Study On Wind-induced Internal Pressure Of Cylinder Coal Shed

With the development of national power industry,chemical industry and coal industry and the increasing attention to the dust environmental protection,cylindrical coal shed with large capacity has become one of the first choices for coal storage.Due to its light deadweight,large flexibility and small damping,wind load is usually one of the main factors to control the safety of structures.For opening or partially opening cylindrical coal sheds,wind-induced damage is largely caused by the synergistic action of internal and external pressures.At present,the research on cylindrical coal shed mainly focuses on single span and double spans with equal height in structure,and mainly focuses on external pressure and synthetic wind pressure in wind resistance,while the research on wind-induced internal pressure is still in the preliminary exploration stage.In this paper,the research status of wind load in cylindrical coal shed is summarized,and the characteristics of internal pressure distribution in the structure under different openings are summarized.After that,the wind load characteristics of the inner surface of cylindrical coal shed under different end closure forms and lengthwidth ratios are discussed by the wind tunnel test of rigid model.The main contents in this paper are shown as following:1.This paper has completed the wind tunnel test of cylindrical coal shed with the length-width ratios of 0.6,1.2,1.8 and the opening,semi closed and closed forms of the ends.There are 15 load cases in total.2.The impacts which are exerted on the wind-induced internal pressure of the major structure by the different forms of the ends and length-width ratios are studied.The results show that when the inlet flow is perpendicular to the longitudinal axis of the coal shed,the wall in the end enhances the correlation of pulsating wind pressure.Other forms except the closed end have little influence on the power spectrum.The increase of length-width ratio leads to the increase of the absolute value of average wind pressure and the increase of the correlation of pulsating wind pressure in downwind direction,but the weakness in the transverse wind direction.When the inlet flow is perpendicular to the horizontal axis of the coal shed,the absolute value of the wind pressure coefficient increases with the increase of the degree of closure.When the windward end has a wall and the leeward end is open,the average wind pressure is negative,the pulsating wind pressure is highly correlated in the downwind direction and less affected by the ventilation rate of windward side.When the windward end is open and the leeward end has a wall,the average wind pressure is positive,the pulsating wind pressure is enhanced and highly correlated on the whole,the contribution of low frequency to wind pressure pulsation energy is dominant.3.The extreme value variation rule of the cladding structure at different positions under all-wind direction is studied.The results show that with the increase of the accessory area,the area-averaged extreme value of wind pressure of the cladding decreases.The greater the degree of the end closure or the larger the length-width ratio becomes,the lower the attenuation rate of the area-averaged maximum value in the corner gets.Finally,this paper gives the area reduction coefficient of working conditions.4.This paper gives the design value of wind load of the major structure and the cladding in different kinds of Cylinder coal shed.