Equilibrium Paths of a Fractional Order Viscoelastic Two-Member Truss

The fractional dynamics equation of a viscoelastic two-member truss system, in which fractional derivative model introduced to simulate the materials’ characteristics, is proposed. The equilibrium paths under vertical loads, horizontal loads and combined loads are discussed respectively. The results show that: there are primary and secondary equilibrium paths under vertical and horizontal loads. Bifurcations will occur under combined loads and the ultimate bearing capacity of the system will reduce. The equilibrium paths became complex because of the horizontal disturbance, and the bigger of the horizontal disturbance the smaller of the system ultimate bearing capacity.