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Need help applying 4000 lbs of pressure
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Need help applying 4000 lbs of pressure
For my science fair project I need to test the strength of various bricks by testing their load capacity. As the average brick can hold about 4000 lbs I need a way to apply this amount of force to a brick thats roughly half a square foot. I don't have access to any pressure testing machines with such a large capacity and am frankly puzzled as to how I can get this much weight on such a small area. Any ideas are welcome, Thank you
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Re: Need help applying 4000 lbs of pressure
HI srpatel,
This sounds like an interesting project.
Engineers usually report the "strength" of materials in units of pressure, such as pounds per square inch (psi) or pascals (Pa). 4000 lbs is a force, not a pressure. Pressure is a force per area (e.g., lbs per square inch). Materials also have different kinds of strengths. Two common types of strength are called "compression strength" (or "compression strength") and "tensile strength". Compression strength measures how strong a material is when it is being compressed (shortened, squished, etc.). Tensile strength measures how strong a material is when it is being stretched out.
Looking at a list of the strengths of various bricks/brickwork, it looks like the compressive strength of bricks/brickwork is a few thousand pounds per square inch (psi). The tensile strength, however, is tens to hundreds of psi. Here's the website where I got these numbers:
http://www.engineeringtoolbox.com/compr ... _1352.html
Because pressure is force/area, you could put a much smaller amount of force on a smaller area and still get the same pressure. This is sometimes how machines that test material strength are designed to work. You might check with some construction or brick-making companies in your area (or college/university engineering departments) and see if they might be willing to measure the tensile strength of a few samples for you. Sometimes these companies/schools have machines made specifically to make these types of measurements. Perhaps they would be willing to help you!
This sounds like an interesting project.
Engineers usually report the "strength" of materials in units of pressure, such as pounds per square inch (psi) or pascals (Pa). 4000 lbs is a force, not a pressure. Pressure is a force per area (e.g., lbs per square inch). Materials also have different kinds of strengths. Two common types of strength are called "compression strength" (or "compression strength") and "tensile strength". Compression strength measures how strong a material is when it is being compressed (shortened, squished, etc.). Tensile strength measures how strong a material is when it is being stretched out.
Looking at a list of the strengths of various bricks/brickwork, it looks like the compressive strength of bricks/brickwork is a few thousand pounds per square inch (psi). The tensile strength, however, is tens to hundreds of psi. Here's the website where I got these numbers:
http://www.engineeringtoolbox.com/compr ... _1352.html
Because pressure is force/area, you could put a much smaller amount of force on a smaller area and still get the same pressure. This is sometimes how machines that test material strength are designed to work. You might check with some construction or brick-making companies in your area (or college/university engineering departments) and see if they might be willing to measure the tensile strength of a few samples for you. Sometimes these companies/schools have machines made specifically to make these types of measurements. Perhaps they would be willing to help you!
All the best,
Terik
Terik