Answer Happy

QUESTION 2 Slightly overconsolidated clay is located 15 ft below the surface (OCR=1.3). The Cc and Cs of the clay are 0.25 and 0.05, respectively, and Cv=1.5x10-6 ft/min The initial void ratio is 0.45. Please calculate the consolidation settlement. Assuming intact rock underneath clay, i.e., the rock underneath cannot provide drainage path. (Cs=Cw). How long does it take to finish 75% of consolidation?
4p = 1 ksf Sand y = 110 pef, 8 feet Water Table 7 feet Ysar = 115 pcf Clay w = 34%, LL = 50%, Ysar 17 feet 120 pcf
78 79 80 52 53 54 55 56 57 58 59 60 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 0 0.00008 0.0003 0.00071 0.00126 0.00196 0.00283 0.00385 0.00502 0.00636 0.00785 0.0095 0.0113 0.0133 0.0154 0.0177 0.0201 0.0227 0.0254 0.0283 0.0314 0.0346 0.0380 0.0415 0.0452 0.0491 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 0.0531 0.0572 0.0615 0.0660 0.0707 0.0754 0.0803 0.0855 0.0907 0.0962 0.102 0.107 0.113 0.119 0.126 0.132 0.138 0.145 0.152 0.159 0.166 0.173 0.181 0.188 0.197 0.204 0.212 0.221 0.230 0.239 0.248 0.257 0.267 0.276 0.286 0.297 0.307 0.318 0.329 0.304 0.352 0.364 81 82 83 84 85 86 87 88 89 90 91 92 61 62 63 64 65 66 0.529 0.547 0.567 0.588 0.610 0.633 0.658 0.684 0.712 0.742 0.774 0.809 0.848 0.891 0.938 0.993 1.055 1.129 1.219 1.336 1.500 1.781 67 93 0.377 94 95 96 97 98 68 69 70 71 72 73 74 75 76 77 0.390 0.403 0.417 0.431 0.446 0.461 0.477 0.493 0.511 99 100
A.96 years B. 175 years C. 208 years D. 144 years