Question

# Solve the following problem. A site is underlain by two layers. The top layer is an 10m thick layer of clay with OCR= 2, friction angle = 36 degrees, and

Su = 50 kPa. The bottom layer is a 6m thick layer of sand with OCR = 1, and fiction angle = 38 degrees. Bedrock lies below the sand layer. In fact, assume that the UC test presented in the video (from problem #1) was conducted on a core extracted from our site. The nano CT of that core showed no internal flaws (i.e., no weathering), and a value of X = 2 has been assigned to it. The structural engineer for the project has indicated that each pile must support a downwards load of 850 kN. You have selected to evaluate drilled, rough concrete piles with diameter B = 1m as possible alternatives: a.Alternative #1 (start on a new page; draw the profile with the pile):D = 7m. Find Qult ST and Qult LT. b.Alternative #2 (start on a new page; draw the profile with the pile): D = 11m. Find Quit ST and Qult LT. c. Alternative #3: (start on a new page; draw the profile with the pile): D = 16m (rests on rock). Find Qult.

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