The Structural Design Of Bi-directional Cable Supported Space Grid Structure And Broken Line Analysis

The cable supported space grid structure is pre-stressed space steel structure,which is made up of the grid structure,the pre-stressed cable and the stay-pole.Not only the structure achieve many strange shape and large span structure,but also it can stress perfectly and possess lighter weight.The cable supported space grid structure is widely used in large public projects.Based on the development and the research of of the space truss structure and refer to the actual case of the rail transit integrated control center steel roof in Tianjin,this paper explores the stress performance of four-side slop bi-directional cable supported space grid structure.First,refer to the actual situation of the engineering,using the finite element analysis software Midas/gen.8.36,through making comparisons four-side slop space grid structure,cable supported plan space grid structure and cable supported sloping space grid structure about static and dynamic characteristics,it is concluded that the superiority of cable supported sloping space grid structure in large span and strange shape structure.By the geometric nonlinear analysis of the control displacement method,it is concluded that the influence degree on the horizontal thrust value of the structural bearings,the maximum structural displacement and the maximum stress value of the grid and the cable because of the different sloping at equal altitude and the different prestress value,so the gradient of 8% is the best gradient.The results show that the big influence on the structure because of cable prestress value changed,and the best prestress value of this actual case is discussed.Then,using the construction stage analysis module of Midas/gen 8.36,with the cumulative model for each construction stage,the initial stress and displacement of the structure are analyzed,and the initial stress and displacemen are compared with the results of the design intent.In order to reduce structural safety,it is concluded that the structure of the design phase should be considered as far as possible for construction completion of state of the initial defects.Finally,using the demolition component method,the influence about the displacement and stress of the project is discussed,when the inhaul cable of the roof structure is broken construction during the stage and the using stage.The influence of cable on the structural safety performance is evaluated,the rationality of the structural optimization results is checked.