Load calculations for Stability of Slope

[Tygra_1983]

Hi there,

For a coursework that I am doing I am calculating the factor of safety for the stability of a slope. The slope is surcharged by a heavy transporter where the wheel loads on the soil are shown in the image below

Because I am using the method of slices to calculate the slope's stability I multiply and area of the slice by the unit weight of the soil. Hence, I end up with X KN/m^3 * Y m^2 which would give me XY KN/m. The problems comes with the surcharge. Two of the slices are a combination of soil and surcharge (slices 9 and 10) - shown below.

To give me the same result X KN/m^3 * Y m^2 = XY KN/m. I combine 120+110+110+110 = 450 KN/m. I then sum up the area that the wheel loading is acting on. Hence, 0.725 + 1.45 + 2.1 + 1.45 + 0.725 = 6.5 m. Multiply this by 1m into the page so that I end up with 450 KN/m / 6.5 m^2 = 70 KN/m^3. This is so I can treat the surcharge just like the soil and calculate the weight of the slice. So I would end up with 70 KN/m^3 * A m^2 = 70A KN/m - just as how I have done for the slices that are strictly soil.

My question basically is, is this correct?

 

[Tygra_1983]

Anyone??

 

[Tygra_1983]

I have realised what I have been doing is wrong.

So my question is how do I incorporate the surcharge with the slices? The surcharge is in KN/m^2, the weight of each slice (area*unit weight) is in KN/m. I cannot simple add them together, so what shall I do?

Please respond ASAP?

 

[BrianE22]

Is this a Soil Engineering question? I don't know how many Soil Engineers monitor this forum.

 

[Tygra_1983]

Yes, it coursework for my Geotechnical Engineering module.