Study On Impact Resistance Of Single-Layer Reticulated Shell

The long span structure have been got a good development and application because of its beautiful shape and reasonable stress system. As a main sort of long span structure, the reticulated shell structure was widely used in exhibition centre, terminal, theater, storage structure and other important engineering.Although the impact load belong to accidental load, the probability of impact on bulidings is increasing due to the natural disasters, the terrorist attacks and the increasing number of aircrafts with development of science and technology. The impact resistance of buliding structure is attracted much attenetion due to the911event.A light aircraft crashed into the truss roof of Sao Paulo Exhibition Center in1980s, it is demonstrated that the possibility of long span structure destroyed under the impact load.In order to reduce the losses caused by impact load, ANASYS/LSDYNA and impact test was used to research the dynamic response and impact resistence of single-layer reticulated shell under the impact load. The main contents show as follow:1. The basic theory of the research to single-layer reticulated shell impact resistence was introduced, including dynamic buckling criterion, geometric large deformation effect, constitutive equation of strain rate, dynamic analysis method, etc. Then, the analytic procedure of ANSYS/LS-DYNA, including explicit method, explicit elements, dynamic contact algorithm and material model were introduced, and the K6single-layer reticulated shell with60m span was created.2. The concept of critical impact kinetic energy was defined based on B-R motion criterion. Studing the impact response rule and dynamic property. Four typic impact response modes were defined according to the final deformation and failure modes of reticulated shell under the impact load.3. The influence of properties of material and cross section to impact resistence were studied by parametric analyses.4. An impact test of a K6single-layer reticulated shell with3m span was used to research the impact response characters. Then, the contrast between test and FEM were used to improve the correctness of FEM.