When a bridge twists due to wind or uneven loads what are the forces act on the bridge materials?

When a bridge twists due to wind or uneven loads, it experiences torsional forces that create shear stress in the materials. These forces can lead to bending moments, resulting in flexural stress across the bridge's structural members. Additionally, the uneven distribution of loads can induce axial forces, which can either compress or tension the materials, further impacting the bridge's stability and integrity. Overall, these forces must be carefully analyzed in the design to ensure the bridge can withstand such conditions.