WORLD FOR CIVIL

Combined bending and axial load

Members under combined bending and axial load should be so proportioned that the quantity

P_a/P +M_a /M < 1

where
P_a total axial load on member, lb (N)

P= total allowable axial load, lb (N)

M_a= total bending moment on member, lb in (Nm)

M =total allowable bending moment, lb in (Nm)

COMPRESSION AT ANGLE TO GRAIN

The allowable unit compressive stress when the load is at an angle to the grain is

c’=c (c1 )/[c (sin?) ²+(c 1 ) (cos?) ²]

where c’= allowable unit stress at angle to grain, lb/in ²
(MPa)

c =allowable unit stress parallel to grain, lb/in ²
(MPa)

c1= allowable unit stress perpendicular to grain, lb/in ² (MPa)

?=angle between direction of load and direction of grain