Research On Layout And Spacing Of Scaffold Tie Member

As our country's economic development enters a new normal,the transformation of the construction industry and the improvement of people's aesthetic make the urban architecture develop towards diversification and individuation.With the continuous emergence of high-rise and super high-rise buildings as well as buildings with unrestrained appearance and novel shapes,construction scaffolding has become an indispensable temporary framework in the construction process.The erection of scaffold is restricted by its architectural structure shape.No matter from the perspective of building height or structural complexity,it puts forward higher requirements for the safe use of scaffold.As the key member connecting the frame and the main structure of the building,the reasonable design of tie member plays an important role in the construction safety.Therefore,it is of great significance to study the safety of layout and spacing of tie member in construction.Considering the semi-rigidity of the joints,taking the double pole steel tube scaffold with couplers as the research object,using the finite element software ANSYS,this paper studies a series of problems such as the influence of the parameters such as the different layout and the different arrangement spacing on the axial force and stress of tie members and the internal force of other members of the scaffold,the stability bearing capacity of scaffold and the lateral rigidity of scaffold.This paper analyzes the force characteristics of scaffold with couplers and makes assumptions.According to the three calculation theories,the node semi-rigid calculation model,the node rigid connection calculation model and the node articulation calculation model are respectively established,and the most reasonable calculation model is selected by comparison with the previous experimental data.Through the analysis of the wind load action of scaffold,the influence of wind vibration is taken into account in the calculation of the horizontal wind load action on scaffold,and the wind load standard value at different heights from the ground is calculated.The finite element analysis is carried out on the force of tie member of the frame under the rectangular and rhombus layout,and the axial force and stress of the finite element analysis are compared with code calculated values,it is found that the calculation formula of the current scaffold code for tie member is not enough to reflect the real stress of tie member in the construction of high-rise and super high-rise buildings.In order to consider the safety design and use,it is suggested to adjust the reduction coefficient of the strength design value of the standard calculation formula for tie member in the construction of high-rise and super high-rise buildings and the adjusted reduction coefficient is given.The semi-rigid joint finite element analysis is carried out for the mechanical performance of the frame under three kinds of layout modes of tie member,and the influence degree of the three layout modes on the internal force,stability bearing capacity and lateral stiffness of the frame is compared.It is found that the stability bearing capacity and lateral stiffness of the frame are increased by 60% and 28% respectively when tie member is arranged in diamond along the direction of upright tube compared with the rectangular layout.It shows that the diamond layout of tie member along the direction of upright tube is more favorable for the safety performance of the frame.In addition,the paper studies the different spacing of tie member under the optimal arrangement of tie member in diamond layout and common rectangular layout and analyzes the reasonable spacing of tie member.Under different layout,the limitation requirements for the reasonable spacing of tie member at different heights of the frame are given,hoping to provide reference for the safety design of tie member.