The stress state analysis of lattice tower support for 330 kV overhead line using the “USL” software package

Abstract

In conditions of market economy, overhead power transmission line (OPTL) support structures must be low-cost and of guaranteed quality, the manufacture of which will require a minimum amount of steel. Therefore, it is necessary to improve overhead line supports, which is possible by clarifying the forces in the support elements and when designing using numerical methods. In this article, a mode of deformation of a corner dead-end support of OPTL is analysed, which is considered a spatially multiple indeterminate open system with flexible joints. Attention is given to the basic problems that can occur in setting initial parameters and constructing design models for such structures. There are a number of problems connected with a refined specification of internal longitudinal stresses in the components of an OPTL structure. In designing, the joint operation of the lattice components of the support spatial pattern model is analysed, and the inclusion of stiffening diaphragms and diagonal element members in the operation on all four faces is taken into account. On the basis of the design and the extension of the results, the internal forces obtained and the ones specified in the components of the pattern OPTL support on the similar values of loads were thoroughly compared. When calculating the spatial model of an anchor-corner support as a result of the joint work of lattice elements, a decrease in internal forces in the elements of the spatial model is observed on average by 6.8%, compared to the forces determined in a typical overhead line support from the same load values. It has been established that it is quite acceptable to calculate overhead line lattice structures in the USL software package since the error in determining the forces in the rods is within 2% and the computer time consumption is less than in other software packages.