Chapter 17 788 17.3 Fig. Prob. 17.3 shows a drilled pier with a belled bottom constructed for the foundation of a multistory building. The pier passes through two layers of soil. The details of the pier and the properties of the soil are given in the figure. Determine the allowable load Q, for F= 2.5. Use (a) Vesic's method for the base load, and (b) the O'Neill and Reese method for skin load. L= 15 m d=1.25 m Soft to medium stiff clay c-25 kN/m² y= 18.5 kN/m N=4 1,75 Figure Prob. 17.1 Layer 1 d=3ft 30 ft c. - 600 lb/ft² Clay 10 ft T I 3 ft 6ft Layer 2 Clay c,-2100 lb/ft² Figure Prob. 17.3