Response Of Overshoot And Interference Effect For Building With Opening

According to the survey about the wind damage at home and abroad, the destroyed building structure is not only resulted from external pressure, but also because of the internal pressure of the structure. For the actual engineering, the wind resistant design has to considerate the essential the external pressure of structure. Besides, it is important to think over the wind-induced internal pressure and the relationship between wind-induced internal and external pressure of structure.This article presents the characteristics of wind-induced internal pressure while the building is suddenly opened a hole in the strong wind and responses of wind-induced internal pressure under the conditions of interference by the numerical method and the wind tunnel test, respectively. The theoretical part shows the influence of the wind-induced internal pressure upon different factors of the suddenly opening structure and simulates the empirical equation of overshoot ratio which is treated as the characteristic parameters of the transient pressure overshoot phenomenon. The wind tunnel test part conducts experiment of interference on structure of rigid model of the high-rise-building which has a opening, studies the interference effects of the internal pressure and the correlation between internal and external pressure, identifies the characteristic parameters of the opening in the internal pressure control equation. The main contents are as follows:(1)Numerical analysis about transient internal pressure responses. Under the action of the random fluctuating external pressure, this paper studies three-scale structures(large, medium and small) by the internal pressure transfer equation in detail, investigates the affection of wind speed, background porosity, area of hole and the internal volume to the wind-induced transient internal pressure at 4 kinds of turbulence intensity. All 264 different conditions are considered to calculating the transient internal pressure responses and a fitted empirical formula of the overshoot ratio is given in this paper.(2)Related research on the interference effect of internal pressure response for high-rise building with hole opened. Selecting a typical high-rise building(30 length × 30 width ×180 height), and studying the interference effects of the response of internal pressure and the relativity between internal and external pressure, identifying the characteristic parameters of the opening in one floor of the building(its central location at the height of 0.8h) by changing the opening area, interfering construction position, width and height of the building. Research contents are as follows: a) The internal pressure response in different sizes of opening; b) The correlation between internal and external pressure under different opening positions in monomers and interferential conditions. c) The interference effect of the internal pressure response(the mean, fluctuating and peak internal pressure) while interfering building in different heights. d) The interference effects of the internal pressure response while interfering building in different width. e) The parameter identification: identifying the orifice airflow inertial coefficient CI and opening loss coefficient CL through the internal pressure control equation in the single working condition, and verifying that the opening characteristic parameters also can be applied to the interference conditions.The research about the responses of the internal pressure and the correlation between internal and external pressure is very significant for wind resistant study and design.