Design method of uniform loading system using airbags in structure test

Aiming at a new structural loading type by airbags, the paper establishes the mechanical model of airbag loading system and discusses some key points, showing that, the surface tension of airbags should be eliminated in the direction of large curvature of the loading surface, but the elimination of surface tension is not necessary in the direction of small curvature. To reduce the experimental cost and facilitate experimental observation, surface tension is restrained by boundary isolation rather than the traditional way of metal containers. Then a corresponding discipline of loading control is designed as well as an approach of system verification. The feasibility of airbag loading system has been demonstrated by a model test example of aircraft fuselage frame.