Reducing Downward Force of 900kg Soil Container

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Discussion Overview

The discussion revolves around methods to reduce the downward force exerted by a soil container weighing approximately 900 kg (2000 pounds). Participants explore various approaches to make it easier to slide open the bottom of the container, considering factors such as pressure, friction, and design modifications.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • Some participants suggest that the downward force is a result of gravity acting on the mass, implying that reducing the soil volume is one way to lessen the force.
  • Others propose increasing the bottom surface area of the container to decrease pressure while maintaining the same soil mass, which would require a shallower container.
  • Several participants discuss the role of friction and suggest methods to reduce it, such as using lubricants, bearings, or changing the design of the sliding mechanism.
  • One participant mentions the idea of using a beam in the middle of the container but does not clarify its purpose, leading to questions about its effectiveness.
  • There are suggestions to tilt the container, use a hinged door, or construct a sloping bottom to facilitate easier opening.
  • Some participants express uncertainty about the setup and the specific mechanics involved in the sliding process, indicating a need for more details.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the best method to reduce the downward force. Multiple competing views and approaches are presented, with some focusing on reducing pressure and others on minimizing friction.

Contextual Notes

Participants highlight limitations in understanding the specific setup of the container and the mechanics of the sliding mechanism, which may affect the proposed solutions.

Who May Find This Useful

Individuals interested in mechanical design, soil mechanics, or those working on projects involving heavy containers and sliding mechanisms may find this discussion relevant.

Calvin5767
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I am making a soil container of size 1meter x 1 meter x 0.60 meter or (3.2feet x 3.2 feet x 1.9 feet)
with soils in it, it weights approx 2000 pounds/900 kg.

I want to know, how can i reduce the downward force of that 900kg.
(the bottom of the container can be slide open, hence i need a lower downward force, so that its lighter to slide)

I found a way to do that by putting a beam on the middle of the container, is there a more effective way?

Thank you geniuses
 
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Welcome to PF;
I am making a soil container of size 1meter x 1 meter x 0.60 meter or (3.2feet x 3.2 feet x 1.9 feet)
with soils in it, it weights approx 2000 pounds/900 kg.

I want to know, how can i reduce the downward force of that 900kg.
You can't.

The force is due to gravity acting on the mass - so you could reduce the soil volume.

What you want it to make it easier for the bottom to slide open.
Assuming contact with the ground is not the problem, but soil pressing from above, you need to reduce the pressure of the soil.

You can do that by:
1. tilting the container so the bottom is no longer horizontal;
2. placing something between the sliding thing and the soil (to reduce the friction);
3. change the sliding whatever with a hinged one - then the weight will help it open;
4. make the slider smaller.
 
you can increase the bottom surface area of container, so the pressure on bottom decrease.
to maintain the constant amount of soil, you can decrease the height of container.
 
Simon Bridge said:
Welcome to PF;

You can't.

The force is due to gravity acting on the mass - so you could reduce the soil volume.

What you want it to make it easier for the bottom to slide open.
Assuming contact with the ground is not the problem, but soil pressing from above, you need to reduce the pressure of the soil.

You can do that by:
1. tilting the container so the bottom is no longer horizontal;
2. placing something between the sliding thing and the soil (to reduce the friction);
3. change the sliding whatever with a hinged one - then the weight will help it open;
4. make the slider smaller.

Thank you for the detailed reply. Is there any way that the pressure will reduce by changing the shape?
 
I have no idea what "putting a beam on the middle of the container" means.
1. A horizontal plate, moving under soil, experiences frictional forces. As Simon says, reducing the coefficient of friction, by lubrication, or say, using a plactic sheet will reduce the force necessary to move the plate. Teflon is expensive but will do the best job here.
2. You would reduce the force if you put a grate above the plate to help support the dirt. Depending on how cohesive the soil is, this may work...but then again will prevent at least some of the soil from falling.
3. Its not clear to me why you failed to describe your set up. How is the bottom plate/floor/panel supported?
Lets say it is only supported by the groove it slides into on the side-walls. There are two possible sources for additional forces: one is our old friend friction - lubricants, and ball (or roller) bearings would reduce that as above. The other possibility is that the weight of the soil is deforming the plate so that it is in contact with the groove (binding). Increasing its rigidity (thickness or supporting 'rafters') would reduce deflection which might be binding it in its groove.
 
But: reduce pressure by increasing the area of the bottom for the same mass - this means shallower soil.

But I suspect your problem is more related to friction.
The door slides along a track of some sort (whatever it is that stops the door just falling out) with soil pressing on the other side?

You can lubricate the track
You can put bearings on the track
You can include a lever or other simple machine to multiply your effort.

A smaller door in the bottom - maybe two half-size doors instead of one big one.
Use a completely different design of door - hinge or iris perhaps.

You can construct a sloping bottom (say, like an inverted pyramid or prism) - put the sliding door in the sloping sides.

You are basically spoiled for choice here - what is the context for this project?
 
Last edited:
Infinite/Zero said:
you can increase the bottom surface area of container, so the pressure on bottom decrease.
to maintain the constant amount of soil, you can decrease the height of container.
My idea is not good as of Simon Bridge's idea.
 

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