Steel Reinforced Concrete Composite Structure Truss To Strengthen The Structure Analysis And Design

With the rapid development of tall buildings, frame-tube structureswith a strengthened layer have been in more and more use in practicalengineering. Since various problems may occur in setting a strengthenedstory, it is of vital importance to study the mechanical behaviors andfailure characteristics of the structure. Based on former researches and incombination with practical engineering, this thesis systematically studiesthe mechanical behaviors of steel reinforced concrete truss frame-tubestructures with a strengthened story. The main works and achievementsare as follows:1. It gives an introduction to the structure of a strengthened story andthe advantages and application of steel reinforced concrete structures.Also, it introduces existing researches on the structure of a strengthenedstory in tall buildings.2. Through analysis on mechanical behaviors concerning thehorizontal strengthened story of a frame-tube structure, it is known thatthe best position to set a steel reinforced concrete strengthened story isaround 0.6H.3. The strengthened story uses steel reinforced concrete trussoutrigger, which uses beams between the floors as chords and hasdiagonals and vertical members of the truss in proper positions of thefloor, which makes the functions of the floor unaffected.4. SATWE in PKPM is used to build a model of an office building inFuzhou in order to analyze and compare the mechanical behavior, period,and displacement of the structure in all cases. In case No.0 where there isno strengthened story, the maximal story drift and the bottomshear-gravity ratio are not agreeable with the standard while they arewhere there is one.5. Through setting a strengthened story, the horizontal stiffness ofthe structure increases and on condition of an earthquake or a wind, thehorizontal displacement, the maximal story drift and the bottom overturnmoment of frame-tube reduces greatly.6. Through using EPDA in PKPM to do EPDA (Elastic and Plastic Time-history Dynamic Analysis) concerning the structures, the sequenceand position of the ream of various structures are obtained and theposition of the structure's weak story is accurately judged. When there isinfluence of an earthquake, ream firstly occurs on top of the column ofthe frame in the case of rigid strengthened story while in the case of trussstrengthened story, ream firstly occurs on the end of the beams and theyield mechanism of "strong column, weak beam" and "strong inresistance of shear force, weak in resistance of bending moment" alsooccurs.