Reliability Analysis And Construction Simulation For Cable-Struct System

A new space structure named cable-strut system, basically composed of cables and struts, is stiffed by prestress. Tensegrity systems, cable domes and cable-strut structures all belong to this system. With rapid development of national economy and design method, cable-strut systems are applied widely in sporting fields, exhibition halls and large stores. Researches on form-finding, prestress determination, static and dynamic behavior of the system are also carried out extensively. But most of current studies regard cable relaxation as the criterion of the structural invalidation, and behavior after cable relaxation and reliability of cable-strut system are less considered. Construction analysis of cable-strut system is the hot and difficult research spot in domestic and foreign. However, current researches are major on cable dome but seldom on suspen-dome. On the basis of available work, respectively taking cable dome and suspen-dome for example, researches on reliability and construction of cable-strut system is presented in this thesis. The following are the main points:Based on literatures, sorts of space structures and characteristics of cable-strut system is first introduced and development history, project application and present situation briefly described. The main contents of the thesis are then proposed.To investigate the behavior of cable-strut system after one cable (strut) ruptures, kinetics method was adopted to simulate the variety of internal force of other members and final equilibrium position of the structure after failure of different members. The safety of the structure is evaluated and the safety grade of members in different positions is distinguished by observing whether the failure of partial cable (strut) causes progressive collapse of other members which brings continuous collapses of the structure.The reliability of structure means the realization probability of the predefined function during service period with stipulation conditions. Using response surface method and Monte Carlo Method combined with the probability analysis modules ofANSYS, the probability of cable-strut system is analyzed as well as the confidence level of structure in the modes of displacement invalidation and stain invalidation respectively. The sensitive variables to the different mode of structure invalidation are also provided.In construction of suspend-dome, the sequence of pretensioning diagonal cable from outside to inside is adopted. The process is simulated by inverse analysis and the control values including members' force and nodal coordinates in each step of construction are obtained, which can effectively instruct the construction of real project.At the end of this thesis, some conclusions are summarized, and the problems that should be studied further are put forward.