High-strength fastener for bridge in marine atmosphere and humid environments

The invention discloses a high-strength fastener for a bridge in marine atmosphere and humid environments. The high-strength fastener consists of a base body and a plating layer plated on the base body. The plating layer is a cathode compact composite plating layer which is of a three-layer structure, wherein the inner plating layer and the outer plating layer are made of nickel alloy or cobalt alloy, and the middle plating layer is a unit metal plating layer. The corrosion potential of the base body is smaller than that of the inner plating layer attached to the base body; the corrosion potential of the inner plating layer attached to the base body is smaller than that of the middle plating layer; and the corrosion potential of the plating layer of the outer plating layer is smaller than that of the middle plating layer. The tensile strength and the yield strength of the high-strength fastener range from 1000 Mpa to 1200 Mpa. The product is applied to bridge component connecting devices in marine atmosphere