Progressive collapse resistance of single-layer latticed domes under different failure conditions at the same joint

Abstract

A joint connecting multiple members is prone to failure under accidental loads such as blasting, impact, and ice-snow thick cover. A scaled Kiewitt-6 (K6) single-layer latticed dome with a rise-to-span ratio of 1/8 was tested to evaluate the collapse resistance. After three members of the same joint were abruptly removed in succession, the displacements and strains of the remaining structures were determined. The collapse-resistant performance of the identical dome under simultaneous failure (SIF) of the aforementioned three members was analyzed after developing and validating a finite element (FE) model. Finally, the dynamic performance of numerous full-scale K6 domes with different rise-to-span ratios under two failure conditions was investigated. The results indicate that the failure mode of the tested dome under the successive failure (SUF) condition is local collapse. The members connected to the failed joint and other members rely on the beam and compression mechanisms, respectively, to resist progressive collapse. The FE results are well validated by the test results, and the difference between the two conditions is examined via theoretical analysis. Compared with the SUF condition, K6 single-layer latticed domes are more prone to progressive collapse under the SIF condition. A novel collapse model related to the failure conditions, rise-to-span ratios, and loads of single-layer latticed domes is proposed in this work.