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Answer: Response-spectrum analysis generates the likely maximum response that a structure may experience in either direction. The deflected shape for a linear-add load combination which contains a response-spectrum load case will display either the minimum or maximum displacements, depending on which has the greater absolute value. Depending on the sign of loads within the load combination, displacement may be in the positive or negative direction, even for adjacent joints.

See also Deformed shape for moving load analysis.

RSA output

How are response spectra and resultant forces obtained for each mode?

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