Study On Overlapping Influence Between Openings Of Reinforced Concrete Chimney

Reinforced concrete chimney, the necessary subsidiary structure of industrial construction, plays an important role in the production. Usually, each chimney has two openings, one is for smoke going inside, and the other is soot door, letting ashes out. When more than one boilers share the same chimney, the number of openings increases accordingly. There will be overlapping influence between the openings. When calculate bearing capacity on horizontal cross-sections, the different situations of no opening, one opening and two openings are taken into consideration. However, there is no universal description when it comes to several openings situation. Under which openings arrangement can we believe that openings are not arranged on the same cross-section, therefore space distance of overlapping influence makes no effort to the result. But to simplify the finite element analysis model and calculating in the past chimney constructions, the existence of the openings is ignored, making the presence of local untrue of the whole model. Therefore, it is a must to study overlapping influence between the openings on the wall of the chimney, as well as to figure out how much area these openings can exert influences and the limitation of overlapping influence.Using finite element analysis software ANSYS, the paper analyses different openings arrangement types of chimney under self-weight. With the von mises stress distribution diagram, through analyzing different locations of the openings and the change of local stress scope respectively, the paper finally achieve to provide some reference for the design of multi-hole layout at the chimney after considering the arrangement of single openings or two openings. The results show that the arrangement of single opening boundary scope changes associated with the size and arrangement of height of openings; when the openings centerline angle is180°, two openings’arrangement decorate the optimal:at a certain opening setting, the adverse impact of overlapping could be ignored.Further, in order to study the stress response of the chimney with openings under wind loads, the paper also sets chimneys of different heights, with single openings’ arrangement under two kinds of wind loads. The results show that:with a single openings layout, the higher the chimney height, as well as the larger of wind load, the greater the stress and strain of the chimney; when two openings centerline angle is135°. the stress distribution is in the best; when the openings is located in the leeward side, it is the most unfavorable position; The chimney with two openings should consider the negative influence of overlap.