WIND-INDUCED STOCHASTIC BUFFETING RESPONSES OF BRIDGES BASED ON A VARYING FREQUENCY-INCREMENT SWEEPING METHOD

The fixed frequency increment sweeping method is usually employed in buffeting response analysis when using the complete quadratic combination (CQC) finite element method. Generally, the actual frequency response functions of large structures possess a relatively large value when the frequency is adjacent to a resonant value. Based on this fact, a varying frequency-increment sweeping method is proposed in this study. The CQC method is employed in the buffeting response program. A varying frequency-increment strategy is used in the program in regard to numerical integration. Within the range of resonance frequencies the number of integral points increases automatically while larger frequency increments are employed in ranges far away from resonant points. Both the fixed and the varying frequency-increment sweeping methods have been employed in the analysis of buffeting response for one bridge. The results indicate that the varying frequency-increment sweeping method is less time-consuming and numerically more efficient than its fixed counterpart for the same accuracy requirements.