Study On S Dynamic Properties And Stability Of Pre-Stressed Ribbed Dome

After reviewed the development and actuality of dome structure,A new type of pre-stressed ribbed dome was presented in this thesis. This structure has the both virtue of common dome and cable dome-its concision,its high capacity and its easiness in construction,and so is a potential new type of spatial structure. In this thesis,the dynamic behaviors and geometrical nonlinear stability have been studied,and these conclusions have been put forward.At first,free vibration characteristic of the structure is analyzed,and it is discovered that the frequencies are denseness,moreover vertical vibration is dominant,the combination of ribbed truss and pre-stressed cables enhanced the structure's stiffness in some degree.And then,the structure's dynamic behavior has been investigated and calculated with spectrum and time-history methods,and obtained the conclusion that time-history method should be employed. Afterward,element internal forces and node displacements under the EL-Centro are studied by time-history method,the conclusion was obtained that the pre-stressed ribbed dome structure has a good dynamic performance,but at the same time,it's been pointed out that the pre-stress is necessary to structure,without it,the structure may be destroyed. Furthermore,after parameter analysis,the following results are obtained:the effect of rise-to-span on the structure's dynamic internal forces is distinct,while the effect of mass parameter is little.Then the effect of cable arrangements to the structure dynamic behaviors was studied. The free vibration frequencies and dynamic internal forces of seven types of cable arrangements were calculated,and the conclusion that diagonal cables are sensitive to structure stiffness are obtained.At last,geometrical nonlinear stability analysis of the pre-stressed ribbed dome was investigated. The linear solution and nonlinear solution were compared,the structure's obvious geometrical nonlinear character was found. Then the buckling analysis of the structure was made,and compared corresponding dome,the conclusion was made that ribbed truss and pre-stressed cables improved the structure's limit buckling load. At one time,the buckling analysis of structures with different rise-to-span were made,and discovered that buckling load and stability can be improved with high rise-to-span.