Parapet Effects on Full-Scale Wind-Induced Roof Pressures: Fid-Bau Portal

Parapet Effects on Full-Scale Wind-Induced Roof Pressures

Carter, Russell R. / Smith, Douglas A.

Parapet walls around the perimeter of a building serve several functions including changing the wind-induced pressures on the walls and roof surfaces of the building. To quantify the effects of parapet walls on a building's surfaces full-scale data was collected on the Texas Tech University's (TTU) Wind Engineering Field Laboratory (WERFL) test building with and without a parapet around the entire building perimeter. The WERFL test building is instrumented with 204 pressure transducers connected to taps flush mounted on the surface of the building providing the capability to observe the pressures on the building surface and parapet with a high degree of detail. The pressure taps are positioned on the building surface with two planes of aerodynamic symmetry. The positions allow the pressure data to be reflected about these axes of symmetry thus quadrupling the data set for better resolution of confidence intervals. Three data sets were collected for comparison; WERFL without a parapet, WERFL with a 1.2 m (48 in) parapet, and WERFL with a 85.1 cm (33.5 in) parapet. The data was analyzed based on the summary statistics of the validated pressure coefficients. The pressure coefficients studies are based on 15 degree increments of wind angle of attacks from 0 thru 359 degrees. The effects of the parapets on the roof pressures as a function of the parapet height is presented. Generally the parapets reduced the magnitude of the negative mean roof pressures while the leeward wall parapets contain the airflow creating slight positive pressure on the flat roof of the test structure.