Redistribution Calculation

The TBDY2018 code allows redistribution in masonry buildings under certain conditions.

TBDY2018 Article "11.3.6 - Redistribution on each structural wall shall be permitted provided that the shear force on the wall does not decrease by more than 25% and does not increase by more than 33%."

Redistribution can be used in new design analysis and in performance analysis/strengthening of existing buildings.

Redistribution means: when the earthquake force on a wall begins to exceed the wall capacity, the wall does not carry the load above its capacity and displaces, thereby distributing the excess load beyond its capacity to other walls through plasticization. To perform this calculation in the program, the wall stiffness multiplier of insufficient walls is reduced in a way that the shear force does not decrease by more than 25% (approximately 25% or less). In this case, the wall takes less shear force due to the reduced stiffness, and the program distributes the excess shear force that this wall does not carry to other walls in proportion to their stiffnesses.

When this process is performed, the wall that was previously insufficient may become sufficient. However, it should be checked whether the walls that receive the additional load from the insufficient wall have also become insufficient.

The redistribution process should be performed iteratively. After each redistribution, the analysis should be rerun and the results should be checked. The process continues until all walls are within acceptable limits or until it is determined that the building cannot be made sufficient through redistribution alone.