The Study On Determination Of One-way Or Two-way Slabs Simply Supported On Four Sides

Elastic thin slab is widely used in all engineering field as a crucial form of structure, which can be divided into one-way slab and two-way slab in principle determined by adjacent side ration (less than 3 is two-way slab) according to the newly published Code for design of concrete structures (GB 50010-2002), The classification originates theoretically from Marcus method of slab strip specifying that loads are transferred in two directions for the elastic thin slab subjected to uniform loads. In this paper, great difference has been found in the analysis of load transfer mechanism contrasted with Marcus under the same circumstances. Furthermore, new computation rules classifying elastic slabs and concerning reasonable basis are proposed through the analysis of the loading mechanism of slabs simply supported on four sides subjected to uniform loads.Slabs simply supported on four sides subjected to uniform loads are taken as the main subject in the analysis. First, problems in the Marcus method of slab trip is pointed out, which lies in great variance between assumed computation model & loading model and real structural mechanism, resulting in inaccuracy of load transfer. Then various solution methods based on elastic than slab are discussed to obtain theoretical solution of slabs simply supported on four sides subjected to uniform loads, which, internal forces distribution rules with different ratios of adjacent sides. Meanwhile, large finite element software ANSYS is used for loading behavior analysis to understand the rules of loading effect varying with different rations of adjacent sides for slabs simply supported on four sides subjected to uniform loads. These rules can be a reference for judging whether the slab simply supported on four sides is one-way or two-way.Finally, the determination that divides whether the slab is on-way or two-way is clearly proposed with ratio of adjacent sides length less than 3 or not, based on rules varying with different ratio of adjacent sides length that reflect bearing forces distribution and moments distribution in the plane for the simply supported slab on four sides under uniform loads...