Research on influence of initial curvature of members on elasto-plastic stability of reticulated shells

To investigate the influence of initial curvature of members on the elasto-plastic stability of single-layer reticulated shell structures, the multi-beam method was adopted to model the initial curvature of members, and based on the FEA package ANSYS, two methods were proposed to introduce the initial curvature of members of reticulated shells. According to the randomness of initial curvature of members, the random imperfection mode method was presented. Taking a Kiewitt-8 dome as an example explained the simulation process of the random imperfection mode method, and investigate the influence of direction angle and amplitude random variables of initial curvature of members on the stability of the reticulated shell structure. From the result of the random imperfection mode method, the modified consistent imperfection mode method was established. Then, based on this method, the stability of the Kiewitt-6, Kiewitt-8 and geodesic single-layer reticulated shells considering the influence of initial curvature of members were analyzed. For the structure without and with nodes deviation, the influences of initial curvature of members on the bearing capacity of the structures were obtained quantitatively. The results show that, for the structure without and with nodes deviation, the initial curvature of members can decrease the bearing capacity of the structure obviously, and change the degree of plasticity development of the structure. The influence of initial curvature of members on the elasto-plastic stability of single-layer reticulated shells cannot be neglected, and the modified consistent imperfection mode method is effective to estimate the lower bearing capacity of the reticulated shell structures considering the influence of initial curvature of members.