There are several methods to reinforce steel I-beams against seismic forces. One common method is using cross braces, which are diagonal steel members that connect the flanges of the I-beam, providing additional stiffness and resisting lateral forces. Another method is adding steel plates to the flanges and web of the I-beam, known as flange and web stiffeners, which increase the beam's resistance to bending and shearing. Additionally, steel channels or angles can be welded to the sides of the I-beam to enhance its strength and rigidity. These methods help to improve the overall performance and stability of steel I-beams during seismic events.
