Effects of upstream terrain characteristics on aerodynamic coefficients of structures

Most research investigations and standards have not emphasized the effects of upstream terrain characteristics on aerodynamic coefficients of structures. Hence in this investigation, pressure measurements study on a 1:2:3 rectangular building model has been simulated through wind tunnel test under uniform, open and suburban terrain condition for 0° and 90° angles of wind incidence. From the variation of pressure and force coefficient values of present study, it is seen that the mean pressure and force coefficient values of all levels of uniform flow condition are on higher side by about 15-40% than the open and suburban terrain values for 0° angles of wind incidence as expected. However the mean pressure and force coefficient values of uniform flow condition are also showed that the values of all levels for 90° angle of wind incidence are on lower side with 20-40% difference than the boundary layer flow values when compared to the values of 0° angle of wind incidence. In addition, the mean pressure and force coefficients of present study has been compared with the Indian and international guidelines to highlight the limitations of codal standards.