Seismosoft | Earthquake Engineering Solutions

The plastic hinge formation is shown in the code-based checks and performance criteria modules.
In SeismoStruct 2016, instead of the plastic hinges, the elements that have failed are graphically displayed.

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Could it be that you have not selected the beams to be checked for code-based checks and performance criteria? Alternatively, have you checked with hand calculations to make sure that the beams indeed fail?
Note finally that "the Hinges are formed in all structure In beams" only in structures designed with the capacity design philosophy.Not in all structures
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