Test Analysis On The Seismic Performance Of "+" Shaped R.C. Columns With Angle Steel Reinforced

In 2010, the big difference of the disaster extent between the earthquake in Haiti and Chile, reflects again that the building structure earthquake-proof standards, emergency measures of the social disaster prevention and mitigation, and the awareness to escape for safety of the people, are directly related to the casualties and property losses caused by earthquake. Wenchuan Earthquake in China in 2008, is the one with strongest damaging and biggest affected areas, which caused huge personnel casualties and economic losses.The collapse of building structure, roads and bridges in earthquake will not only result in huge economic losses and environmental damage, but also the vast majority of personnel casualties. The seismic damage of Wenchuan Earthquake sounded the alarm to us once again of earthquake-proof. Therefore, how to achieve the seismic fortification goal of"small earthquake has no consequence, buildings could be repaired in medium one, and buildings couldn't be collapsed in huge one"has always been the explore issues to researchers engaged in seismic.China is still a developing country, as the rapid economic development, the request of building structural seismic performance continues to increase. The use of specially shaped column frame structure is currently promoting, which widely be uesed in high-end residential and hotels, but some of thire own lack in specially shaped columns are also limited the scope of application. In the provisions of the current industry standard,"Technical specification for concrete structures with specially shaped columns", the specially shaped column frame is applicable for a lower height than the general framework.based on the application status of specially shaped columns the in the country, as well as the needs of its development prospects, how to improve the seismic performance of specially shaped column frame and to enhance its scope of application, is a subject which worth exploring in depth. This study moved away from the traditional means which deploy in specially shaped columns with steel plate, steel I-beam and so on, and deployed in the columns with the right amount of angle steel, in order to increase its anti-seismic performance large, with the circumstances of relatively increase a small amount of steel ratio, thereby increased the scope of application of specially shaped column structure. And this study came up with a balance in the seismic performance, economy, as well as the convenience of construction.As the cross-section shaped columns for the object of study, this study mainly for the following three areas of work:(1).This study selected the cross-section columns from the specially shaped column frame. According to the low cyclic reversed lateral loading experiment for 5 model columns (four of them are reinforced by angle steel), it get the failure mode at the combined effect of pressure, bending and shear. Based on the experiment, it analyzed the ductility, hysteretic characteristics, degradation of bearing capacity and stiffness, energy dissipation capacity of the cross-section columns reinforced by angle steel. In terms of the analysis on the influence of the ductility, bearing capacity and deformation capacity of the cross-section shaped columns, by the factors of whether configuration angle, axial compression ratio, with the rate of steel, with steel type and so on. It established the restoring force model of the cross-section shaped columns reinforced by angle steel.(2).It carried out the non-linear simulation analysis of the model columns in the whole test process by ANSYS10.0. Compared to the test results of strength index values at various stages and the stress - strain curves, ANSYS simulation results shown that it matched with the test results well.(3). Finally it came up with many formulas for the cross-section shaped columns reinforced by angle steel about the ultimate bearing capacity of normal sections at eccentric compression, and put forward the concept of adjustment factor for section bearing capacity. By the calculation of one of the test columns using those formulas, and the comparition against the tese results, it shown that the error of the formulas can meet the need of engineering calculation accuracy.The studies have shown that the test columns reinforced by angle steel has a good seismic performance, with a obviously increase. The angle steel worked well with concrete, and in line with the cross-section assumption. The calculation of the ultimate bearing capacity of normal sections and the non-linear simulation analysis are in line with the test models, and provide the groundwork for further study.