Pilasters maybe ‘flush’ (in the plane of the wall) or project out from the wall in one or both directions. A vertical element with a horizontal length to thickness ratio greater than 3, used to enclose space. The structural capacity of masonry columns is also affected by eccentricity. Eccentricity may occur due to eccentric axial loads, lateral loads, or the columns is out of plumb.
AXIAL STRENGTH OF REINFORCED MASONRY COLUMNS – Reinforced Masonry Column Design
Ref 1 does not give an explicit definition of a pilaster, it does infer that a pilaster is built integrally with the wall. As you can see these elements may be referred to one another as they all are used to resist axial and flexure. Ref 3 pg 177 limits the effective flange for pilasters to 3x the wall thickness each side of the pilaster however allows for 6x wall thickness for effective flange width on flanged masonry shear walls. In the lower right you can specify the bar size and bar count to be used on each face of the column. Lateral ties are also required to enclose and support the vertical reinforcement. Lateral ties are allowed to be placed in either mortar or grout, although placement in grout is more effective at preventing buckling and results in more ductile behavior.
M3.1 Masonry Pier Design
There are also additional requirements that apply when more than four vertical bars are used.
Check the flexural and shear stress in a reinforced masonry column. Check axial load capacity for masonry column subjected to biaxial bending.
Sel Masonry Column Design
Tour through using the Masonry Column Design module in the ENERCALC Structural Engineering Library.