Containment Wall – Know Everything in this Complete Guide!
Have you been looking over a retaining wall and made it this far? Do you have a lot of doubts about this important construction of civil engineering? Or is it just a curious one who arrived at this text alone?
Either way, you are in the right place! Because we will deal with the subject of the retaining wall, types, drains and even a few more things.
Are we all ready?
Continue without precaution!
What is a retaining wall?
The retaining wall, also called the retaining wall, is a wall that holds a large pile of earth.
However … It’s not just that!
The main function of the retaining wall is to actually hold the weight of the earth that is next to the construction site, but its function is also to stabilize the pressure and containment of the soil, thus decreasing the risk of collapse, preventing it from sagging.
It is common to see it on the roads of BR, where, in regions with many mountains, the retaining walls prevent the earth from sagging on the roads, thus preventing various types of accidents.
Therefore, the retaining wall is a great option for land that has a slope or slope, but has been cut to become flat. Once the cut is finished, there will be the accommodation areas, the space between the original profile of the lot and the area that has become flat.
Containment walls prevent slipping
Before and after a landslide
As previously said, the retaining wall is of great importance for the safety of people.
Just to better illustrate the importance of the retaining wall. In some countries around the world, such as Japan, the retaining wall is widely used to prevent landslides in mountainous regions, which unfortunately is a recurring phenomenon in that country, especially during the time of taifus (typhoons) or in strong earthquakes.
It is noticed that this type of system needs to be well planned, calculated and executed to prevent fatalities or subsequent disasters, especially during rain, since the land tends to become heavier when wet.
Stages of a retaining wall project
There are two steps to creating a retaining wall project, which are:
Choosing the dimensions of the wall
A skilled designer can, through experience or even empirical formulas, choose the dimensions required for the wall. The walls can have rectangular, trapezoidal, staggered faces.
Checking the stability of active efforts
If the forces acting on the structures, such as the weight of the element itself, the thrust of the earth, eventual loads applied to the top of the wall and soil reactions are properly determined, it is possible to have an idea of the stability of the work.
Types of retaining wall
The retaining walls are divided into two categories, both of which have processes peculiar to each other. These categories are the gravity retaining wall and the bending retaining wall.
Gravity retaining wall (or weight)
A type of gravity wall, the gabion
As the name implies, this type of wall uses the weight of the material itself to contain the soil, using gravity to its advantage. It is used to contain small or medium unevenness, less than 5 meters. The most well-known types of walls are:
Although it is the type of wall most used in the past, nowadays its use has been neglected due to the high cost and the difficulty of finding or sculpting stones of regular dimensions. Luckily, we now have other types of methods and materials that are more viable.
However, such disadvantages do not mean that this method is all bad. After all, it is a very simple process and still does not require drainage – since the stones arranged by hand do all the work of draining water, on their own.
It is recommended that the stone masonry wall is used for retaining heights of up to a maximum of 2 meters. Because this technique has risks of rupture due to landslides, it is advisable that the base of the wall has a minimum width of 1 meter or half a meter, in addition to needing to be supported on a level below the level of the terrain. From that point on, it is necessary to use cement and sand mortar to fill the voids in the stones. However, if you adopt the filling of the voids in the stones, you will have to implement drainage elements, such as sand drain or geosynthetic drain and pipes.
From a more ecological option, we go to the most controversial – controversial if they do not follow the environmental restrictions that exist in certain Brazilian states – the soil tire retaining wall! This wall is a viable and inexpensive option, in addition to not requiring specialized labor. HOWEVER, for efficient and flawless work, it is necessary to follow a guidance manual made by specialized agencies. This technique can be used on slopes or buildings.
These walls are built by launching horizontal layers of tires, by which they are tied together using a rope and filled with compacted earth. Thanks to its weight, the tire wall cannot exceed the height of 5 meters, and its base must be 40 to 60% of the height of the wall.
Soil-cement bag wall
“That it? Trenches of the First World War? ”
No! Although they look like those bags used in the trenches of the First World War, the bags of the soil-cement sack wall have a totally different function and composition from that bloody time in our history.
In this method, raffia, polypropylene or burlap bags are used, usually closed with thin string. Unlike the trenches of the First World War, it is not filled with sand, but a mixture of soil with cement and a little water. Then, they are positioned to form rows (layers) which are then punched, covered by another layer, and so on until the wall is fully erected.
This method is recommended on sandy soils with a risk of severe erosion, with a maximum height of 4 to 5 meters.
Cyclopean concrete wall
Calm down, it has nothing to do with cyclops (unfortunately). For more information on cyclopean concrete, we have this text dedicated just for that.
Anyway, what would this cyclopean concrete wall be?
It is a structure composed by filling a form with blocks of rocks of different sizes and concrete. It is a very economical wall for heights less than 4 meters. Drainage is done with geosynthetic blankets and tubes that direct the water at the back of the wall.
The use of a cyclopean concrete wall is generally recommended for low-structure works.
Also known as a cage wall or a campfire wall. Crib-wall walls are structures made up of precast concrete, wood or metal elements. They are connected longitudinally and the internal space is filled with coarse granular material, in addition, they are able to accommodate small settlements of the foundations.
A notable advantage of this type of wall is that it does not require any maintenance, the only exception being the elimination of large vegetation that can displace the structure. Its use is recommended in the containment of embankments and embankments.
The gabion walls are a kind of cages filled with stones arranged by hand. The cages are secured by galvanized steel wires in hexagonal mesh with a double twist, and can even be coated by double galvanization or by a PVC layer.
It is a very resistant and flexible wall, allowing the structure to accommodate settlements and permeability. The most common sizes of this type of wall are 2 meters long and a cross section of 1 meter edge. This type of wall can be used on highways and embankments near streams.
Bending retaining wall
The bending dumbbells are visually more dazzling than the weight walls and have an L-shaped cross section. This format, strange as it may be, has a reason for being so, since the “L” shape at the base allows the wall to have balance.
Although they use not only the weight of the material itself to support the load of the earth as the main means of containing the soil, they also use resistant materials and armed with steel bars. In the matter of supporting the strength of the soil, the concrete plus steel set is made, in other words, they are reinforced concrete walls.
The most popular types of bending retaining wall are:
Reinforced concrete wall
The most common and used bending wall, the reinforced concrete wall, is composed only of concrete and steel. Its use ranges from containing the earth to serving as a base for grounding and leveling the land. Its components are the foundation shoe and the wall that contains the soil.
Armed block wall
It is a wall widely used to replace the wall in conventional reinforced concrete, with structural blocks filled with reinforced concrete.
Wall with buttress
A great wall for large structures. Along its length, there are the so-called “buttresses”, which are nothing more, concrete walls built perpendicular to the wall. The reason for the existence of the buttress is to guarantee the rigidity of the structure.
Wall with beams and pillars
An interesting form of construction of retaining walls is the use of a wall with beams, pillars and filled with blocks. In this type of wall, it is important to build good foundations for the pillars.
BONUS CURIOSITY: Bamboo retaining wall!
Concrete? Stones? Cement? No, bamboo! Widely used to contain low slopes, even reaching higher heights if it is built in a staggered way, it is a cheaper and more sustainable option in situations where traditional materials of civil construction are not available.
To build the bamboo wall, it must be placed horizontally and fixed at the ends with small wooden pillars (piraletes) supported on the ground, forming a kind of panel. The bamboo wall must be made in planes, thus forming a kind of “corner” so that it offers greater stability.
Although it seems like a very fragile alternative, it does its job well, as long as there are no pandas around…
A warning never hurts
First of all, especially in the age of the internet where anyone has access to information, it is never bad to make a warning: always look for a trained and trained professional to build a retaining wall.
Never try to build a retaining wall or any type of civil construction work without the help or leadership of a trained professional. As you can see, it is a construction of extreme importance for the protection of people’s lives, if done poorly, it can lead to disasters and countless fatalities.
Therefore, even though some of the materials cited below appear to be easy to construct manually, never try to do it yourself. It can cause consequences without turning back.
Rain on the earth is like destructive mud
One of the biggest causes of the collapse or landslide of declining terrain is undeniably rain.
That is why, if the retaining walls were created, their main function is to prevent the soil from sagging and destroying everything that was underneath, holding the earth with everything it can. However, if you do not take proper care, the combination of water plus earth (mud) can overcome the retaining wall. For this reason, a good rain drainage proper to the wall is practically law.
A very important care is with the calculation of its structure, since it must include the additional load provided by the water, as a safety margin. Obviously, the calculation must be done before the construction of the retaining wall.
The rain drainage system can be made by means of barbacans, small PVC pipes installed along the wall. Another drainage option would be the creation of a layer of draining material between the soil and the wall, where the water is directed to a perforated pipe that drains the water, not forgetting to place gravel between the earth and the drains, to avoid clogging.
Although the solution above does not work on 100% of the walls, since in all situations or types of walls it asks for different solutions, what really matters here is not to fail to perform an adequate drainage.
What’s up? Any doubts about the retaining wall answered? If so, wonderful! But know that you were not the only one who was unaware of this important work. So share it with those who want to know more! An extra knowledge does not hurt anyone.