Effect Of Cast-in-place Slab On The Seismic Performance Of Frame Structure

All previous earthquake have caused serious damage or even collapse construction,especially in the recent512wenchuan earthquake, many column frame structure of thebuilding of the serious damage of concrete, steel bar "necking ", at the end of thereinforcement pulled and at the end of the frame beam end intact damage phenomenon,such as in frame structure, we use "strong column weak beam" designed to ensure thatthe ductility of the structure of the yield mechanism, but in the earthquake disaster,"strong beam weak column" damage occurs frequently, investigate its reason, is thecurrent seismic code also cannot ensure yield "strong column weak beam" mechanismimplementation, because of the filler wall, site casting, reinforced with factors lead tothe increase of the frame beam bending stiffness, made structure "strong beam weakcolumn", among them, the site casting is a very important factor.This article to study from the perspective of site casting slabs yield frame structureunder seismic action mechanism. Was built with the finite element analysis softwareABAQUS plate frame and plate frame model, the lateral displacement loading patternalong the X axis negative direction of the model applying lateral displacement load,analysis in the software after processors have plate frame with steel plate frame beamhogging moment end of negative bending stress and the centre sill side stress of thesteel, by comparison, both have negative bending steel plate frame side beam end andcentre sill end of negative moment reinforcement should be later than the negativemoment reinforcement on frames without plate beam into the yield stage, at the sametime the analysis with rib beam parallel to the stress of the steel plate.Site casting yield mechanism influence factors of frame structure displays in:(1)Beam and centre sill site casting of beam end the contribution of flexuralbearing capacity of the different. Due to the effect of on both sides of the centre sillhave site casting of the framework, the site casting’s contribution to the centre sill sidebending bearing capacity than the contribution of edge beam end bending strength.(2)Thickness will affect the site casting’s contribution in the framework of flexuralbearing capacity. By100,150,200, thick thick thick site casting research, maininfluence of thickness plate bottom reinforcement stress distribution rule. The thickness,the greater the stress of the steel plate bottom is smaller, effective under negativebending plate reinforced the less. (3)Slab reinforcement ratio influence site casting’s contribution in the frameworkof flexural bearing capacity. This paper studies the0.377%,0.671%and1.047%ofreinforcement site casting of slab reinforcement on the top plate reinforcement stressdistribution is not large, the plate steel, steel plate reinforcement ratio affect the bottomstress distribution, by contrast, due to the different plate reinforcement, reinforcementratio affect the top plate of reinforced with steel plate bottom contribution degree offlexural bearing capacity, the slab reinforcement ratio, the greater the top rebar’scontribution to the frame beam end bending bearing capacity, the greater the bottomsteel’s contribution to the frame beam end bending strength is smaller.According to the site casting and calculation formula of effective width and Originsoftware fitting, it is concluded that site casting the suggested values of effective width.