Study On Dynamic Response And Protective Measures For Kiewitt8Single-layer Reticulated Shell Subjected To Blast Loading

A series of terrorist bombing such as "9.11" and explosion accidentcaused by illegal operations had rung the alarm bell of buildings’ securityperformance, putting forward higher bearing capacity to resist explosion forstructure. Long-span spatial structure often plays an important role in the city publicarchitecture for its beautiful architectural shape and excellent mechanicsperformance, however, only a few studies have focused on long-pan spatialstructure subjected to blast loading. Clearly, there is a need of researches ondynamic response and protective measures for long-span spatial structure underblast loading in order to provide important support on blast resistance and defensefor practical engineering.Firstly, by using finite element software ANSYS/LS-DYNA, the simulation ofblast wave propagation was presented in air, By way of comparing the simulativeand experiential values from several references about the peak overpressure of blast,the mesh generation, mesh dimension, and selections of material parameters wereanalyzed in this thesis, which verified the accuracy and reliability of numericalsimulation effectively.A fine kewitt8single-layer reticulated shell model, including reticulated shellmember, purlin hanger, purlin, rivet, roof panel, wall and ground was established.The dynamic response of structure subjected to internal eccentric blast loading withdifferent TNT equivalent weight, explosion point position, section size ofreticulated shell member, rise-span ratio, supporting condition, thickness of roofpanel and roof load were studied by using ALE (Arbitrary-Lagrange-Euler)algorithm. The results showed that there are four dynamic response types forreticulated shell subjected to internal eccentric blast loading, which are NoImpairment, Member Developing Plasticity, Large Deformation of Reticulated Shelland Destruction with Explosion Relief.The dynamic response of structure with varied TNT equivalent weight,explosion point position, the member section size of reticulated shell, rise-span ratio,supporting condition, thickness of roof panel, roof load and the form of roof panel,subjected to external blast loading also has been investigated. Four dynamicresponse types of structure subjected to external blast loading were defined: NoImpairment, Local Deformation, Local Damage and Integer Collapse.Finally, the venting regulation of openings in the wall was concluded throughthe analysis of factors like the varied opening rates, opening numbers and positionsfor reticulated shell under internal blast. On the basis of the dynamic response of reticulated shell subjected to the internal and external blast loading, theinitiatory protective strengthening methods and blast resistant design were proposed.