Influence of joint assembly errors on stability of prefabricated single-layer reticulated shells

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.