Study on Progressive Collapse Performance of Aluminum Alloy Honeycomb Plate Composite Reticulated Shell Under Strong Earthquake

In order to improve the computational efficiency of the aluminum alloy honeycomb plate composite reticulated shell,the finite element analysis model was established by using the coupling method (contact model) and the complete coordination method.The finite element analysis results were compared with the bearing capacity test results of the aluminum alloy honeycomb plate composite reticulated shell.Based on the two types of finite element analysis methods,the large-span aluminum alloy honeycomb plate composite reticulated shell model was established,and the complete coordination method with the reduction coefficient was proposed as the simplified calculation method of the aluminum alloy honeycomb plate composite reticulated shell.Based on the above simplified calculation method,the finite element analysis model is established,and the variation of natural frequency of aluminum alloy honeycomb plate composite reticulated shell under different rise-span ratios (1/4,1/5,1/6),different spans (40,50,60 m) and different plate thicknesses (5,10,15 mm) was studied by ANSYS software.The time-history analysis of aluminum alloy honeycomb plate composite reticulated shell were carried out.The dynamic displacement response of the structure and the proportion of the members entering the plasticity were comprehensively studied and the acceleration amplitude of the reticulated shell was obtained when it was destroyed.The influence of different rise-span ratios,different spans and different plate thicknesses on the progressive collapse resistance of aluminum alloy honeycomb plate composite reticulated shell under strong earthquake was discussed.The results show that when the plate thickness is reduced by 20%,the error between the finite element analysis results and the experimental results is 5.87%,and the error is within a reasonable range.The complete coordination method with a reduction factor of 0.8 was proposed as a simplified calculation method for aluminum alloy honeycomb composite reticulated shells,and it is applied to the natural frequency analysis of composite reticulated shells and the progressive of composite reticulated shells under strong earthquakes.Through the modal analysis of the composite reticulated shell,it is found that the natural frequency of the composite reticulated shell increases slightly with the increase of the order.The decrease of the rise-span ratio will cause the decrease of the natural frequency of the composite reticulated shell.The decrease of span and the increase of plate thickness will increase the natural frequency of the composite reticulated shell.Through the time-history analysis of the composite reticulated shell,it is found that with the continuous increase of the acceleration amplitude,the maximum displacement of joint and the proportion of members entering the plasticity of the aluminum alloy honeycomb plate composite reticulated shell with different rise-span ratio,different span and different plate thickness are gradually increasing.When the acceleration amplitude is 325 m/s²,375 m/s² and 400 m/s²,the composite reticulated shell with rise-span ratio of 1/4,1/5,and 1/6 successively collapses under the action of El Centro wave.When the acceleration amplitude is 300 m/s² and 350 m/s²,the composite reticulated shells with spans of 40 m and 50 m successively collapse under the action of El Centro wave.When the acceleration amplitude is 225 m/s² and 575 m/s²,the composite reticulated shell with plate thickness of 5 mm and 15 mm successively collapses under the action of El Centro wave.The decrease of rise-span ratio,the increase of span and the increase of plate thickness will increase the acceleration amplitude of the composite reticulated shell under the action of El Centro wave,which further confirms the improvement of the progressive collapse resistance of the aluminum alloy honeycomb plate composite reticulated shell.