| Along with the development of city construction, appeared a lot of new buildings structure form, R. C. frame structure with special-shaped column is one of them, the structure's form gets the expansion with apply in our country many cities with its advantage of not appearing column edges indoors, being easy to arrange furniture arrange, extends effective areas of the room. Based on the past results, seismic behavior of R. C. frame structure with special-shaped column is studied, according to the members to the structure in sequence in this paper. The main contents are as follows aspects:First of all, aiming at the characteristics of special-shaped column, various control parameters including allowable value of drift angle, axial load ratio etc, are studied. On the basis of analysis previous experiment data, it is conclusion that allowable value of drift angle of elastic and elastic-plastic is 1/550 and 1/75 respectively, which is applicable to R. C. frame structure with special-shaped column is given out. The conclusion explains that the deformabiliry of R. C. frame structure with special-shaped column lies between rectangle column frame structure and shear wall structure. The calculating formula of allowable value of axial load ratio of special-shaped column is derived, it is compared with that of equaling areas rectangle column. Through the comparison, it considers that allowable value of axial load ratio of T-shaped section column is smaller than that of rectangle column, and allowable value of axial load ratio of special-shaped column relate to do section size proportion. It has great difference of allowable value of axial load ratio when web and flange are compressed respectively. The loading angle is sensitive to allowable value.Secondly, ductility which is an important index sign to measure the earthquake resistant behavior for special-shaped column under rare earthquake is introduced. The calculating formula of yield curvature and ultimate curvature for special-shaped column is derived, and the calculating formula of the ductility is given when web and flange are pressed respectively. Subsequently simplified calculating formula is presented using the software of Excel with the method of linearity regression, and the calculating formula of the ductility for equaling areas rectangle column is compared with that of special-shaped column, the similarities and differences are found. It is theoretically explained the reason that the deformability of special-shaped column is inferior to that of the rectangle column.The third, according to Code for Seismic Design of Buildings (GB50011-2001), the analysis of R. C. frame structure with special-shaped column is conducted under minor levels of ground motion by means of model analysis method and elastic time-history analysis method. The appropriate maximum stories and the appropriate maximum height of buildings are determined by using the various of control index, such as period , shear-compression ratio, allowable value of drift angle etc when earthquake fortification intensity is 8 degree.Finally, the analysis of elastic-plastic time-history on R. C. frame structure with special-shaped column is conducted by plane structure elastic-plastic time-history analysis the procedure NDAS2D (Nonlinear Dynamic Analysis of Structures in Two Dimensions)programmed in structural system composed of bar, 24 earthquakewaves is adopted according to site classification. The calculating formula of yield surface for special-shaped column and the correspondent program are given in this paper. Thereafter, the position and order about the beam column plastic hinge are drawn; it is considered that the R. C. frame structure with special-shaped column reveals the typical characteristic of "strong column and weak beam". Afterward, the same structure with different earthquake waves is calculated, the distinction is quite obvious in response to time-history of the structure. So when the earthquake waves are chosen, the ones that are close to the soil characteristic condition s...
|
PDF Full Text Request