JANUARY 27, 2021
Shipping containers are a cost-effective and efficient option for building robust structures. While shipping container homes, offices, and storage units have become popular alternatives to traditional construction, people are also increasingly looking into buried container solutions for underground systems. However, buried shipping container construction differs significantly from its aboveground counterpart.
If you're planning on building an underground bunker or a storm shelter, read on below. We’re looking into how to bury shipping containers for underground applications.
A shipping container bunker should serve as a safe haven. You do not want your container to fail or the walls to collapse due to intense ground pressure. If you're using an adequately reinforced shipping container, you’ve already eliminated most of the risks surrounding a structural failure.
Still, there are some additional factors that you should consider while using a shipping container bunker underground to ensure adequate safety.
Most safety issues generally arise from not buying the correct shipping container. If you purchase your container from a reliable supplier, you will most likely receive a structure that's safe from these hazards.
Shipping containers with appropriate safety measures, reinforcement, and ventilation can be incredibly safe as underground bunkers. Now, let’s take a look at how to make shipping containers ready-to-use for underground purposes.
A shipping container has a monocoque structure, which means the corner frames carry most of the load while the walls are comparatively weaker. When you bury a shipping container underground, the ground pressure from all sides can be intense. Some underground bunkers have about six feet of soil layer over them.
Even if the walls do not fail completely, cracks and dents can be detrimental to the structural integrity of your shipping container bunker. Therefore, every underground container requires appropriate reinforcement to improve its strength.
So, how much strength does your container need? Think of a heavy truck or trailer moving along the surface above the ground. In that case, you’ll need to ensure the bunk doesn’t cave from the additional pressure created by the vehicle above. Below are some of the best ways to reinforce buried containers.
If you bury a shipping container correctly, you can help prevent any setbacks from occurring later on. Remember, an underground shelter that does not come in direct contact with neighboring soil will not cave in due to the pressure. Here are some steps you must follow while burying cargo containers for underground use:
A gabion cage is a simple yet robust solution for adding reinforcements around your container walls. Build a steel cage in the space surrounding your underground bunker and fill it with stones to create a barrier between the soil and the container.
Modifying the shipping container's structure with additional support members is the most effective method of reinforcing shipping containers.
Weld strong steel bars along the roof and the periphery of the container. You can use I-beams or strong square tubes as reinforcements. The welded supports will increase the load-bearing capacity of the container and ensure that it won't cave in easily.
You can line up multiple barrels along the edges of the container to ensure that it does not come in contact with the surrounding soil. You could also use sandbags to build a wall around your bunker. While finding used plastic barrels and rock is cheaper than building a gabion cage, they do not offer as much strength as other methods. If there's considerable human or vehicular activity over your bunker, we recommend you stick to other alternatives.
In addition to issues related to container strength, other challenges may crop up when burying your unit. For instance, a Corten steel container may rust rapidly when surrounded by soil that contains high levels of saline. In this case, a protective layer of paint may help prevent corrosion though it may not suffice. Advanced systems and pipelines use cathodic protection to avoid rusting.
A shipping container root cellar must also have uniform walls. Any cracks or dents may compromise the insulation and circulation of the inside air, leading to humidity build-up and mold growth.
Contaminated air may lead to suffocation or health issues, as well. If you bury your shipping container in an area with a lot of dirt or pollution, you’ll need to install an air filtration or circulation system. You must also invest in an effective strategy for managing human waste and greywater. Accumulation of wastewater may lead to bacterial growth, foul odor, and health hazards.
Here are some ways to tackle these challenges:
Now that you know how to transform cargo containers into efficient underground buildings, let’s look at the ways you can use a container buried underground.
People bury shipping containers for different reasons. While some may do so to secure more storage to stash valuables, others may be looking for a safe space from natural disasters. A shipping container will typically last about fifteen years for either application.
Listed below are a few more ways you can utilize a buried shipping container:
Note that you may have to modify the structure slightly depending upon your application. For instance, if you want an EMP-proof container, you'll need to build a Faraday cage.
Using underground shipping containers comes with its own set of pros and cons. Let's look at both the benefits and the challenges they pose.
You can buy a used container at a fraction of the cost of a concrete structure. Their modular build allows you to easily make all kinds of modifications. Since cargo containers are highly portable, you can get a unit delivered directly to the site where you intend to bury them.
You cannot use a container underground without making modifications. Burying a shipping container in as-is condition will cause the roof and walls to cave in. Therefore, you'll need a good amount of reinforcement.Adding a ventilation system, new flooring, insulation, and framing can also be time-consuming, tedious, and expensive.
There are multiple examples of people who failed to ensure adequate reinforcement and had their container walls collapse within days.
A well-built container bunker underground can function as a storm shelter, survival bunker, and storage unit. However, an inefficient design will fail quickly, leading to loss of property, and may even pose a threat to your health and life. Consult with a container modification expert before you finalize the design of your underground container structure.
See also: How to Reinforce a Shipping Container for Underground Use
Complete Guide to Shipping Container Campers
Shipping containers are an excellent choice for all kinds of structures. However, when you bury a shipping container, you must make adequate changes to ensure that your underground unit is safe for use. You must also install appropriate auxiliary systems for ventilation and waste management. Well-designed modifications and safety precautions can help you enjoy a comfortable stay in your underground unit.
Mobile Modular Portable Storage is one of the leading suppliers of top-notch shipping containers. We provide container units in multiple sizes with optional customizations for residential, commercial, and industrial applications. Call us at 866-459-7600 or get in touch with us to learn more about our industry-specific container solutions for rent and sale.
Although you can bury shipping containers underground, you must modify the structure or create a protective wall around the container to ensure it bears the weight of the surrounding soil layer.
It is not safe to bury a shipping container without adding support members to its design. Shipping containers have a monocoque construction. That means the corner frames carry most of the weight, while the walls are comparatively weaker.
As an underground container faces intense ground pressure from all sides, the walls may cave in. While burying a shipping container, ensure that you add robust reinforcements for safely using the structure.
You can weld strong steel bars at the roof and the walls of the container to ensure that they don't shift in due to ground pressure. Alternatively, you can build a protective fence using a Gabion cage, rock-filled barrels, or sandbags to prevent direct contact between the container and the nearby soil layer.
Enter your email address to subscribe to the blog and receive notification of new posts by email.