roof / roof construction, composite, double prestressed, flat roofed for large span industrial buildings.

摘要

A prestressed, roof-ceiling construction with flat-soffit for constructing an industrial large-span building with a bearing plane-space by assembling pre-fabricated elements. A problem of constructing flat-soffit, finished ceilings in large-span buildings is solved whereby besides an aesthetic ceiling look, the heating volume is reduced, ventilation is ensured and an isolated loft space is provided through which all kinds of installations can be guided. The construction includes a wide and thin concrete plate with a two-part upper, steel construction, interconnected by vertical elements. The construction is twice prestressed by two independent methods. The soffit concrete plate is prestressed centrally in the mould and after the plate concrete is hardened, the upper steel construction is prestressed by pushing apart, at the midspan, the steel separated halves which are then connected. Prestressing of the soffit plate is applied to eliminate or reduce cracks in its concrete while prestressing of the upper construction by pushing apart the steel separated halves is used to control the deflections.