A New Response Surface Stochastic Analysis Method for Spatial Structure Stability—The Reticulated Shell Structure as an Example

For a long time, spatial structures have been widely used. However, compared with the high strength of their material, their stability is weak, and especially sensitive to damage and defects. This feature has increased the engineering industry’s high requirements for their stability analysis. As we all know, this problem is more prominent for the reticulated shell structure, which is a classic representative of the spatial structure. However, in the current analysis methods for the stability of reticulated shells, the deterministic analysis method cannot consider the random characteristics of defects. Other random methods, such as the random defect modal method, and many improved methods, require more samples and calculation time. This unfavorable situation makes its engineering application greatly restricted. In addition, the random modal superposition method and derivation method based on Monte Carlo has not fundamentally changed this limitation. In order to fundamentally overcome this traditional shortcoming, this paper comprehensively studies the advantages of the high accuracy of the random defect modal method and the improved method, and at the same time, investigates the speed advantage of the response surface method, and then creates a new stochastic analysis method based on the response surface method. Finally, the analysis results of the calculation examples in this paper prove that it successfully balances and satisfies the dual requirements of accuracy and speed required for calculating the stability of the reticulated shell structure. Moreover, it has universal applicability to different forms of reticulated shells, such as classic 6-point flat domes, traditional reticulated shell structures, and bionic reticulated shell structures, and even other types of spatial structures.

Influence of welding deformation on anti-collapse performance of single-layer reticulated shell structures with prestressed cables

In this paper, the ABAQUS finite element software is used to model and analyze the single-layer reticulated shell structure. And the method of removing the constraints of key components is used to analyze the anti-continuous collapse performance of this reticulated shell structure under the action of geometric defects and welding deformation. Welding deformation is mainly caused by welding and prestressed cable tensioning of single-layer reticulated shell. The results show that the removal of the key columns under the reticulated shell will lead to the continuous collapse of the upper part, which leads to the continuous collapse of the whole structure, and the welding deformation can make the continuous collapse of the whole reticulated shell more obvious. Thus determining the influence of geometric defects and temperature shrinkage deformation on the anti-continuous collapse performance.

A Spiral Single-Layer Reticulated Shell Structure: Imperfection and Damage Tolerance Analysis and Stability Capacity Formulation for Conceptual Design

Single-layer reticulated shell structures are widely used, but their stability performance is not ideal. Moreover, they are sensitive to structural damage and imperfections, while the existing conventional design methods of increasing the cross-section, strengthening corrosion protection, and densifying the structural grid are not economical. This study employs a modified and bionic structure—a spiral single-layer reticulated shell structure—to solve the problem. First of all, according to the current Chinese design codes, its mathematical model and geometric model are designed. Then, its damage and imperfection tolerances are analyzed and compared with a traditional single-layer reticulated shell. We then propose a universal bearing capacity formula. Our research conclusions prove that the spiral single-layer reticulated shell structure has a higher tolerance to damage and imperfections while maintaining stability. Moreover, the precise bearing capacity formula proposed will help engineers to efficiently select the structure configurations in the conceptual design phase. Therefore, the spiral single-layer reticulated shell structure is worthy of popularization and application in engineering practice.

Parametric Design and Static Performance Comparison of Six Typical Spherical Semi-open Reticulated Shell

By using ANSYS Parametric Design Language (APDL), this paper compiled the parametric design macro program for six types of single-layer semi-open spherical reticulated shell structure. Parametric design of the six types of reticulated shell structure was realized with given parameters of span S, the vector high F, radial node cycles number Nx, ring to symmetric regional copies number Kn, and the upper removed laps Ns. The stress performance of the six types of reticulated shell structure was compared and analyzed. Modelling examples demonstrated that the parametric design macro program is simple, practical and improves the efficiency of the selection of the reticulated shell design and the stress analysis under different geometric parameters. Through the comparative analysis of stress performance, some conclusions with engineering significance were obtained.

A novel method for rapidly calculating explosion dynamic displacement response of reticulated shell structure based on influence surfaces

In order to analyse the mechanical behaviour of a reticulated shell structure under explosive load, a novel method was proposed to calculate the dynamic displacement response of the cylindrical reticulated shell structure by using the influence surface in this article. First, the theory of the dynamic influence line was developed and the consistency between the dynamic influence lines and the static ones was verified. Then, based on the theory of the dynamic influence line and for the simplified calculation of dynamic responses, the dynamic influence lines of a simply supported beam were simplified as the static ones multiplied by the dynamic amplification factor β. And then the explosion dynamic responses of the beam could be fast calculated using the influence lines. The extended application of the above method to single-layer cylindrical reticulated shell was the influence surface method. The results of numerical examples showed that the nodal displacements of the structure obtained by using the influence surface method agreed well with those obtained by using ANSYS/LS-DYNA. The research results also indicated that the influence surface method was applicable to the node displacement calculation of the structure under three different conditions, including the centre node of the symmetrical structure, the arbitrary nodes (excluding those near the supports) of symmetrical structure under symmetrical loads and the arbitrary nodes of arbitrary structures in which the load holding time is much longer than the natural vibration period of structure. The proposed approach could reduce the computation cost for analysing the explosion dynamic response of the reticulated shell structure, thereby providing a more effective method for the anti-explosion design of reticulated shell structures.