Study On The Load Of The Preset Lifting Tower Foot And Foundation Of Power Transmission Tower In Mining Area

With the strategy of converting coal transmission to power transmission proposed, many transmission lines have to go through mining area inevitably. The surface subsidence in mining area can cause the towers to tilt, which seriously endangers the safety of transmission line. The existing rectification technology for tilted tower is complicated, requires large amount of equipment and high labor intensity. So it is significant and necessary to study rectification technology of simple operation and convenient construction.Taking the tower of 110 k V 1B-ZM3 type as the background, the tower foot is designed to be preset lifting structure, one kind of preset lifting structure system for mining area transmission tower is proposed, a planar full scale two-direction loading test device is developed. Considering the factors such as the thickness of the shoe board, the thickness of the base plate and the position of the stiffening rib, 7 tower foot members are made to simulate the ultimate bearing capacity. The variation law of ultimate bearing capacity and the destruction form of tower foot structure, strain distribution and plastic strain development of shoe plate and strain values in different regions of the tower foot base plate are obtained. These can provide reference for preset lifting tower foot structural design.The ANSYS analysis model of preset lifting tower foot is established,the differences between model test and numerical simulation are compared and analyzed. The results show the reliability of the numerical simulation results.By using ANSYS finite element software, the influence of the shoe plate thickness, the bottom plate thickness, the position of the stiffening rib and the height of the stiffening rib on the bearing capacity and ultimate bearing capacity of the tower is studied.Research results show that increasing boot plate thickness can improve the tower foot bearing capacity and deformation capacity, Increasing the thickness of the bottom plate can improve the bearing performance of the tower while reducing the deformation capacity, external displacement of stiffening rib or increasing the height of the stiffening rib can improve the bearing capacity and deformation capacity of tower foot.Taking the foundation of the tower of 110 k V 1B-ZM3 type as the research object, the foundation main column is designed to be a jack up structure. Considering four kinds of typical working conditions,normal use under axial compression and normal use of eccentric compression, jacking state under axial compression and jacking state under eccentric compressive, the bearing capacity of foundation main column is tested, the influence law of reserved loading groove, strengthen configuration stirrups, eccentric compression on bearing capacity and deformation form is analyzed,the calculation method of load bearing capacity of the foundation main column under normal use and jack up condition is proposed, which can provide reference for engineering design.