Residual displacements occur due to the inelasticity of the structural components. Obtaining the residual displacement requires conducting inelastic time history analysis on the structural model. The permanent drifts recorded at the end of the analysis are the residual displacements.

Sir Hamdy Abou-Elfath , I understood the concept and the definition of residual displacement. Sir, my query is that is there any formula or equation to calculate residual displacement? Any Equation? or any parameter formula through which I can drive the residual displacement equation? I want to calculate it numerically.

Hi dear Syed Muhammad Bilal Haider

I think following articles maybe helpful to calculate Residual displacements numerically

In case you are doing nonlinear time history analysis add zeros at the end of earthquake ground acceleration. If the structure has permanent displacements then corresponding to those zeros you will find some values. Then you can calculate the drift from those displacements.