Combination of modal responses in linear spectral method: comparison of different formulae for correlation coefficients

DOI: 10.37153/2618-9283-2021-1-32-42

Authors:  
Rubric:     Theoretical and experimental studies   
Key words: : linear-spectral seismic analysis of structures, correlation coefficients, one-mode responses
Annotation:

Linear-spectral method (LSM) is still the common method for the seismic design analysis. "One-component one-mode" responses, obtained by static analysis in the conventional variant of LSM, are combined twice: first for different modes but for each single excitation component separately, then for the different excitation components. In the alternative LSM variant presented in the Russian code SP 14.13330, first one chooses the "most dangerous" direction of the one-component excitation for each mode; then calculates the "one-mode" response for this excitation, and finally these responses are combined. In both cases the combination is performed using the complete quadratic combination (CQC) rule. Different documents suggest different formulae for the correlation coefficients. In the paper different formulae are compared to each other. The goal is to limit the number of calculated coefficients and decrease the amount of calculations.

Used Books:

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