By making pleats, especially 3.,4. In 1st and 2nd degree seismic zones, we take the iron that we use below in the opening up on the support, that is, we make an economy.... In the 1st and 2nd degree earthquake zones, there is not much economy of the pillar since there will be reinforcements on the support at both the bottom and the top. I think you can use it with peace of mind in 1st and 2nd degree earthquake zones. In any case, the earthquake regulation does not allow us to take into account the contribution of the pleat in meeting the shear force (how much is debatable).