I have a shelf that I want to put a very small aquarium upon. However, I am concerned about how much it can hold.
Is there a way I can safely test how many pounds it can safely handle? Are there methods to test what something can safely carry without breaking it?
Thank you so much for any help you can provide.
It really depends on how the shelf is mounted to your wall. If you're into numbers, you can use the formula:
$$\text{Load Capacity = (Material Strength × Width × Thickness × Thickness) / (8 × Length)}$$
But I suppose material strength values aren't that easily available, and specific shelfs can be more complicated, so you'll have to resort to experimental tests.
An aquarium is a stationary load. If your shelf can hold it for a few seconds without bending, it can hold it for an indefinite period of time (hopefully). So I suggest you just keep the aquarium on top of it and be ready to hold it if the shelf falls. Testing with smaller loads will only prove that the shelf can handle those smaller loads; the behaviour is unpredictable for larger loads as shelf-failure is an abrupt event with no observable signs beforehand.
Better to just go off of your intuition and install additional supports if required.
What kind of brackets are you using? I'll assume inverted 'L' brackets (with optional triangular bracing).
If using multiple brackets - three, for example, each supporting 1/3 of the load - then you can test each bracket at double its expected load and see how it survives.
Note that applying the load close to the wall will give almost 100% shear loading with little pull-out force. Applying the loading at the outermost point on the bracket would result in pull-out force pivoted around the point of contact between the bottom of the bracket and the wall.
Add details you your question and you'll get better answers.
