| China’s high-speed railway construction has made rapid development in the past ten years,has the world’s largest and fastest high-speed railway network.However,the accident frequency of derailment hitting composite structural columns increases,resulting in serious casualties and economic losses.It is particularly important to improve the anti-collision ability of composite structural columns.Therefore,this paper proposes a new energy dissipation anti-collision composite structural column with replaceable X-type energy dissipation device,which can effectively consume the huge impact energy generated by the lateral impact of the train,thus reducing the damage to the station column.Therefore,it is of great scientific significance and engineering application value to study the crashworthiness and working mechanism of energy dissipation and collision reduction station column.In this paper,the mechanical properties of the new energy dissipation anti-collision composite structural column are analyzed through the drop hammer impact test and numerical simulation.The main research contents are as follows:(1)Lateral impact test of replaceable X-type energy dissipation device was carried out on DHR9401 drop hammer impact test platform of Structure Laboratory of Taiyuan University of Technology to optimize the size design of X-type energy dissipation device.Taking height weakening parameter a,length weakening parameter b and height-span ratio c as test parameters,the deformation process,final failure mode,impact force time history curve and displacement time history curve of the damper were obtained.The analysis results show that with the increase of the weakening parameters a,b and c,the energy dissipation capacity of the specimen gradually increases.(2)The finite element model of X-type energy dissipation device under impact was established,and the reliability of the finite element model was verified based on the test data.Based on the verification model,the working mechanism of the X-type energy dissipation device under impact was analyzed.Based on the results of failure pattern,effective plastic strain and energy analysis,the influence of weakening parameters a,b and c on the energy dissipation performance of the X-type energy dissipation device was deeply understood,and the optimal specimen size of the X-type energy dissipation device was obtained.(3)The finite element model of new energy dissipation anti-collision composite structural column under impact load is established.Firstly,the reliability of finite element simulation is verified based on typical test data.Then,the whole process analysis,failure mode analysis,effective plastic strain analysis and impact energy analysis are carried out on the new energy dissipation anti-collision composite structural column,and the energy dissipation effect and the protection of the station column are generally understood.Finally,the influence of the thickness and arrangement of the X-type energy dissipation device on the new energy dissipation anticollision structural column is studied and analyzed.(4)The finite element model of a new energy dissipation anti-collision composite structural column filled with aluminum foam is established.Under the condition of ensuring the reliability of the finite element model,the failure pattern analysis,impact time history curve analysis,displacement time history curve analysis and impact energy analysis were carried out.Finally,different aluminum foam density was adopted to study the influence of aluminum foam density on the new type of energy dissipation and anti-collision composite structural column. |
