Interference effects between two tall chimneys on wind loads and dynamic responses

Abstract

The wind loads of two chimneys with different distances and incident angles were obtained by pressure measurement tests, and the results were presented as interfering factor (IF) contours. The interference effects on the across-wind loads were significantly greater than those on the along-wind loads. The dynamic responses of the chimney were calculated using the frequency domain method, and the extreme response interfering factors (RIFs) at different reduced wind velocities were obtained. For the extreme along-wind responses, the most unfavorable incident angle (MUIA) was 105°, and the maximal RIF was 1.3. For the extreme across-wind responses, the MUIA was 15° or 30°, and the maximal RIF was 1.9. Moreover, the combined envelope interfering factors (EIFsc), which were the combined maximal RIFs of all reduced wind velocities, were determined by combining the along- and across-wind responses. Because the equivalent static wind loads are determined based on the structure responses, EIFsc can be used as the IFs of the equivalent static wind loads as guide for wind-resistant designs of actual chimneys.