| Aluminum alloy is a new kind of material consisted of pure aluminum and alloying elements.The low elasticity modulus and density of aluminum alloy lead to the special seismic performance of aluminum alloy grid structure.Meanwhile,the skin effect of aluminum alloy grid structure is complex and the rigidity of aluminum joints is weak.The stability performance of aluminum alloy grid structure is unique.The stability of the aluminum alloy latticed shells were analyzed by ABAQUS,and the seismic performance of aluminum alloy grid structures were analyzed by Midas GEN.During stability analysis,over one hundred finite element models of both spherical shell and cylindrical shell were estabilshed.Over 1000 parametric finite element analysis with different initial imperfection,span,rise-span ratio,sectional dimension were established were studied.Meanwhile,the impact of stressed-skin effect of roof boarding was analyzed.Moreover,the rigidity of joints were considered in finite element models and the influences of joint semi-rigidity were investigated.During seismic performance analysis,dozens of grid structure and single-layer reticulated shell models with two load conditions and different geometric parameters were established.The structural material was setted as aluminum alloy and steel respectively.The natural vibration period,mode of vibration and stress of aluminum alloy structure and steel structure were compared by Midas GEN.Based on results of numerical simulation,the range of geometric parameters of both spherical shell and cylindrical shell were were analyzed,the influencing coecients of initial imperfection,material nonlinearity,stressed-skin effect and semirigid joint on stability bearing capacity were obtained.And the structural stability safety coecient and the approximate calculation formula were derived.The seismic performance checking standards of steel alloy space grid structure were conservative for aluminum alloy space grid structures. |
PDF Full Text Request