Space Work Analysis Of Frame Structure Under Vertical Loads

Reinforced concrete structures or steel structures as bearing system in factory are generally designed according to traditional computational methods of planar frame due to limitations in design theories and concerning approaches. Meanwhile, sectional sizes of structural columns and beams are over enlarged with increasing equipment capabilities because space work of the structural system is not fully understood, lack of reasonable solution. However, with further increased capabilities of factory equipment and concerning loads, this so-called "fatty columns and beams" phenomenon become more and more prominent. Researches on overall space work of factory buildings at home and abroad are often seen, yet few are aimed at structures under vertical loads instead of horizontal loads. The reason may be that vertical rigidity is usually dismissed as small rigidity values of longitudinal connecting bars count little in the vertical plane. But for factory structures under great equipment loads, the space work is shown more or less especially when every horizontal frame is different in rigidity. Based on model test and finite element computation, the overall space work of factory structures is analyzed and researched.The space work is shown only under two conditions: one is that horizontal frames must be connected by longitudinal bars; the other is that every horizontal frame needs to be different in ways such as structure or loads, etc. The internal forces can be calculated for planar frame if every frame is equally loaded and in the same structural form while overall space work under the local loads is greater than that under longitudinally distributed loads. Actually, local parts of the factory house, for example, deoxidization bunker in the main workshop of a heat-engine plant as a frame structure, are subjected to special equipment loads, which are unevenly distributed among every frame. These loads are originally coming from coal scuttle, pulverized coal, desecrator, water tank (including water weight), fineness separator, heator of high and low pressure, pipe support and suspension, etc.Static model test of the multistory fame under the vertical load is carried out to measure loaded behaviors of each frame. Meanwhile, finite element software ANSYS is used for concerning analysis and calculation. The space work of multistory concrete reinforced frame is preliminarily researched with compared results between the model test and ANSYS calculation.Main conclusions can be drawn as below after careful research,Relatively speaking, the space work is not strong under vertical loads, which is only influential for adjacent planar frames.The space work correlates with the position relative to the overall structure in which directly loaded frame locates under vertical loads. If the same frame beam is loaded, overall space work under the concentrated load is greater than that under uniform loads. The change in the rigidity of planar frame has some influence on space work under the vertical load.Factors such as rigidity of longitudinal beam, column spacing of the frame, frame beam span etc. have certain influence on the space work under the vertical load in the normal structure change and concerning rules can be reflected.