Research On Mechanical Properties Of Military Bridge Section Based On Tensairity Structure

Tensairity structure is a new structure system with light weight, small transport size, fast constructing and strong bearing capacity, which is composed of inflated airbags with low internal pressure, flexible cables and rigid compressed elements,. Based on the Tensairity structure, a solution of designing bridge sections is proposed in this paper and the mechanical properties in both unidirectional and bidirectional Tensairity structure are also investigated. The main contents and innovative work in this paper are as follows:(1) The Patran/Nastran finite element software is used to set up the finite element model of the Tensairity structure and to simulate the structure experiment of the unidirectional Tensairity beam numerically, which is found accord generally with the experiment, therefore, the feasibility and rationality of the numerical simulation methods of the present study are justified.(2) Based on the principles of Tensairity structure, the Tensairity structure bridge sections are preliminarily designed aimed at military use. A static analysis of the Tensairity structure under wheel and caterpillar loads is also made in this paper. Besides, by studying parameters such as the span rate, inflated internal pressure, section height of the upper chord and the diameter of the lower chord, the effects of these parameters on the deformation and internal force of the structure are summarized, which makes contributions to the Tensairity structure bridge project designs.(3) Developing unidirectional structure further to bidirectional and a preliminary design of the bidirectional structure is proposed. In addition, the mechanical responses of the structure under the conditions of initial state and loaded state were investigated with numerical simulation, the effect of the structural parameters such as internal pressure and the height of airbags on the mechanical properties of structure are analyzed, and the effect of the preliminary inflated internal pressure and the height of airbags on camber of the bridge surface and stress of aluminum alloy sandwich panel are primarily conducted.(4) The properties of the unidirectional and bidirectional Tensairity structure bridge section are compared. The results show that: Compared with the unidirectional Tensairity structure, the bidirectional one has relative larger rigidity and can bear bigger load under the same internal pressure.