Pushover analysis is a static procedure that uses a simplified nonlinear technique to estimate seismic structural deformations. ... Pushover analysis is commonly used to evaluate the seismic capacity of existing structures and appears in several recent guidelines for retrofit seismic design.

Kindly check your loads, nonlinear static load case, load patterns and plastic hinges.

https://www.sciencedirect.com/topics/engineering/pushover-analysis#:~:text=Pushover%20analysis%20is%20a%20static,are%20shifted%20to%20other%20components.

Thanks! So, basically you mean that they should be identical.

Mr. Ebadi,

These two are not the same thing and should not result in the same pushover curves. Acceleration loads are determined by d’Alembert’s principle by applying a unit acceleration in each direction. For using this as the load pattern, you don't have to do any modal analysis beforehand.

The modal load pattern requires the determination of mode shape and applies the load in the same ratio as that of the chosen mode shape.

I hope that this helps.

I understand that the different failure modes in terms of the sequential hinge formation should be preserved which would be helpful for demonstrating the design adequacy by push over analysis.

Here if the discussion is about load pattern, for mode shape based push, only the corresponding mode will be pushed (in general fundamental mode). When it comes to acceleration load pattern, based on the combination of all modes at every node a spectral acceleration of unity shall be multiplied, hence the force acting at every node will be a function of participation factor of all modes combined with spectral acceleration of unity (which keeps increasing every step), basically a form of multi mode pushover.