Wind Tunnel Test Of Internal Pressure Of Low-rise Building With Opengings On Wall

The typhoon is one of the main meteorological disasters in China,disaster survey,buildings damaged or collapsed under strong wind force is an important reason for economic losses and casualties.The reason for wind induced damage to the structure of the house is also very complicated,and the effect of internal pressure is one of the most important reasons for the destruction of the building.With the progress of building technology,people's demand for structural safety is higher and higher,and the internal pressure of the building must be considered in the design of the structure.Based on the wind tunnel test,the internal pressure caused by the opening of the building wall is studied in depth.The influence of the wind direction angle,turbulence intensity,turbulence integral scale and opening way on the internal pressure is analyzed.The mechanism of building destruction under the combined action of internal and external wind pressure is revealed,and the results can provide reference for wind resistance design of building structure.In this paper,the wind tunnel test is used to carry out the internal pressure test for the wall openings.Six kinds of grid uniform wind field with different turbulence intensity and turbulence integral scale are debugged.The distribution rule of the wind pressure coefficient inside the building under different wind directions is studied.It is found that the internal pressure of the building basically presents a uniform distribution when the vertical hole is opened.There is a significant increase in wind pressure in the corner of the downstream roof,the corner of the wall and the surrounding area of the open hole,which may have adverse effects on the structure.The internal pressure distributions under different turbulence intensity and different turbulence integral scale are compared respectively.The research shows that the distribution rule of the internal pressure basically stays the same with the increase of the turbulence integral scale,but the wind pressure value decreases.When the integral scale exceeds a certain value,this downward trend becomes weaker.With the increase of turbulence intensity,the distribution law of wind pressure is constant,and the wind pressure value increases,in which the fluctuating wind pressure increases most obviously,the extreme wind pressure is second,and the change of mean wind pressure is the most moderate.The windward wall will generate great instantaneous wind pressure inside the building when it suddenly opens,and its value is usually greater than the maximum wind pressure calculated by the peak factor method.The overshoot ratio of transient internal pressure is enlarged when the turbulence intensity or turbulence integral scale increases,and the influence of turbulence intensity on overshoot ratio is increased more.The correlation of wind pressure in opening buildings decreases with the increase of the ratio of opening area to the vertical wall,When the longitudinal wall is symmetrical opening,the correlation of internal pressure is higher than that of interlaced opening.