N Harris,
If you have access to a welder or someone who can weld for you I have found that pouring concrete footings at the 4 corners with a thick metal plate (eg. 1/2" x 8" x 8") embedded in the top of the concrete footing makes a great attachment. You weld the square casting blocks on the corners of the shipping container to the metal plate embedded in the concrete footers. Your idea of chain or other scrap metal can also be implemented by welding those items to the bottom of the embed plate such that the concrete and steel all form a massive anchor on each corner of the container. Your idea of an auger hole is also ideal in my opinion as it gets your anchor deep into the soil.
Be sure that your anchor points are square to each other in the orientation you plan to place the container and also verify that all 4 embed plates are level with one another before concrete is mixed and poured. Most container casting blocks are close to 6" square so sizing your metal embed plate larger than that size will give you some leeway if your measurements are off slightly.
Depending upon what will go inside the container you may choose to place an additional set of footings on each side of the container at the midpoint (20 ft). Containers are designed to handle large amounts of weight supported only by their four corner casting blocks, so you can decide if your application needs the mid-span support.
With weld plates welded on two sides at all four corners your container will be significantly more "attached" to the earth than you could get with chains or rebars driven through the casting blocks.
Good luck on your
project.
Kevin
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James,
Mobile home anchors would work, but if the container needs to be placed on the ground it is very difficult to make those systems applicable without some working room between the item being anchored and the ground surface.
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Jon,
Dirt berming can be done with containers, but be advised that the sidewalls and roofs of containers are neither designed nor built for an application where pressure from dirt cover will be applied continuously. I have built with containers on rocky hillsides where the sidewall and end walls are backfilled up 2/3 of the wall, but I added additional support metal to make sure the sidewall could resist the constant push from the earth. What I used was metal cut out of the side walls of other containers to double and triple the thickness of the metal. This also had the added benefit of placing other metal between my container wall and moisture. If something does have to get sacrificed to rust, it will be one of the other layers before my container wall.
I would never attempt to bury one in dirt subject to flooding or standing
water either. The result would be the same as a septic tank that was not filled with water before a big rain -- it could float out of the hole.
Your thoughts on waterproofing are also spot on if the walls will be covered.