Analysis of Large-Sag Extensible Catenary with Free Horizontal Sliding at One End by Variational Approach

A variational approach for the static equilibrium configuration analysis of a large-sag extensible catenary with free horizontal sliding at one end is developed, considering the virtual work done by the catenary self-weight and the horizontal tension at the free sliding end support. The virtual work of the cable system is expressed in terms of the vertical coordinate, which is a function of the unstrained arc length of the cable. The stationary condition is applied to the virtual work functional to obtain the equilibrium configuration of the catenary. The validity of the variational approach is ensured by Euler’s equation, which is identical to the one derived by the force equilibrium consideration of a catenary segment. The finite element method is used to evaluate the numerical results. A parametric study is performed to demonstrate the effect of axial deformation on the equilibrium configuration of a large-sag extensible free horizontal sliding catenary. The results indicate that as the axial deformation increases, the total arc-length and horizontal span length of the cable also increase. Particularly, the very large-sag catenary configurations are studied and exhibited in this study.

A Study for the Fatigue Failure Mode Assessment of Fillet Weldments

In this study, a methodology for the assessment of fatigue failure modes of weldments due to partial penetration weld has been carried out by using structural stress method. Structural stress calculation procedure, using shell element based on equilibrium consideration using nodal forces and moments, is employed. It is important to note that the structural stress calculation procedures for partial penetration welds can be used to determine a minimum weld leg length, beyond which, weld root failure modes can be effectively suppressed. An example study, with respect to a fillet weld leg length design, is compared with a design criterion, and they are found to be in agreement.