The Study About The Constitution Technology Of The GBF Cast-in-site Hollow Concrete Beamless Floor Slab

Compared with the flat-slab floor and the waffte floor the cast-in-situ reinforced concrete hollow slab floor system is a new style of floor system, It adapts to the demands for the floor system of this age. The chief property of this technology is that this kind of floor system belongs to the hollow reinforced concrete in which a number of prefabricated permanent high strength thin-wall core boxes are laid.The weight of this floor is small and the span of this floor is large. It can suit multilayer or tall buildings with big column gridding or big spaces,. It can offer users flexible spaces economically, because compared with other floors the deformation of the hollow cast slab has the advantages of lightening selt-weight, strengthening floor slab rigidity, shorten construction duration, improving sound insulation and reducing structure cost. So this new style of floor system will be spread in the future.Although this system has been widely used in some projects and has gained good solial offects, as a new technique, its properties and economic effects have not been comprehended adequately. So the advantages of this special structure are not fully displayed.Based on the above viewpoints, this paper introduces the characters of materials used in GBF high-strength and thin-wall pipe hollow follow floor. GBF thin-wall square core box and GBF honeycombed-core hollow floor. Based upon the analysis of design principles and constitntions of floor, its construction procedure and key points are elaborated.In combination with the engineering examples and a lot of experimental studies, the economical and technical indices of the honeycombed-core hollow floor and the thin-wall core box hollow floor in different load and span are summarized, and the are also compared with the common rib-beam floor frame economically.As a result,the most rational applicable scope has been concluded.Finally, this paper points out several aspects of the present hollow slab floor technology which need improving, puts forward relevant improvement messures and methods of spread the application of this new technology and predicts its future development...