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Along with the promotion of green construction, prefabricated single-layer reticulated shells (PSLRS) with assembled joints have been increasingly applied in large-span buildings. However, the frequent joint assembly errors during the manual installation will not only weaken the mechanical properties of the joints, but also affect the overall stability of PSLRS. Therefore, the adverse effects of joint assembly errors on both aspects were studied in this paper. Firstly, the flexural performance of a modified bolted splice joint was numerically simulated, and its performance degradation under different joint assembly errors was investigated. Then on this basis, the PSLRS computational model with the joint performance imperfections was established, and three imperfection analysis methods, J-SIMM, J-CIMM, and J-EIM, were proposed to estimate the reliable bearing capacity. Based on these methods, the most unfavorable imperfection distribution modes of cylindrical PSLRS were obtained, and the imperfection sensitivity under different boundary conditions was analyzed. The results showed that the initial joint assembly errors significantly reduced the joint's flexural stiffness and ultimate bending moment, thereby changing the buckling mode of PSLRS and leading to premature structural failure. Especially for the cylindrical PSLRS supported at the two longitudinal edges, its stability bearing capacity was significantly reduced under the influence of initial joint performance imperfections. Nevertheless, the proposed method J-EIM still obtained the lower limit of the bearing capacity with fewer calculations compared to the stochastic method, which provides practical guidance for the structural design of PSLRS. [Display omitted] • A modified bolted splice joint that can connect large-section latticed shell members was proposed. • The flexural performance of assembled joints was investigated with the initial assembly errors considered. • The sensitivity of prefabricated single-layer reticulated shells to the joint performance imperfections was analyzed. • Two deterministic imperfection mode methods of the joint performance were proposed for the reliable bearing capacity. • The coupling effects between the joint performance imperfections and geometric imperfections were studied. [ABSTRACT FROM AUTHOR]

Abstract: Investigation of elasto-plastic stability of reticulated shells has gradually become more and more attractive to researchers. However, the analysis of the elasto-plastic stability is much more complicated than the elastic analysis, because of the involvement of both the geometrical nonlinearity and the material nonlinearity and the interactions of the two. Taking into consideration of material nonlinearity, the elasto-plastic stability behaviour of reticulated shells will be significantly different, which can only be revealed by large amount of geometrically and material nonlinear analysis of the structures. The elasto-plastic stability of seven types of commonly used single-layer reticulated shells (Kiewitt-8, Kiewitt-6, Geodesic, Schwedler Bidirectional, Schwedler Monoclonal, Sunflower, and Radial Rib) was investigated systematically with ANSYS, in which more than 2000 cases of geometrically and material nonlinear analysis were conducted with different initial geometrical imperfections, geometrical, structural and load parameters. Based on the analytical results and via comparison between elastic and elasto-plastic buckling loads, the plasticity influence coefficients were summarized for each type of the reticulated domes. These coefficients can be used to predict accurately the elasto-plastic buckling load in design practice of the reticulated domes, which is an easy way for designers to evaluate stability of the reticulated shells. [Copyright &y& Elsevier]

This paper proposed a novel buckling restrained steel plate shear wall (simply referred to as XSPSW) composed of X-shaped restrainers, an infill steel plate, and boundary restrainers. The X-shaped restrainers are placed on both sides of the infill steel plate, and the infill steel plate is divided into a series of diagonally arranged square subplates with a small height-to-thickness ratio. The X-shaped restrainers can effectively restrain the shear bucking of the infill steel plate and improve the seismic energy dissipation capacity of the shear wall. A refined numerical analysis model of the unstiffened steel plate shear wall (USPSW) and XSPSW was established and the validity of the model was verified by experiment. Numerical analysis was conducted to investigate the force mechanism and hysteretic behavior of the XSPSW. The results demonstrate that the mechanical behavior of the XSPSW is controlled by the square subplate. Compared to the USPSW, the shear buckling capacity, peak load, and energy dissipation capacity of the XSPSW are higher by at least 17%, 5%, and 7%, respectively, and the constraint efficiency of the out-of-plane displacement is larger than 55%. With the decrease in the height-to-thickness ratio of the subplate, the improvements in the shear buckling capacity, peak load, and energy dissipation capacity are increased to 29%, 31%, and 20%, respectively. Moreover, the constraint efficiency of the out-of-plane displacement rises to 92%, and the hysteretic curve tends to be full. The influence of the height-to-thickness ratio of the infill steel plate on the bearing capacity and energy dissipation capacity of the XSPSW is less than 2.5% and 1.2%, respectively. • A novel lightweight buckling restrained steel plate shear wall with X-shaped restrainers (XSPSW) is proposed. • An effective refined numerical analysis model of XSPSW is established. • The mechanical behavior of XSPSW is controlled by the subplate. • The X-shaped restrainer can effectively improve the hysteretic behavior of SPSW. • As the height-to-thickness ratio of subplate decreases, the hysteretic behavior of XSPSW increases significantly. [ABSTRACT FROM AUTHOR]

Single-layer reticulated domes are typical structures with high degree of static indeterminacy. The stability of the reticulated dome structures is complicated and closely related to both the member buckling and the overall buckling of the structure. However, little theoretical research work deals with this very complex phenomenon. Meanwhile, for the statically indeterminate structures, it is a common belief that the local failure would occur first and result in the change of internal force paths, while the structure could support load continually before the overall collapse of the structure. In this paper, the interaction between the member buckling and the overall buckling of the structure was investigated, and this common belief was explored. The geometrically and materially nonlinear analyses (GMNA) were carried out for the reticulated domes with eight types of different grid forms, and the examination of member buckling for each dome was conducted based on the examination method of the P – δ end curve or the P – δ mid curve of the member. The relationship between the member buckling and the global instability of the structure was obtained by evaluation results of member buckling. Consequently, for the common reticulated domes, two instability patterns were identified, i.e. progressive instability and synchronous instability. In the case of progressive instability, the member buckling occurs in advance of the overall buckling of the structure. Then the number of the instable member increases, and finally the overall buckling of the structure occurs. In the case of synchronous instability, the member buckling and the overall buckling of the structure happen simultaneously. The interaction mechanism between the member buckling and the global instability of the structure was analyzed for both instability patterns. [ABSTRACT FROM AUTHOR]

Abstract: Initial curvature of members is an inevitable geometrical imperfection for reticulated domes. To investigate the stability of single-layer domes with initial curvature of members, the multi-beam method was presented to simulate the initial curvature of members, and two modeling methods were adopted to introduce the initial curvature of members for reticulated domes by means of ANSYS. First, the random imperfection mode method was introduced according to the randomness of initial curvature of members. The example of a Kiewitt-8 dome was used to explain the method and investigate the influence of angle and amplitude random variables on the stability of reticulated domes. Second, the modified consistent imperfection mode method was obtained, which was an efficient method to evaluate the lowest buckling load of the structure with initial curvature of members. Based on this method, the Kiewitt-6 and Kiewitt-8 single-layer reticulated domes were taken as examples to analyze the stability of structures with initial curvature of members, and the influences of initial curvature of members on the ideal structure and the structure with nodes deviation were obtained quantitatively. The results show that, for the ideal structure and the structure with nodes deviation, initial curvature of members can decrease the buckling load of the structure obviously. Initial curvature of members can change the buckling mode and plasticity development of the structure. The influence of initial curvature of members on the elasto-plastic stability of single-layer reticulated domes cannot be neglected. [Copyright &y& Elsevier]

Abstract: In order to understand the influence of member buckling on the stability of reticulated shells, a key problem of how to distinguish the member buckling for reticulated shell structures was pointed out, and judgment methods of member buckling were obtained. Using a Kiewitt-8 dome as an example, the buckling characteristic and propagation rule of member buckling were studied. Meanwhile, a reticulated dome model tested was analyzed and compared by using the finite element software ANSYS. Judgment results of member buckling and the influence of member buckling on the structure were obtained. The judgment results accorded well with the test. Then taking the member buckling into consideration, the effect of material nonlinearity, initial geometrical imperfections, and member size on the stability of the members and the reticulated shell structures were investigated. The results show that the methods adopted can judge the member buckling for reticulated shell structures effectively; the member buckling and its propagation can affect the stability of the structure directly. [Copyright &y& Elsevier]