TM 5-809-3/NAVFAC DM-2.9/AFM 88-3, Chap. 3
(c) The total moment at mid-height, Mtot, is determined as follows:
Mtot = 40 + 192 = 232 in-kips
(d) The axial compressive stress, fa, is determined as follows (Note: The weight of the top half of
the pilaster is added to P):
Where:
(e) The allowable compressive stress, Fa, is determined as follows:
Fa = [0.18f'm + 0.65 pgFSC]R
=[0.18(1350) + 0.65(0.0246)(24,000)]R = 627(R) psi
Where:
So;
Fa = 627 psi (0.973) = 610 psi
fa = 114 psi < Fa = 610 psi
...O.K.
(f) The flexural compressive stress, fb, is determined as follows (Note: Assume a cracked section):
Where:
d = 15.62 in - 3.5 in = 12.12 in; use d = 12 in.
AsT = The area of the reinforcement that is in tension, which is 3-#9 bars.
AsT = 3(1.00 in2) = 3.00 in2
p = AsT/bd = 3.00 in2/(15.62 in 12 in) = 0.016
np = 21.5(0.016) = 0.344
...O.K.
(g) Check the adequacy of section using only the axial load and the moment created by its
eccentricity (without the 1/3 increase in allowable stresses for wind loading). The flexural compressive stress,
fb, is determined as follows (Note. Assume a cracked section):
9-10
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