80_CEG 4012 Notes Fall 2011 CEG 4012 Notes Fall 2011

80_CEG 4012 Notes Fall 2011 CEG 4012 Notes Fall 2011 - =...

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ps3 Summary of Schmertmann Strain Factor Method (CPT): Divide the soil profile into n homogeneous (constant E) layers. Using the depth distribution appropriate for the footing, calculate the strain influence factor for each layer and use the following summation to calculate the settlement: where: C, = correction factor for depth of embedment = 1- 0.5(~)" 0.5 .6.0' z C 2 = correction factor for secondary creep settlement = 1+0.210g" (t",) 0.1 6cr'z = net foundation pressure increase at footing bottom = (q - cr'o) 0'0 = effective stress at footing bottom before any excavation I" = Strain influence factor at mid-height of each sub-layer from idealized distribution shown below Ei = Young's modulus for each sub-layer (estimated from CPT) = 2.5 qCi for axisymmetric footings (UB = 1)
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Unformatted text preview: = 3.5 qCi for strip footings (UB > 10) qCi = cone tip bearing (average assigned to each sub-layer) Ilzi = height of each sub-layer t yr = time in years after placement of footing 0.1 0.2 0.3 0.4 0.5 Iz ,----.--. .--. ...-~,.'::-,--~} I zp = maximum Iz = 0.5 + 0.1~llcr'z , cr' _.. _-_ _-_ _._--_-_ p. .. __ zp , , , I z I~._B_~·lllcr'z = q - cr'o == I , <:-.,. ..1:m!b:i~ri-ill cr'o 8/2 (axisym.) m·,,;am: ?~ ... ·m. B (pI. stra",i",nLJ-r-_-I-__ ~...Ll'-J cr'zp depth to I zp Axisymmetric (UB = 1) Iz = 0.1 at z = I z = Izp at z = 0.5B I z = at z =~BI Plane Strain (UB > 10) I z = 0.2 at z = I z = Izp at z = B I z =0 at z =(413\ , , , , , , , , , , , , /',,-, , , , , 4 1 3 0.5 Z =(zlB) 2...
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This note was uploaded on 02/10/2012 for the course CEG 4012 taught by Professor Staff during the Fall '08 term at University of Florida.

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