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This Sandcastle Is So Strong It Can Hold Up An Entire Car On Its Top. Here’s How

sandcastle holding car

Sandcastles, fun as they are, are blown away very easily. Whenever I make one, I admire it probably more than Vauban after making Versailles, but I do know not to trust the strength of the sand castle with the weight of the spade with which I dig the hole as it cannot hold that on its own. But, what you don’t know is that sand and dirt for that matter are incredibly durable materials and if made to stick together. They are weak because of lack of friction between the layers, and if that can be increased, we are looking at a much stronger structure. Here is the video on how a properly made sand castle can hold an entire car on its top:

So, water can be added to the sand to make it stronger and more compact. What it makes it stronger is that it makes the granules of the material stick together and avoid sliding off so that the usual volcano like pile can be avoided. Water adds tensional forces that act perpendicularly to the shearing planes and thus, resist the sliding of the granules that decrease the strength of the material. If you are a civil engineer or one in the making, you would know how engineers use it to their advantage by rolling down granular materials and build seawalls and retaining walls. It avoids the use of cement or concrete which is very expensive on large tracts of land.

So, this trick is based on the same principle. A few thin sheets of material and you are pretty much ready to go. As it can hold a car on its own, we can say that a sufficiently large amount of tensile force will be required to even damage this strong structure.