Drop Test
Drop Test
(OP)
Drop Test of a rectangular Box
I want to do a drop test analysis of a Steel box with inside full of concrete. And planning to drop from a height of 1 meter. Falling towards the covering plate cornor. The dimensions are mention below.
I would like to know Is there any Hand calculation to find the stress produced in the box.
Dimension of Outter box : 400 x 400 x 400 x 10 mm
Inner box : 380 x 380 mm
Box covering Plate : 400 x 400 x 400 x 10 mm
Surface : 800 mm x 800 mm
Can any one sort this issue calculating stress by hand calculation. For drop test.
I want to do a drop test analysis of a Steel box with inside full of concrete. And planning to drop from a height of 1 meter. Falling towards the covering plate cornor. The dimensions are mention below.
I would like to know Is there any Hand calculation to find the stress produced in the box.
Dimension of Outter box : 400 x 400 x 400 x 10 mm
Inner box : 380 x 380 mm
Box covering Plate : 400 x 400 x 400 x 10 mm
Surface : 800 mm x 800 mm
Can any one sort this issue calculating stress by hand calculation. For drop test.





RE: Drop Test
Tobalcane
"If you avoid failure, you also avoid success."
"Luck is where preparation meets opportunity"
RE: Drop Test
if it's hitting the "surface", how thick and how supported ? these affect the resiliance of the surface, and so the duration of the impact, etc, etc ...
then, of course, where on the surface ? and what orientation of the "box" ? point (corner) first ?
RE: Drop Test
The outter box is made of steel.
Inside that steel box concrete is added.
As I mentioned it ll b 10 mm thick walled box.
Duration can be found out by knowing the height of drop and "g".
The tip ll b hitting the ground first as the centroid and the tip will be constrained to have 90 deg. with the ground.
Thanks
RE: Drop Test
That's not what he was asking. That's the duration of the drop, not the impact. You need to have some idea of how long it takes from the instant the corner of the box touches the table to when it stops touching the table.
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RE: Drop Test
Corner? Flat bottom? Edge? Unknown?
What is your limit on the (de)acceleration of the contents of the box: OBVIOUSLY - I don't care if a box containing concrete falls on the floor - unless somebody is underneath it, or unless the floor is going is going to break.
RE: Drop Test
I just want to check whether my stress results of Abaqus are correct or not.I am getting around 350 Mpa. the total weight of box including inside box is 236 kg.
Can anyone tell whether this figures are correct or not.
As this cross check is for just to validate my results.
Thank you
Ali
RE: Drop Test
Fe
RE: Drop Test
RE: Drop Test
When the floor compresses the bottom steel - as you point out, but ONLY if it hits the floor perfectly flat - the top of the tank and its internal concrete will continue "down" as the impact shock wave slams up. Then that impact wave will hit the top of the tank, and will then rebound and try to force the upper concrete inside "out" spreading the walls, and the lower part of the concrete "out" at the bottom. Since the weight of concrete increases from top to bottom, the lower corners are going to get stressed most.
The concrete is not cement "dust" and has a modest amount of tension strength. (It will be able to crack though under impact, and the very fact that it is concrete means that it has no "give" and transmits shocks "perfectly" and fits the steel walls "perfectly" tight with no air ghaps.) But I expect the failures to occur at the lower corners. Example, fill a square paper lunch bag with sand and drop it. The failure will not be the bottom of the bag itself, but the lower corners and sides of the bag.
If the bag were filled with a more compressible load like loose soil, then the rebound loads are smaller since there is more room for the soil to compress rather than squish outwards.
RE: Drop Test
Tobalcane
"If you avoid failure, you also avoid success."
"Luck is where preparation meets opportunity"
RE: Drop Test
RE: Drop Test
If this is anything more than a classroom/training exercise .. build it, fill it, wait for the concrete to dry, then drop it.
RE: Drop Test
Tobalcane
"If you avoid failure, you also avoid success."
"Luck is where preparation meets opportunity"
RE: Drop Test
RE: Drop Test
Tobalcane
"If you avoid failure, you also avoid success."
"Luck is where preparation meets opportunity"
RE: Drop Test
RE: Drop Test
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