Redundancy of single-layer dome under earthquake action based on response sensitivity

摘要

Structural redundancy is an important component of structural robustness that reflects the security of the structure under the influence of damage. In this paper, a method based on the response sensitivity is proposed for the assessment of the redundancy of a structure under earthquake excitation, and the response sensitivity is defined as the derivation of element strain to the elastic modulus of the structural materials. The redundancy analysis is carried out for three models of Kiewitt-6 single-layer reticulated dome built at a scale of 1:10 and subjected to earthquake action. The calculated redundancies and the results from the shaking table tests of the three models show that the members damaged by a severe earthquake are characterized by a small redundancy. The redundancy is able to reveal the weak links in the structure, and it represents the importance of the member in the structure. Members with small redundancy are identified as structural weaknesses that are easily damaged under loads, and their failure may cause catastrophic consequences to the dome. Such members are the key components of the structures.