A 12 ft. sandy fill is to be added to the saturated clay site shown below. The moist unit weight of thesandy fill is 115 pcf. The data from the consolidation test performed on the clay sample is provided.Sandy fill to be placed 7m = 115 pcf /Consolidation test data10 ftCo = 1.5C = 0.41 sample20 ftC, =0.03Soft clay sat = 112.4 pcfo = 1000 psfBedrock A. Draw a consolidation curve (void ratio vs. vertical effective stress) that illustrates the loading phase of thisclay layer and the unloading phase. Label the key consolidation parameters given in the examples.B. Explain what overconsolidated and normally consolidated means, and how each relates to theoverconsolidation ratio (OCR). Calculate OCR for the middle of the soft clay layer prior to sand loading, yearsafter sand loading (fully consolidated) and years after sand unloading.C. Assuming the bedrock is impermeable, determine the time it took the clay layer to reach 90% consolidationafter sand fill placement and after sand fill removal. Assume cv = 8 e-6 ft^2/s.

Before loadingσ'=112.4-62.4×10=500 lb/ft2After loadingσ'=500+115×12=1880 lb/ft2σc'=1000 lb/ft2

A 12 ft. sandy fill is to be added to the saturated clay site shown below. The moist unit weight of the sandy fill is 115 pcf. The data from the consolidation test performed on the clay sample is provided. Sandy fill to be placed m = 115 pef Consolidation test data 10 ft Co = 1.5 C = 0.4 sample 20 ft C, = 0.03 Soft clay sat = 112.4 pcf o= 1000 psf Bedrock

A 12 ft. sandy fill is to be added to the saturated clay site shown below. The moist unit weight of the sandy fill is 115 pcf. The data from the consolidation test performed on the clay sample is provided. Sandy fill to be placed m = 115 pef Consolidation test data 10 ft Co = 1.5 C = 0.4 sample 20 ft C, = 0.03 Soft clay sat = 112.4 pcf o= 1000 psf Bedrock

Fundamentals of Geotechnical Engineering (MindTap Course List)

5th Edition

ISBN:9781305635180

Author:Braja M. Das, Nagaratnam Sivakugan

Publisher:Braja M. Das, Nagaratnam Sivakugan

Chapter9: Consolidation

Section: Chapter Questions

Problem 9.17P

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