PROGRESSIVE COLLAPSE PERFORMANCE OF SINGLE-LAYER LATTICED SHELLS

In this study, a series of sensitivity assessment indicators were proposed for single-layer latticed shells, based on the bearing capacity of their components. The low redundancy and the stability of single-layer latticed shells were considered. Three single-layer latticed shells with different grid layouts were used to conduct progressive collapse analysis. The distribution patterns of sensitive components and key components of the three shell structures were investigated. The progressive collapse modes of the shells subjected to an extreme snow load were also studied. Results indicate that the grid layout has a great effect on the progressive collapse performance and the failure mode of single-layer latticed shells. The K8 latticed shell and the K8-lamella latticed shell totally collapsed after removing the sensitive components while the geodesic latticed shell with strong internal force redistribution ability remained intact. The progressive collapse performance of single-layer latticed shells can be improved effectively by increasing the sectional area of the key components rather than the sensitive components. The value of the importance coefficient was increased by a maximum of 3 times after considering the initial geometric imperfections, while the position of the sensitive components remained the same. The number of the sensitive components increased significantly and the value of the importance coefficient was enlarged by 1.2 to 5.6 times after considering the buckling of compression members.