3 engineering question about shear vs. compressive stress limits

Problem context:

Let's say I'm trying to design a pipe (cylinder) that can stand as much shear force as possible. I'm defining shear force as force that is exactly perpendicular to the pipe, like an upside down "T".

So let's visualize the problem as I'm trying to design a pipe, which, if it's suspended on both ends perfectly, will allow a 200 pound man to stand exactly in the middle of it without the pipe breaking/snapping from his weight (I believe how much weight the pipe can stand is called shear force).

Question 1 - Can you increase the pipe's ability to withstand a man's weight by applying more compression force to it before he stands on it?

For example, let's say that instead of having a pipe made of one solid piece of material, you instead have 10 smaller pipes all aligned and then compressed together with 2,000 pounds of constant compression force. Because the little pipes' material can withstand 3,000 pounds of compression force before they're crushed, the pipe is staying together just fine.

So now let's assume this "combined pipe," which is made up of 10 little pipes, and is held together with 2,000 pounds of compression force. And let's also assuem that the 2,000 pounds of compression force is equally distributed across the length of the pipe...in other words, all pieces of the pipe, whether at the ends, or in the middle, all are under the same amount of compression force...

Question 2 - Let's say we want heaver and heavier men to be able to stand in the middle of the combined pipe without it breaking. All else equal, given the above info, can the pipe handle a heavier man standing in the middle of it, if 2,500 pounds of compression force is applied vs. 2,000 pounds? In other words, does increased compression force equate to higher shear stress limit, in the case of this combined pipe?

Question 3 - What is the equation that would reveal the relationship between compression strength limits and shear stress limits, in the prior question?

In other words, if I want to know how much shear stress a "combined pipe" can take before it breaks, and shear stress is related to compression stress, what's the equation to predict this? What are the variables I need to know?

Chemical Engineering Electrical Engineering Engineering Mechanical Engineering Physics

Project ID: #16449724

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