Weather-resistance bridge high-strength steel plate and production method thereof

The invention discloses a weather-resistance bridge high-strength steel plate and a production method thereof. The weather-resistance bridge high-strength steel plate is prepared from the following components in percentage by weight: less than or equal to 0.11 percent of C, 0.30 to 0.50 percent of Si, 1.10 to 1.35 percent of Mn, less than or equal to 0.020 percent of P, less than or equal to 0.006 percent of S, 0.25 to 0.40 percent of Ni, 0.04 to 0.08 percent of V, 0.025 to 0.045 percent of Nb, 0.010 to 0.040 percent of Alt, 0.45 to 0.70 percent of Cr, 0.25 to 0.40 percent of Cu, 0.02 to 0.08 percent of Mo, 0.015 to 0.025 percent of Ti, less than or equal to 0.015 percent of N and the balance of Fe and inevitable impurities. The invention also relates to a production method of the weather-resistance bridge high-strength steel plate. The steel plate has excellent obdurability matching, high yield strength, high weather resistance and high cold-workability. The steel quality is purer, and the maximum thickness of the steel plate is up to 90 millimeters. The weather-resistance bridge high-strength steel plate is mainly used for manufacturing ocean platform and large sea-crossing bridge structural parts.