1. The MC describes the state of stress of our point in the field. That is,...

  

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1. The MC describes the state of stress of our point in the field. That is, the MC shows us the values of the two principal stresses and the value of the maximum shear stress that the point is sustaining in the field. Consider a point in a geostatic soil mass. For our point, o'vo = 100 kPa and o'ho = 40 kPa. Take a sheet of paper and draw the Mohr Circle for this point carefully. 2. Now, we know that o'ho is a principal stress because t = 0 on the vertical plane (in the field). Similarly, ovo is a principal stress because t= 0 on the horizontal plane (in the field). What is the value of t on the plane inclined 45 degrees clockwise from the horizontal? Go ahead and use your drawn MC to find this value. The value should be t = 30 kPa. 3. Note that the value found (t 30 kPa) is the maximum shear stress that the point is supporting in the field, as it is under o'v = 100 kPa and o'n = 40 kPa. Consider now a situation in which o'h remains at 40 kPa, but o'v grows to 120 kPa. Draw this new MC on the same graph you used to draw the MC for item #1 above. If you draw the second MC correctly, you will find that the maximum shear stress that the point is supporting is now 40 kPa. 4. You can now confirm that the maximum shear stress that a point in a geostatic mass feels is equal to the radius of its MC, which is (ov-o'h) / 2. And so, the maximum shear stress depends on how different o' and o'h are. If o'v = o'h, then there is no shear stress felt by the point (the MC is a point on the MC graph; on the x-axis). 5. Neatly redraw the MC you drew earlier for a point with o'y 100 kPa and o'h = 40 kPa. This time draw the MC in the space below. 1. The MC describes the state of stress of our point in the field. That is, the MC shows us the values of the two principal stresses and the value of the maximum shear stress that the point is sustaining in the field. Consider a point in a geostatic soil mass. For our point, o'vo = 100 kPa and o'ho = 40 kPa. Take a sheet of paper and draw the Mohr Circle for this point carefully. 2. Now, we know that o'ho is a principal stress because t = 0 on the vertical plane (in the field). Similarly, ovo is a principal stress because t= 0 on the horizontal plane (in the field). What is the value of t on the plane inclined 45 degrees clockwise from the horizontal? Go ahead and use your drawn MC to find this value. The value should be t = 30 kPa. 3. Note that the value found (t 30 kPa) is the maximum shear stress that the point is supporting in the field, as it is under o'v = 100 kPa and o'n = 40 kPa. Consider now a situation in which o'h remains at 40 kPa, but o'v grows to 120 kPa. Draw this new MC on the same graph you used to draw the MC for item #1 above. If you draw the second MC correctly, you will find that the maximum shear stress that the point is supporting is now 40 kPa. 4. You can now confirm that the maximum shear stress that a point in a geostatic mass feels is equal to the radius of its MC, which is (ov-o'h) / 2. And so, the maximum shear stress depends on how different o' and o'h are. If o'v = o'h, then there is no shear stress felt by the point (the MC is a point on the MC graph; on the x-axis). 5. Neatly redraw the MC you drew earlier for a point with o'y 100 kPa and o'h = 40 kPa. This time draw the MC in the space below.

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The Mohr Circle is a graphical representation of stress states at a point in a material or soil mass ... View the full answer