The behaviour of the power transmission tower subjected to horizontal support’s movements

Abstract

In this paper, two half-scaled test tower models for a typical 110 kV single-circuit power transmission tower were designed and fabricated. The scaled test tower models were tested under the horizontal support's stretching (tensile) and compressive movements with the normal working loading conditions. The deformations of the tested tower models and stresses within the different bracing members were fully measured. A large amount of comprehensive test data was generated. Also a finite element (FE) model using software ANSYS was developed and validated by the test data. The research indicated that the designed half-scaled test tower model can reasonably represent the behaviour of the whole transmission tower under the horizontal support's movements. The magnitude of the stresses was reduced from the bracing members at lower part to the bracing members at higher part of the tower. The effect of the ground surface deformations is more significant on the truss members closed to the supports. Hence, for the design of transmission tower against the horizontal support's movements, it is important to reduce the slenderness of those bracing members.Keywords：Power transmission tower; horizontal support's movements; scaled test tower model; FE analysis.  Develop a FE model using ANSYS for modelling the 110 kV power transmission tower.3

Experimental study on the stability of the transmission tower with hybrid slab foundation

“…According to the test results presented by Yuan et al [19] and current research the displacements of the supports A and D within the fixed box are very small and can be neglected. Therefore, here only the displacements of the supports B and C within the movable box are considered for the comparison (see Fig.…”

“…Therefore the shift in tower center of gravity due to horizontal ground movement was negligible under only vertical loading conditions. This has been proved by previous test [19]. The more feasible way to investigate the behaviour of transmission tower under real loading conditions is to use FE analysis which needs to be validated under more simple loading conditions by using available test data.…”

“…However, the displacements of the supports B and C with the isolated foundation used by Yuan et al [19] are linearly increased with the loading displacement. It can be seen that for the case with isolated foundation the displacements of the supports B and C are almost to equal the loading displacement.…”

“…Based on the current laboratory conditions it is very difficult and complex to simulate a real ground movement for a full scaled original tower. Previous research [19] indicated that most significant impact on the behaviour of the tower is the ground horizontal movement. Hence, this research focused on this kind of ground movement conditions.…”

“…Yuan et al [19] have conducted a test on the transmission tower with isolated leg's foundation subjected to ground movements. In order to assess the ground deformation resistance for different type foundations the results generated from that research are used to compare the test data obtained from this research.…”