| 摘要 |
The indirectly prestressed concrete roof-ceiling construction is prefabricated element for constructing industrial large-span buildings. The construction comprises distinctly wide and thin concrete soffit plate (1) and upper concrete girder (2), of the inverse ôVö-shaped cross section, interconnected by slender steel pipe-rods (3) that are used to stabilize the upper girder (2) against lateral buckling and to prevent parts (1) and (2) to get closer or apart each to another. Prestressing of the soffit plate (1) causes compression in the upper girder (2) which passively (indirectly) pushes the ends of the construction, acting on some eccentricity over the center of gravity of the cross section, causing rotation of its ends bending in that way the soffit plate upwards. There are two efficient methods of prestressing these constructions.
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