The Mechanical Behavior Analysis On Large-span Reinforced Concrete Hollow Floor

Reinforced concrete hollow floor is a new kind of hollow plates in which many smallboxes are embedded along the plane of the plates orderly as inter forms. It is widely usedin today’s building with large bay and large column span. Some researches on structuralbehavior of reinforced concrete hollow floor have been done by individual and scientificresearch institutions. However, the lack of thoroughly research on the force mechanism ofthe floor and the mechanical property of the construction members still exists. Therefore,some discussions based on those topics were done in this paper.In this article, the floor systems which used widely in the factual civil engineeringwere summed up comprehensively, and the present numeration of reinforced concretehollow floor in our country were also introduced. The reinforced concrete hollow floorwith box core was modeled and calculated by ANSYS finite element analysis software asa tool in this article. The calculation considered the material nonlinearity of concrete andsteel. Uniform passenger area load which applied to the roof was increasing until the floorwas in full destruction. The effect of each part on stiffness and bearing capacity wasanalyzed with the help of the load-deflection curves from model calculation changing thequantity of reinforcement, the thickness of top board, the width of ribs and the orientationof ribs respectively to put forward some countermeasures. At last, a brief analysis onsimilarities and differences between the reinforced concrete hollow floor with bottomboard and the reinforced concrete hollow floor without bottom board was shown.Conclusion and prospect were given at the end of the article.The research shows that：The mechanical properties of the hollow floor were close tothe plate floor. The top board, the bottom board and the ribs of the floor workedindividually, which made the hollow floor present the performance characteristics ofsandwich plate. The research also finds a positive correlation between the thickness of thetop board and the reinforcement ratio. The mechanical properties of the plate decreasedobviously when the top board was too thin, but the channel of concrete placing couldrelieve this phenomenon effectively. The orientation of ribs had no influence on the floor,which was different from rib floor. The bottom board was not the major control factors ofthe hollow floor either.