Stability And Earthquake Resistance Analysis Of The Parabolic Arch Structure

As one of the structures bearing load well and safely, arch structure has the advantage of long span, high capacity, small cross-sectional dimension and small deformation in comparison with bending-shear structure, therefore, it is widely used in the field of mechanical engineering, aerospace engineering, civil engineering and so on. But with the increase of span, cross-sectional dimension is larger and larger, and shape is more and more complex and diverse. As the rationality of the design directly affects the carrying capability, stability and the weight of arch, it is of great importance to design an arch structure of considerable stability. Taking the inverted trapezoidal parabolic arch structure as an example, this paper uses the finite element method to analyze the elastic plastic stability of the arch structure. Besides, thanks to the complexity of the dynamic characteristics of large-span arch structure and the multiplicity of factors on the seismic response, it is easier to carry out seismic analysis of arch structure by finite element method.Taking the inverted trapezoidal parabolic arch structure as an example, this paper presents the study on in-plane and out-plane stability capacity of parabolic arch subjected to radial uniform load, vertical uniform load and concentrated load by employing ANSYS. The full in-plane buckling load-displacement equilibrium path and out-of-plane buckling load-displacement equilibrium path are theoretically investigated by using finite element approach in conjunction with the arc-length method. The law of elastic-plastic buckling of parabolic arch structure is analyzed under different rise-span ratios and supporting conditions, considering the influence of various factors, such as material nonlinearity and initial geometric imperfection.Natural vibration characteristics of the arch structure is determined by the type, stiffness, mass distribution, material properties and connection structure of system structure etc, therefore, it varies with span ratio and connection structure. In this paper, modal analysis of parabolic arch structure is carrying out with different cross-ratios and the supporting conditions to analysis their impacts on the natural cycle of arch structure.Seismic response analysis of parabolic arch structure subjected to horizontal transverse, horizontal longitudinal, horizontal transverse and vertical, horizontal longitudinal and vertical seismic wave is carrying out by response spectrum method and time history method to discuss the impacts of span ratio and connection structure on displacement response of arch structure.