Numerical and Theoretical Analysis on Lateral Constrain Stiffness of Angle Steel with In‐Situ Nondestructive Reinforcement

Abstract This paper presents a new in‐situ bonded reinforcement technique to increase the lateral constraint stiffness of angle steel in transmission towers. The reinforcement method does not require drilling on the original material, making it easy to implement. Three sets of specimens with different reinforcement lengths and axial tension and one set of contrasting specimens were designed, and numerical simulations of the lateral constraint stiffness were carried out based on the tests to investigate the effects of reinforcement length and aspect ratio on the reinforcement effect. Finally, the calculation method of lateral constraint stiffness is proposed based on the approximate differential equation of the bending curve. The results show that the new nondestructive reinforcement technique significantly improves the lateral constraint stiffness of the angles by up to 63%. The reinforcement effect is negatively correlated with the axial tension, positively correlated with the reinforcement length, and negatively correlated with the aspect ratio. The proposed calculation method provides a theoretical basis and technical reference for designing and applying angle steel reinforcement.