A concrete pile is 16 m (L) long and 410 mm x 410 mm in cross section. The pile is fully embedded in sand for which y = 17 kN/m' and ' 30°. Calculate the Example 8.2 For the pile described in Example 8.1) a. Given that K = 1.3 and 80.80, determine the frictional resistance Q Use Eqs. (8.13), (8.24), and (8.25). b. Using the results of Example 8.1 and Part a of this problem, estimate the al- lowable load-carrying capacity of the pile. Let FS = 4. Solution Part a From Eq. (8.23), L-15D 15(0.41 m) 6.15 m 49 D=0.41m pf From Eq. (8.24) at 0, oyl 0, so f 0. Again, at 2 = L' = 6.15 m (17)(6.15) L=6.15m 104.55 kN/m² So Ꭺ fKo, tan 8 (1.3) (104.55)[tan (0.8 x 30)] 60.51 kN/m² Thus Q. - (1.0 + 12-615m) + 1 615m) pl: + furs P (L-L') 0+60.51 L=16m A₁₂ Soil 1 9.85m (4 x 0.41)(6.15) + (60.51) (4 x 0.41) (16-6.15) 305.2977.5-1282.7 kN Calculating the area: Q-PALf=(pf) AL Plot (pf) vs LQ₁ = Area = A + A₂+A3+... c₁ =0 f = Kσ tan S z = 0, σ = 0, f=0 pf = 0 z=6.15m,σ =104.55kN/m² f=1.3×104.5x tan(0.8×30) = 60.51kN/m² p= 4D 4x0.41 = 1.64m pf=1.64×60.51=99.24kN/m = Ą -99.24×6.15 = 305.15kN A₂ =99.24x9.85=977.14kN Q¸ =4,+A₂ = 305.15 +977.14 = 1282.66kN Part b: Q=Q+2=267+1282.7=1549.7 kN Qan = Qu FS = 1549.7 = 387.4kN 4 D= 0.41m pf L = 6.15m A₁ 99.24kN/m L=16m A₂ Soil 1 9.85m 99.24kN/m