Substructure Hybrid Simulation Boundary Technique Based on Beam/Column Inflection Points

Abstract

Abstract:Compatibility among substructures is an issue for hybrid simulation. Traditionally, the structure model is regarded as the idealized shear model. The equilibrium and compatibility of the axial and rotational direction at the substructure boundary are neglected. To improve the traditional boundary technique, this paper presents a novel substructure hybrid simulation boundary technique based on beam/column inflection points, which can effectively avoid the complex operation for realizing the bending moment at the boundary by using the features of the inflection point where the bending moment need not be simulated in the physical substructure. An axial displacement prediction technique and the equivalent force control method are used to realize the proposed method. The numerical simulation test scheme for the different boundary techniques was designed to consider three factors: (i) the different structural layers; (ii) the line stiffness ratio of the beam to column; and (iii) the peak acceleration. The simulation results for a variety of numerical tests show that the proposed technique shows better performance than the traditional technique, demonstrating its potential in improving HS test accuracy. Finally, the accuracy and feasibility of the proposed boundary technique is verified experimentally through the substructure hybrid simulation tests of a six-story steel frame model.

Model updating method for hybrid simulation based on global sensitivity analysis

“…In many cases, the HS needs to simplify the boundary conditions and even relinquish some of the degrees of freedom of the boundary. [6][7][8][9] Therefore, differences in the form of the model of the NS and incomplete boundary conditions of the PS are two key problems that affect the accuracy of the HS. The hybrid simulation model updating (HS-MU) is an important method to solve these problems by using physical testing data of the PS to update the NS model.…”

“…However, for large structures, the number of exposed degrees of freedom of the boundary is usually larger than the number of actuators that a laboratory can offer. In many cases, the HS needs to simplify the boundary conditions and even relinquish some of the degrees of freedom of the boundary 6–9 . Therefore, differences in the form of the model of the NS and incomplete boundary conditions of the PS are two key problems that affect the accuracy of the HS.…”