The vertical loads on columns in a structure usually depend upon the tributary area and axial stiffness of the columns.

[1] For a given structure, columns supporting a large tributary area and with less reinforcement ratio have more axial deformation due to high loads.

[2] These deformations are further increased when creep and shrinkage are taken into consideration for long term deflection.

[3] This in turn results in differential settlement between two adjacent vertical members (columns/walls).

[4] This differential settlement generates additional moment in horizontal elements & cause axial tension forces in the floor members (beams & slabs).

[5] The effect is more prominent for high rise buildings due high axial loads, hence it is critical to check for column Shortening effect and its impact on slab design.

This is a post on column shortening effect, any suggestions or comments are welcomed.