Numerical simulation of 'thermal-mechanical' coupling of underground cable ducts

Abstract

Underground buried cables can improve the efficiency of power transmission and utilizing in the urban underground space. The current load capacity is an important parameter in cable design and operation. When the cables are concentrated in the concrete ducts, the mutual heating increases the temperature of the central cable. concrete pipe laying cable is a commonly used method for high voltage cable because of its high reliability, easy maintenance and convenient replacement. In given concrete duct cross sections and corresponding cable arrangements, the finite element method was used to analyze the temperature field distribution of concrete ducts section with different cable arrangements. The influence of buried depth of concrete duct and thermal conductivity of soil on cable current carrying capacity were discussed. Based on the temperature distribution of concrete pipe, the 'thermal-mechanical' coupling model of cable pipe was established by finite element method, and the distribution characteristics of temperature stress and strain were obtained. The research can provide scientific advice for the conduit’s arrangement and structural form optimization of concrete cable ducts.