Reliability Analysis Of Cable Dome Structures Based On Response Surface Method

It needs further research that whether the reliability of the cable-strut tensegrity structures which designed by the traditional method can meet the code or not, as its differences with traditional stiff structures in mechanical behaviors. In order to study the reliability of the cable-strut tensegrity structures in limit state, the response surface method is used to analyze the structures reliability and a Matlab program is developed to realize the object.Structural reliability theory and methods are introduced in this paper, and considering on the structural characteristics of cable-strut structure, a Matlab program about response surface method (RSM) is developed to calculate the structural reliability index.The reliability indexes of a Levy cable dome are calculated with the Matlab program under wind load and snow load respectively. In order to verify the response surface method having enough precision, the reliability indexes calculated by RSM will be compared with results calculated by ANSYS with Monte Carlo method. The calculation results reveal that the reliability index in the failure mode of cable slacking can not satisfy the code and become the principal failure mode of the cable dome.The influences of some parameters on the structural reliability have been analyzed, such as the influence of prestress on structural reliability index, the effect of load distribution pattern on structural reliability index, and the impact of different displacement control on displacement reliability index. These analysis results will provide guidance for optimum structural design.