Research On Damage Feature Extraction Method Of Tower Crane Steel Structur

Because it works in high-risk outdoor places with heavy loads and large impacts all year round,the safe operation of tower cranes(hereinafter referred to as tower cranes)has always been the focus of management in the industry.As the main bearing structure of the tower crane,the tower body is one of the most prone to damage in the tower crane.If the damage cannot be identified early,the necessary reinforcement and repair will not be carried out.It is easy to cause safety accidents of tower crane collapse,resulting in property damage and casualties.Therefore,it can effectively extract the damage characteristics of the tower crane and carry out early identification,early monitoring,early prevention and early intervention of the damaged tower crane body,which is an important guarantee for the safe operation of the tower crane.Based on the established ADAMS model of the tower crane(which is based on the design parameters of the QTZ40 tower crane),different damage states are constructed to collect the top displacement trajectory of the tower crane body.The displacement trajectories of the top of the tower crane in the intact state and different damage states were analyzed,so as to obtain the characteristics of different damage states.Through the MATLAB GUI interface,a tower damage feature extraction and analysis system is established to extract and analyze the damage characteristics of the damage state.Its main contents are as follows:(1)A method for identifying tower damage was established and its feasibility was verified.Build 30 different damage types.The top displacement trajectories of the tower crane tower body with different damage states were collected,and the normalization and fitting of the sum of cubic chords were obtained to obtain the frequency,amplitude and phase of the X and Y directions of the top displacement trajectory.Then,the characteristic values of different damage states are obtained.Finally,the feature mapping plane is established.Any tower structure damage state corresponds to a point in the feature mapping plane.If the eigenvalues are in the safe area,the tower is in good condition.Otherwise,it means that the tower body of the tower crane has been damaged.(2)The diagnostic methods of different types of damage to the tower crane tower body were studied.Different injury types such as single main limb injury and adjacent main limb injury were constructed to obtain their apical displacement trajectories.The obtained top displacement trajectory is processed to obtain the eigenvalues of simulation data and experimental data.Subtract the eigenvalues of the simulation data from the eigenvalues of the experimental data to obtain the difference between the eigenvalues.The characteristic plane is established by taking the difference in the X direction as the abscissa and the difference in the Y direction as the ordinate.The closest approach method based on KNN(K Nearest Neighbors)is used to judge different damage types of different tower cranes.(3)The location of tower damage is located,and the development path of tower damage is diagnosed.The damage location of the tower body is diagnosed by studying the center of gravity of the top displacement trajectory of the tower crane and the external rectangular area of the top displacement trajectory.The development path of tower crane damage is analyzed by the change of eigenvalue.(4)The above work is visually modeled using the MATLAB GUI language.A tower damage feature extraction and analysis system was established.Through this system,the damage characteristics of the tower crane tower body can be extracted and analyzed effectively and conveniently.In summary,this paper proposes a method to analyze the displacement trajectory of the top of the tower crane and extract the damage characteristics.And the tower crane damage characteristics extraction and analysis system was established to diagnose,classify and locate the damage of the tower crane and tower body.