Adhesive Lifting Scaffold Considering Protective Mesh Research On Bearing Capacity

Compared with the traditional round steel pipe scaffold,the attached lifting scaffold has great advantages in terms of construction efficiency,economic benefit and safety civilization,and gradually becomes an irreplaceable construction tool.However,due to the lack of depth in the study of attached lifting scaffold,many safety accidents caused by improper design or use have occurred,resulting in casualties and economic losses.Therefore,it is necessary to conduct more in-depth research on the mechanical properties of attached lifting scaffold under some adverse conditions.In the calculation of various mechanical performance indexes of attached lifting scaffold,the current specification does not consider the role of the protective net plate.However,the protective net plate densely distributed on the frame often uses large amount of steel,and its contribution to the bearing capacity of the frame is completely ignored,which will inevitably lead to the waste of steel.In order to effectively reduce the self-weight of the attached lifting scaffold and further improve its work efficiency,this paper considers the bearing effect of the protective mesh plate.Taking the sub-structure of the attached lifting scaffold as the research object,the monotonic static load is used to simulate the two common adverse conditions of the attached lifting scaffold.Through full-scale test and finite element simulation,the role of the protective mesh plate in the attached lifting scaffold is studied.The main research work includes:(1)Taking the 1 × 1 and 3 × 3 substructures of the attached lifting scaffold as the research object,the corresponding full-scale specimens were designed and manufactured.Three different connectors are used to simulate the test of the protection grid plate and the main frame under lateral load and vertical load.The specimen information,test material,test device,loading method and test data acquisition scheme are introduced in detail.Combined with the strain-loading displacement curves of each measuring point,the whole loading process of 11 specimens was described in detail,and the load-loading displacement curves of loading points were studied combined with the experimental phenomena.By analyzing the failure mode,ultimate bearing capacity and frame stiffness of each specimen,the bearing performance of each specimen under different connection forms was comprehensively evaluated,which provided a reference for the selection of connectors.Then,by analyzing the relationship between the deformation of key members and the loading displacement of the attached lifting scaffold under different loading conditions,the weak position of the scaffold is proved,which provides a reference for the structural design of the scaffold.(2)Using the finite element software ABAQUS,based on the test,the parametric analysis models of the wall thickness of the members of different protective panels,the form of the diagonal support of the main frame and the installation position of the connectors are established.The calculation results of the finite element model were compared with the failure mode of the test and the load-displacement curve of the loading point to verify the rationality of the finite element model.Through the discussion and analysis of the calculation results of the model,it is found that the wall thickness of the protective panel rod,the form of the inclined support of the main frame and the installation position of the connector will affect the bearing performance of the attached lifting scaffold,and the law of the parameters affecting the bearing performance of the frame is summarized,which provides theoretical support for the structural design of the frame.(3)The research content of this paper is summarized,and further research prospects are pointed out based on the shortcomings of this paper.