| The rapid development of the power industry in recent years has led to an increase in the load borne by the transmission tower.The increase in load has made whether the bearing capacity of the foundation column can meet the requirements and whether the tower foot plate can meet the strength has become a hotly debated issue.Concrete often appears in actual projects.Cracking and failure and failure of the tower foot plate being pulled out.This is very important to ensure the safe operation of the life project of this transmission line.Based on the actual electric power institute project,this paper will conduct mechanical analysis of the tower foot plate and foundation column,simulate the reinforcement measures of the foundation column,and optimize the structure of the square tower foot plate.The main research content and research results are as follows:1.By introducing the concrete damage model to simulate the reinforcement measures of the concrete column,it is found that in the elastic stage,whether to add steel mesh will not change the internal stress field of the concrete,and the steel mesh will restrain the concrete in the plastic stage.Reinforced mesh can well restrain the lateral deformation of concrete,reduce the damage of concrete,and indirectly increase the ultimate bearing capacity of concrete.2.Exploring the reasonable arrangement height of the steel mesh,which is to meet the bearing capacity without causing waste of steel,simulate the steel mesh with different mesh layout heights,and obtain the internal mesh of the foundation column under the action of the circular tower foot.The layout height when the diameter-towidth ratio d/b is less than 0.5,the layout height only needs to double the section width,and when the ratio of the outer diameter of the circular tower foot to the section width d/b is between 0.5 and 1,the layout height of the steel mesh 1.5 times the section height is sufficient,and when the double-angle steel square eight-foot pylon foot plate is compressed,because the local pressure surface is small,the mesh arrangement height can be doubled the section height.The longitudinal spacing of the mesh should be80 mm.80mm is the optimal spacing when considering the bearing capacity and damage.The horizontal layout of the mesh should be arranged in a small and dense manner.Different concrete strength grades have a certain influence on the concrete bearing capacity.3.Use the Ritz method to fit the stress expression of the nonlinear contact between the square tower foot plate and the foundation column,which provides a theoretical basis for the square tower foot plate under compression.At the same time,considering the thicker thickness of the traditional square tower foot plate,in order to reduce its weight,the structure of the stiffening plate was explored,and the appropriate stiffening plate layout was found.The stiffening plate was changed while the maximum bending stress was the same.The arrangement form can achieve the effect of reducing the thickness by 10%,and the arrangement form of the stiffener only needs to exceed the edge of the anchor bolt in length,and the closer the stiffener is to the anchor bolt,the smaller the bending stress,the thicker and higher the stiffener The smaller the bending stress,the position of the bolt hole should be as close to the shoe plate as possible in consideration of the construction conditions and the local tensile strength of the concrete. |
