The Effect Of The Foundation Rotation Of The Portal-irgid Frames On The Internal Force Of The Upper Structure

In recent years, the application of the light steel type frame has become more and morewidely in our country. At the same time,the destruction accidents of the light steel structurehappened frequently. The deformation of the foundation is a very important reason which can notbe ignored.In past accident analysis, most researchers considered that the settlement deformationchanged the internal force of the structure without considering the influence of the rotation ofthe foundation. The current code for design of the building foundation has clear rules that therotation of the foundation can make the upper structure internal force changed.In the conventional design, we assume that the reinforced concrete column is fixed to thefoundation in general situation. If the foundation is constructed in compressible foundation thehypothesis was set up. But to the independent foundation which are constructed in compressiblefoundation. When bear the upper loads, it will tilt because the load is not absolutely axialcompression. At this time the column bottom is considered as the fixed and is not rational. If stillusing the conventional methods of the design. We will ignore the internal force of some node.That will cause certain node or component to be unsafe. In order to analysis the internal force ofthe component and offer some basis for the noamal design.This paper studied the influence of the rotation of the foundation to the upper structure ofthe light steel portal-rigid frames. This paper is based on the standard and basic theory. It draw aconclusion that which nodes or components will be dangerous. It studied the effect of therotation of the foundation on the upper structure under constant load, live load, wind load andcrane load. It draw a conclusion that under which load the effect of the rotation of the foundationon the upper structure is serious.This peper change the span, height and soil conditions of the light steel portal-rigidframes,and research the rule of the effect of the foundation on the upper structure with thesethree factors turning changes and then draw a conclusion,and offer some basis for the noamaldesign...