Effects of Different Initial Imperfections including Residual Stress on the Compressive Bearing Capacity of Steel Angles in Towers

Angles are extensively used in latticed transmission tower. Initial imperfections have a significant impact on the compressive instability and failure of angle components. To study the impact of different initial imperfections on the compressive bearing capacity, general-purpose finite element software ANSYS is used. With shell element SHELL181, selecting angle L200×20 of the slenderness ratio of 20, 40, 60, 80, 100 and 120, the bearing performance analysis with initial imperfections is conducted, including initial bending, section defects, initial eccentricity, residual stress, and a combination of imperfections. At the same time, for the angle components of the optimal slenderness ratio of 40 and slenderness ratio of 80, under the single influence of initial bending, section defects and residual stress, how the size of the value of the imperfections affects the bearing performance is investigated.