subsequently watered to provide habitation. The planting needs to be watered every day for two weeks after the initial settlement to establish grass cover. Thereafter, until the grass is fully grown, it must be watered as needed.
Grasscrete is a cutting-edge invention that is also socially acceptable. In circumstances where concrete, tar, or other materials might be utilised, it offers all practical solutions while also soothing the urban environment.
Today, Grasscrete allows architects, engineers, and town planners all around the world a new way to work with a surface material that has the strength of reinforced concrete and the aesthetic appeal of grass. New uses for Grasscrete are consistently being found because of its adaptability. Grassblock, Grasskerb, and Grassroad are other alternatives to grasscrete.