Papers by Keyword: Reticulated Shell

Abstract: A stability analysis for a single-layer reticulated shell is presented in this paper. The structural buckling modes and critical loads are calculated first. A preliminary security examination is presented based on the results of linear buckling anasys. And then the load-carrying capacity of this structure would be calculated through the geometric nonlinear full-range analysis. Finally a conclusion is deduced that the stable bearing capacity of this structure has met the requirements of the specification.

Abstract: In this paper, a research is carried on to identify damage of reticulated shell structures based on the combination of modal curvature method and wavelets transform method. Take a scaled model of the reticulated shell structure as an example to analyze, the cross section of one member supposed to have a slight damage of stiffness reduction. In order to locate the damage, modal curvatures of the structure are taken as damage indexes to perform continuous wavelet transform. Results of the numerical analysis indicate that the difference of wavelet transform coefficients of modal curvature can be used to locate damage roughly, while the wavelet transform coefficients of modal curvature difference can be used to locate damage more precisely with easier and more reliable data processing. So it is clear that the damage identification based on modal curvature and wavelet transform is quite effective.

Abstract: To study the effect of various types of defects on the bearing capacity of reticulated shell structures, this paper analyzes the structural nonlinear mechanics performance under physical defects and geometric defects, combining with the matrix displacement method of structure, obtains the impact law of two defects on the reticulated shell structural bearing capacity. Two reduction methods of corresponding defects are put forward which can be used as reference in engineering design and construction. Afterwards, it is pointed out and demonstrated that the safety factor should be defined by a lot corresponding experiments.

Abstract: In this paper, a tangent stiffness matrix of members with end springs of reticulated shell is derived on the basis of Timoshenko’s beam-column theory. In this matrix, joint’s axial stiffness and bending stiffness are considering together, non-linear beam-column element with end springs and rigid ends is taken as the analysis model of members of reticulated shell. In this matrix, not only coupling effects of bending in two axes but also joint’s stiffness and joint’s size are considered, not only the effect of axial force on bending but also the effect of axial force on torsion are considered. Higher order terms in the displacement function are considered. So this matrix is perfect and more precise than Oran’s tangent stiffness matrix. An example of a single layer reticulated shell is provided, which verified the correctness and good accuracy of the present model, and this model can be suited to the non-liner stablity analysis of reticulated shell.

Abstract: An optimum reticulated shell structure is selected and its dynamic properties are analyzed. In this paper analyses the dynamic feature and gains the elementary parameters from the analysis of free vibration. The frequencies and modes are compared by two finite element methods. The paper analyzes the dynamic responses of the reticulated shell structure subjected to two-dimensional and three-dimensional earthquake waves respectively. Simultaneously analyses the linear，geometric nonlinear and both geometric and material nonlinear dynamic responses in two situations. The nodal displacements and stresses of members are compared and analyzed. The characteristics of elastoplastic seismic responses of the structure are revealed and the basic rules are obtained.

Abstract: In order to study the fire-resistance behavior of the spatial pre-stressed steel structures with large span, the model of numerical analysis of a suspended pre-stressed steel reticulated shell subjected to fire load is established with using the software Marc. Based on the model presented here, numerical analysis of thermal response and structural response of the pre-stressed steel structure are computed for the key nodes of the structure. For comparison, the air temperatures near the key nodes are also calculated based on the practical formula of large space air temperature rise. The different location of fire source is considered for analysis of response temperature, displacements and stresses of the nodes of the pre-stressed lattice shell. It is shown that the air temperatures was much higher than the response temperatures of the nodes of the lattice shell during a quite period of time after a fire takes place, and the temperature of the cable nodes are also less than the air temperature near the nodes. It is also concluded that not the cable nearest the fire source but the other cables around the cable fail to work first in the fire.

Abstract: Reticulated shell is one type of the common spatial structure form. This paper proposes a vibration reduction method by supplementing viscous dampers in the reticulated shell. It analyzes the seismic performance on the optimum partial double-layer reticulated shell with dampers by ANSYS soft, gains the stress in the members and the nodal displacements, and compares the dynamic responses between the normal and vibration reduction structure. By means of different parameters, the rules of vibration reduction effect in the reticulated shell with viscous dampers are acquired. It is shown through the calculation that the method developed in this paper is efficient for the dynamic analysis of the reticulated shells.