Question

hello , i’m supposed to design an experimental setup that has to do with mechanical engineering ( that will help calculate stress or bending moment or any other parameter that has to do with this subject) , the idea is supposed to be simple and clear since we’ll have to realise it in real life later , can you provide me with some ideas since i have no idea about this . thank you

Answer 1

Tensile Test Experiment.

The Mechanical properties of a material is very important determination for any Engineering problem. Strength has many meanings, so let us take a close look at what is meant by Strength and also structure a small experiment that will help us in the determination of the strength and also give a lot more information about the material.

The tensile test is a experiment that involves placing a sample material between two fixtures named "grips" which clamp the material. The dimensions of the material will be known like the length, cross section area etc.

The Test.

The experimental set up involves hanging one end of the specimen that does not move. And then the weights can be added on the free end.

The changes in length of the material and cross section will be noted as the weights are added.

The result of the test is then plotted with load (amount of weight) versus displacement (amount it stretched). The stretch of the material is a function of the material properties and cross section. This will let us determine various properties of the material. Now the force taken by the material in order to stay intact is called stress and the change in the length is called strain. These both parameters can be plotted on the graph and various other technical details about the material behavior can be determined.

To use this stress-strain response for designing structures, we can divide the load we would want the material to hold.

The various points that can be plotted on the graph will be as follows

1) Elastic region

This is the region where the material will return to it's initial state after the load is removed. It's called the elastic region because the material exhibits an elastic behavior.

2) 0.2% offset yield strength

This region is said to be attained when 0.2% of the strain value is reached.

3)maximum stress baring capacity

This is the ultimate load that can be carried by the material. Any load after this the material will not exhibit any elasticity.

4)fracture point.

Where the material fails.