Effect of Interfacial Contact Forces in ACSR Dog Conductor

Abstract

The mechanical behaviour of single layer cables used in engineering applications, have been studied for the past three decades and it varies widely depending on the numerical models adopted. Though these models predict the global response reasonably well, they differ widely in modelling the local contact conditions, the frictional effects at the interfaces and predicting the loss of stiffness of the single layer cable assemblies. The behaviour of the single layer cable can be well understood if the appropriate mode of contact prevalent at every stage of loading is adopted in the model. This paper analyses the contact modes present in a single layer cable assembly and considers its response under an axial tensile load and an axial twisting moment. Also this paper has formulated a sound theoretical model to find the response of a single layer cable considering all the interfacial forces in a coupled and radial contact mode and validate the experimental. Also proposes an arrangement to consider the axial and twist slip, by considering the tangential and the normal distributed forces at the contact interfaces. The effect of the friction and the associated slip of the wires have been included. Apart from consideration of the radial contraction of the wires due to the Poisson effect, as accounted by few authors, this paper considers the radial deformation due to contact forces, as a special feature. This has resulted in refined expressions for the curvatures and twist of the wire and the associated forces in the normal and binormal directions. The predictions with these inclusions are compared with the existing works and the importance of the refinements to the cable designers is highlighted.