Progressive collapse resistance analysis of secondary shielding installation platform for A-type tank

Abstract
As a key supporting equipment for the construction of LNG carriers, the installation platform undertakes the support and guarantee of LNG carrier tank internal construction. This paper takes the secondary shielding installation platform of A-type tank as the object of study, the study firstly considers the semi-rigidity of the nodes and the material nonlinearity based on finite element software, and then the residual structure is calculated using static nonlinear method after single truss, two trusses and three trusses are invalid simultaneously. The research results show that the truss with higher components importance coefficient has greater impact on the residual structure when the truss is invalid; After the 2 trusses of installation platform become invalid completely, the further progressive collapse will not occur; When A1-HJ, A2-HJ and A2-HJ are dismantled at the same time, it will lead to the local progressive damage, which can cause the collapse of large-scale structures. The research findings can support the design and use of the installation platform.