| Twisted structure is a structural form in which the floors and facades twisting with the height of structure.At present,there are many practical applications of twisted structural buildings in the world,but there has not yet a systematic theoretical analysis of the structure.The overall performance of the structures with uniformly twisting along height direction was studied in this thesis.The single-layer and 6-layer twisted body twisted structural models are co MPared with the corresponding non-twisted body structure models to analysize the mechanical performance of the twisted structures.The main content of the paper is as follows:1)single-story models of twisted and non-twisted structures are created.The internal force changes of frame columns caused by twisting are explained by theoretical formulas.The internal force of the structure under the rigid floor assumption is co MPared with that under the elestic floor assumption.2)The overall structure behavior of the twisted body is subjected to a static elastic analysis under the design conditions.The dynamic characteristics and displacement response difference between its twisted and non-twisted structures is co MPared.And the overall deformation capacity of the structure is analyzed.3)The co MParative analysis of internal forces of twisted and non-twisted body structure under the action of vertical load,horizontal load and both vertical and horizontal load is carried out respectively.Results showed that vertical load has greater influence on the twisted structures.The internal force co MPare of twisted and the non-twisted structures under the action of vertical earthquake is also studied.4)The elastoplastic analysis of twisted and non-twisted structure under Tianjin wave,Nanjing wave and Tangshan wave earthquake respectively shows that the seismic performance of twisted structure is higher than that of non-twisted structure.5)The influence of steel column diameter,structural twisting rate and plane aspect ratio on the dynamic characteristics and displacement response of the twisted structures is analyzed.6)The research shows that the calculated values of the shear and torque in the columns of twisted structures under the elastic floor assumption are significantly greater than those under the rigid floor assumption,the twisted structures needs to be calculated and analyzed using the elastic floor assumption;for structures with large differences in stiffness along the strong and weak axis,the structural twisting may coordinates the stiffness difference,making the first three-order cycles closer;the twisted structure has a smaller lateral stiffness than the non-twisted structure;beams in twisted structures are greatly affected by the axial force,the axial force and deformation in beams need to be considered;the overall behavior of twisted structures is affected by the vertical load far more than the horizontal load;it may be necessary to take serious consideration of the i MPact of vertical earthquakes in the design of the twisted structures. |
