Updating semi-rigidity of joints and boundary conditions of structures using a hybrid finite element

Here, updating finite element model of semi-rigid jointed structures was studied. Firstly, a hybrid finite element was proposed, it was composed of a beam element with two connections at both ends, in order to consider the semi-rigidity of joints with both rotation and shear effect. This hybrid finite element was suitable for model updating, and the stiffness matrix and mass matrix of the proposed element were described. Secondly, a parameterized scheme to update the boundary support parameters was presented. Finally, the proposed hybrid finite element and the parameterized method were experimentally studied by updating the finite element of a 14-bay frame with tested modal parameters. The results showed that the proposed methods were suitable for model updating of semi-rigid jointed structures.