Mechanical Properties Research Of The Hanging Steel-wood-plastic-composite Single-layer Reticulated Spherical Shell

Wood-Plastic Composite(WPC)materials are used to design the structure and connection of the hanging Steel-Wood-Plastic-Composite(SWPC)single-layer spherical reticulated shell,based on the actual engineering project.The internal force,deformation,and stability of SWPC reticulated shell under static load are analyzed,and the necessary research concerned with the SWPC reticulated shell has been carried out in many aspects.The first step in this process was to carry out the compression test and the bending test on WPC rods,then the failure form,ultimate stress,and ultimate strain were obtained.Secondly,the embedded SWPC joints designed and applied in this paper was simulated by using the finite element analysis software ABAQUS,studied the effects of different bolts rows,bolt diameter,bolt number,the distance between bolt group center and joint center,and the length of ear-board on the bending property of the SWPC joint.Following the research,the static load test was carried out taking two-span of the SWPC reticulated shells which are near the hanging joints,which was studied the force characteristics and failure modes.The final stage of study on the SWPC reticulated shells comprised the buckling analysis and the nonlinear stability analysis considering geometric defects by using Midas Gen,and the effects of the diameter of the SWPC reticulated shell,the effects of the size of the member section,the boundary conditions,the distribution of live loads and the stiffness of the joints on the stability were studied.This study has shown that the hanging SWPC single-layer spherical reticulated shell can meet the requirements of use under static load.The ultimate stress and elastic modulus of the WPC material are 21 MPa and 2100 MPa,and the failure of the test specimen shows brittle failure.For embedded SWPC joints,using double-row bolts instead of single-row bolts,increasing the diameter of bolts,increasing the number of bolts,increasing the distance between the center of bolts group and the center of joints,increasing the length of the ear-board is beneficial to improving the flexural behavior of the joints.There are three kinds of failure modes of the embedded SWPC joints,the bolt holes of the WPC beam are damaged by shear or compression,the web and upper flange are torn,the WPC beam is damaged by bending.When designing the SWPC reticulated shell,measures can be taken to strengthen the joints with large forces such as hanging points.In the process of building the SWPC reticulated shell,the possibility of generating virtual displacement should be reduced and the contact between the end of the rod and the joint ring should be avoided.The stability of hanging SWPC single-layer spherical reticulated shells increases with the decrease of reticulated shell diameter,the increase of members section size,and the increase of joint stiffness.Meanwhile,the reticulated shells with uniform hanging point distribution,small total live load,and only distributed in the upper or lower hemisphere have better stability.This study innovatively set out to the hanging SWPC single-layer spherical reticulated shell,whose main material is WPC.And proposes a method of connection,which is embedded SWPC joints.A series of research on the SWPC reticulated shell were conducted.These results,which are of great significance to the development of WPC structures,add to the rapidly expanding field of WPC applied in architectural engineering,lay the groundwork for future research and design into the hanging SWPC single-layer spherical reticulated shell.