Horizontal/Subsurface Infrastructure & Transportation

Good day,
I am having a bit of a challenge in understanding a few concepts on consolidation settlement. Can you please assist with either the process or workings for the following question.

A layer of this clay 8m thick was preloaded by a 4m thick layer of sand, the unit weight for both soils is 19kN/m3. This was done to facilitate consolidation for the construction of a 5m high embankment whose unit weight is 22kN/m3. The clay layer is underlain by a pervious rock and the value of cv is 4.5m2/yr. The in-situ preconsolidation pressure was 35kPa. a) How much settlement was induced by the surcharge?
Given that Cc=0.548 and Cs = 0.122 and e0= 1.89

Thank you

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Kelvin Marumba S.M.ASCE
Harare
263773023776
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Assume drainage only thru the top layer. Therefore, total thickness of the soil is the drainage height.
Ignore settlement of rock.
Ignore CV as you are interested only in total settlement.
Assume rectangular stress surface equal to embankment pressure.
See complete 8 chapter discussion of settlement and consolidation by Roy E. Olson on Academia:
Chapter 1. Professor Roy E. Olson on Consolidation

http://www.academia.edu/12690488/Chapter_7._Professor_Roy_E._Olson_on_Consolidation

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Chapter 1. Professor Roy E. Olson on Consolidation Academia.edu is a platform for academics to share research papers. View this on Academia >

and
http://parsons.academia.edu/gmcnulty

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Edmund McNulty P.E., P.G., M.ASCE
Senior Engineering Manager
Millersville MD
(410) 729-4091
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