What is the correct amount of sand needed to weigh down cardboard boxes?
I run a large non-profit walk-a-thon where we distribute hundreds of cardboard trash receptacles (40 gallon – 18×18 x 30”)over the long route. The problem is that on a windy year, lots of them will fall over. I’m trying to determine how I would figure out how much sand (100 lb/cf) would be necessary to hold down the boxes. The reason is that I need to do this on the large scale and saving money is a premium. Any ideas on how to mathematically figure this out?
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7 Answers
Honestly, this question would best be answered by the trash can provider. The provider/seller should be able to instruct you as to how much weight is needed.
In our village, our trash service provides our trash receptacle free for any parades or other doings. On windy days, they usually just place them next to a tree where they can. Ours have heavier cardboard lids which help prevent tipping or blowing.
Why not redesign the containers to be short and squat, instead of tall and narrow? “Short and squat” won’t blow over as easily.
Speaking of trees, how about duct tape + trees?
Use a neighboring rock or two at the bottom.
Or fill them, with trash.
In addition to the duct tape, as stated above, you can also nail them with one nail to a tree (or something else woody).
They won’t blow over and are easy to take off again.
how much sand (100 lb/cf) would be necessary to hold down the boxes.
How fast is the wind blowing?
From what angle relative to the flat surface of the box (directly = 0 degrees) is the wind blowing?
The amount of sand required will be a function of the wind speed and the weight of the box and the direction from which the wind is blowing relative to any flat surface of the box.
The box will “tip over” once the lateral force (wind) exceeds the downward force (weight of the box) at the center of gravity.
Upon further research the wind speed on that day last year maxed out at 23mph (10 m/s).
Wouldn’t the greatest force be at 0 degrees?
Is the way to do this by determining the wind speed in pascals then convert this to PSI. Next, multiply that number by the area of one side of the box and then make sure that the weight in the box exceeds that number?
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