Bearing

The allowable unit stresses given for compression perpendicular to the grain apply to bearings of any length at the ends of beams and to all bearings 6 in (152.4 mm) or more in length at other locations. When calculating the required bearing area at the ends of beams, no allowance should be made for the fact that, as the beam bends, the pressure upon the inner edge of the bearing is greater than at the end of the beam. For bearings of less than 6 in (152.4 mm) in length and not nearer than 3 in (76.2 mm) to the end of the member, the allowable stress for compression perpendicular to the grain should be modified by multiplying by the factor

(l+3/ 8)/ l

where l is the length of the bearing in inches(mm) measured along the grain of the wood.