Static And Dynamic Performance Analysis And The Shape Optimization Design Of Ridge-type LICS With Large Vector Height

The reticulated shell structures have the characteristics of skeletal structures and shell structures,its stressed uniformly and high stiffness, The advantage is light weight, low steel consumption and construction is simple and fast. Structural modeling is novelty and very artistic expression. The large vector height LICS(Latticed Intersected Cylindrical Shell) is more dynamic and modeling features than traditional lattice shell, has beautiful shape, and can show the Italy Renaissance architectural style.According to the way of connecting rod, ridge-type can be divided into Three-directional grid LICS, Lamella reticulated LICS, Single-diagonal LICS, Fred Boolean type LICS and Double-diagonal LICS. The main work of this paper is:1. According to the space geometric features and ridge geometry equations of LICS, referring to the folded plate latticed shell modeling method and five kinds of typical cylindrical reticulated shell mesh method, the parametric design macro program of five different kinds of LICS (Three-directional grid LICS, Lamella reticulated LICS, Single-diagonal LICS, Fred Boolean type LICS, Double-diagonal LICS) is developed by using APDL; selected a particular arc In the round as the axis of each symmetric sector of LICS, in order to enlarge the small vector problems of traditional LICS; Static loads are applied to this kind of structures. By analyzing and comparing the different vector height, span, the number of the ring, the number of the radial node and the displacement and stress distribution diagram, The effects of the above mentioned factors on the five kinds of LICS are summarized, which provide a new method for the design of LICS.2. According to the geometric characteristics and cylindrical space analytic geometry equation of LICS, The relationship between the micro geometry parameters (The length of the rod, the angle between the rod etc.)and the macro geometry parameters(vector height, span, the number of the ring, the number of the radial node) of the five types of LICS is derived; In the design of the structure, by given the span, the higher parameters, can be introduced into the formula, using the equation to get the function relationship of structure vector high can be concluded that the structure can be guaranteed by the formula, which can reduce the waste of materials and reduce the cost of the project.3. Taking the total weight of the structure as the objective function, the shape optimization design of LICS (Three-directional grid LICS, Lamella reticulated LICS, Single-diagonal LICS, Fred Boolean type LICS, Double-diagonal LICS) is carried out by using the sequential two stage shape optimization design method using ANSYS and FORTRAN software. Through the analysis of the number of the ring kn, the number of the radial node NX and grid forms of division in the optimal structure consumption impact and change regularity of steel, obtains the best combination law of the shell’s main design parameters and provides a reference for the design of this kind of reticulated shell structure in practical engineering.4. The self vibration analysis and seismic response analysis of Fred Boolean type LICS and Three-directional grid LICS is conducted, The modes and frequencies of the two structures are given; Applying EL-CENTRO 3D seismic wave to structure, The vibration characteristics of the structure under three dimensional earthquake are analyzed by the time history analysis method, The time history curves of nodal displacement and the post earthquake displacement distuibution are derived; By calculating and analyzing the changing of span, height, the number of rings, the number of the radial ring and other parameters, the influence of the structure on the post earthquake displacement is analyzed, The seismic response of the two types of LICS1 is obtained, obtainted which parameters has more sensitive influence on the seismic performance, provide a theoretical reference for the seismic design of this kind of reticulated shell in practical engineering.