The invention discloses a production method for producing an ultra-thick high-strength building steel plate with excellent thickness direction performance on the basis of a single
continuous casting rack. The steel plate is simple in component design and mainly uses cheap Ti, Cu and a proper amount of Nb
alloy as main strengthening
alloy elements. In the production method, the addition ratio of Si, Mn to Cu in the steel plate and the content of harmful elements P, S and P+S are mainly controlled in a
smelting process, so that the generation of the gas content, inclusions, shrinkage cavities and other defects in a
casting blank is reduced; by controlling rolling, the coarse columnar
crystal structure of the
casting blank is crushed,
crystal grains are refined, the fine and uniform structurein the thickness direction is ensured, and the strength is improved at the same time. Through controlling heat treatment, the structure defects are further eliminated, the structure is improved, thecomponents are homogenized, the
crystal grains are refined to obtain good thickness direction performance, and meanwhile, it is ensured that the strength meets the requirements. The method has the advantages of low production cost, high product performance and high added value, improves the production efficiency and
economic benefits, and has great popularization significance.