Transient Wind-induced Internal Pressures And Correlations Between Internal And External Wind Pressures For A Building With Opening

Surveys of wind disasters showed that large part of damages of buildings with opening instrong wind were due to the interactions between the internal pressure and the externalpressure. As a result, considering the action of wind-induced internal pressure and joindaction of the external and intenal pressures in a designing work is necessary.In this paper, the characteristics of the transient wind-induced internal pressure forsudden opening buildings are analyzed in theory. Futher more, a corresponding designequation of overshoot ratio is fitted. Then, a series researches for joint action of the externaland the intenal pressures are studied by wind tunnel test. The main works are focused on thefollowing aspects:(1) Analyzing the transient wind-induced internal pressure in theory. The effects ofseveral factors on the transient wind-induced internal pressure for buildings with a dominantopening are studied in theory. The factors include domain opening parameters(the area andthickness), internal volume, background porosity and wind field parameters (wind velocityand catagery). Then, the overshoot ratio is calculated by using68model cases under randomfluctuating external pressure, and corresponding design equation is fitted.(2) Researches on the joint action of the internal and the external pressures. Pressuremeasurement wind tunnel tests on a rigid high-rise buildings is for the net pressure analysis.Analyze the effects of wind direction on area-averaged net pressure and get the worstdirection of each wall. The effects of various factors incluindg opening area, openingthickness, back porosity on joint action of internal and external pressures are studied.(3) Helmholtz resonance under oblique wind flow. On the basis of wind tunnel tests, thispaper deals with an investigation of the phenomenon of Helmholtz resonance under obliquewind flow, and find the wind angles on which Helmholtz resonance could happen. Then,analyzing the effects of wind velocity on Helmholtz resonance.(4) Identification of domain opening farameters. On the basis of wind tunnel tests of arigid high-rise building, the paper analysis the characteristics of wind-induced internalpressure and getting a reasonable domain opening parameters by comparing the resultcalculated by wind tunnel test to the result in theory.