Safety assessment of existing pin-jointed grid structures with crooked members using static model updating.

• Static model updating can obtain the practical structural model in zero-load state. • The behavior of damaged structure is well simulated using the updated model. • Different factors can cause member deformation and different stress state. • Member deformation can result in the premature failure of compression member. In pin-jointed grid structures, the commonly observed bending deformation of members affects the structural performance. The main aim of this study is to investigate the residual load-bearing capacity of an existing pin-jointed grid structure with crooked members, and a new model updating method using static measurement data is proposed to obtain a practical numerical model of the structure. First, the vertical displacements at multiple positions in the structure and the bending deformations of crooked members are selected as the static measurement parameters and measured. Then, the structure, including the crooked members, is adjusted from the load state at the moment of measurement to the zero-load state through global optimization. Finally, the updated finite element model with crooked members is utilized to assess the residual load-bearing capacity of the overall structure. In this study, a load experiment using a quadrangular pyramid grid structure with artificial crooked members is conducted, and the experimental results validate the proposed method. [ABSTRACT FROM AUTHOR]