Research On The Failure Mechanism For Single Layer Ellipsoid Reticulated Shell Structure Under Internal Explosion

In recent years, a number of deliberate or accidental explosions have occurred in public places. Large space structure is a conventional public buildings currently, therefore, the research of anti-explosion performance and failure mechanism for large space structure is very important.According to single layer ellipsoid reticulated shell structure as the research object, using ANSYS/LS-DYNA finite element software to simulate the explosion and response of structure, put forward the failure mechanism.The main contents and results in this paper are shown as following.(1) A simulation about explosion in unlimited free air has taken, compared the numerical simulation data of peak pressure, pressure time with empirical formula, verify the credibility of models of explosion. Also verifies the feasibility of explosives modeling by initial volume fraction, make the modeling independent with air element size.(2) Basing on free air explosive finite element model, the whole process of explosion in single layer ellipsoid reticulated shell structure is simulated and the internal explosion shock wave propagation is studied. Then, a parameter analysis for the response of single layer ellipsoid reticulated shell is carried out, by changing the rise span ratio, member section moment of inertia,connect stiffness, the quality and placement of explosives.(3) Studied the follow-up response of structure and these response patterns are classified as: minor injury, structural damage, collapse. Basing on energy-time curve, discussed the transfer relationship of the potential energy,strain energy, kinetic energy. Then the failure mechanism is proposed.(4) Basing on the research result in this paper, give some design suggestion of anti-explosion for single layer ellipsoid reticulated shell.