Study On Mechanical Properties Of Multi-Branch Pipe Joints In Sail Shaped Framework

Substation framework is one of the most important buildings in substation.The steel pipe structure is the main structural form of the frame because of its superior comprehensive performance.The steel joint is the key component of this kind of frame structure.Its design form and bearing capacity play a decisive role in the overall structural safety of framework.It is often used to construct the traditional framework joint in simple form.However,the traditional substation framework has the disadvantage of occupying a large area.This requires the design of a new type of framework to reduce the area occupied.The difficulty in the design of a new type of structure lies in the complexity of its construction form,while the conventional joint form is difficult to meet the structural requirements.Therefore,it is of great practical significance to study new type composite joints.The space multi-branch pipe joint of the sail shaped joint outlet frame is a new type of composite joint,which has the characteristics of intersecting joint and board joint.In this paper,a new type of joint structure is designed based on the engineering background.The mechanical properties of the frame joints are studied from two aspects of full-scale model test and numerical simulation.In the full-scale model test,the layout of test points,loading scheme and data acquisition scheme are introduced in detail.In order to study the stress level and development trend of joints under different loading conditions,the test results show that the stress levels of the joints are lower and all of them are in the elastic range.And there is no obvious deformation in the loading process.On the basis of the experiment,the joint is modeled by Abaqus finite element software,and the finite element numerical simulation analysis is carried out strictly according to the loading system of the test,and the numerical simulation results of the node are obtained.The results of finite element calculation and test are compared and analyzed.The results show that the joint test results and the finite element results have a high degree of agreement,and meet the requirements of the strength and stiffness of the engineering design.And there is sufficient safety reserve.Therefore,under the premise of ensuring the strength of the joint,the thickness of the gusset plates and stiffened ribbed plate is taken as the design variable,and the light weight optimization design of the joint is carried out in order to save the manufacturing cost.As a new type of composite joint,the space multi-branch pipe joint of the sail shaped framework is reasonable in design and superior in mechanical performance.The optimization results of the joint can provide a reference for the design of the new type substation framework joint.