Performance Research Of Strengthened Storey Based On Elastic Analysis And Elastic-Plastic-History Analysis

With the increasing of the height of the buildings, the ability of lateral resistancebecoming a key point in structure designment. When the ability can’t satisfy the designingdemand (for example, buildings codes etc.), for controling the displacement under lateralforces, recent years it is an effective method to add strengthend stories which are much stifferthan usual stories in appropriate locations of the structure. Strengthened storey connects thecore wall and the frame, and makes the two parts work together better. But cause the mutationin stiffness across the whole building caused by strengthened storey, huge interforces can beexist in columns、walls、beams and other components under earthquake. Many scholars havedone a lot of work on this problem and got many results. Now, based on these researches, thefollowing works were done in this paper:1. Taking an built structure as the example, establishing a series of models withdifferent cases. Comparing the displacement、 interforce acquired by elastic analysis.Cause recent researches mainly concentrated on the overall structure effect caused bystrengthened storey, and there’re not enough research on the elements whichcomposing the strengthened storey. According to this, comparing the changes of theforce in columns、beams and trusses. The results shows that the interforce oin thestrengthened storey itself is large, and it should be taking care when designing.2. Cause elastic-plastic analysis can attain better response of structrues under dynamicforces by taking steelbars、concrete damage and steel strain into consideration, usingFEM software to build elastic-plasitc model based on the models in case1andrunning analysis under strong earthquake. First, making sure the models are right,then comparing the damege of the walls、the strain in steelbars and steel beams、damage in floors etc. Finally comaring the results with/without outriggers, drawingconclusions for designment.3. Comparing the results acquired by elastic analysis and elastic-plastic analysis.Acoording to this, we found that the results in elastic-plastic analysis matched betterto the real structure.