Truss bolt & chord member bolt : truss bolt is used for connecting the upper and lower truss. While using, insert the bolt into the hole of truss chord member bolt from top to bottom, let the bending pad of the bolt seize inside the chord member, and tighten the nut. The chord member bolt, similar to the truss bolt, only 7cm in length, is used for connecting truss and reinforced chord member, installed according to Fig. 3-20, let the screw head bury into the reinforced chord member, avoiding blocking the bridge while pushing out.