Method for manufacturing prestressed steel box concrete beam through pre-tensioning method

The invention relates to a method for manufacturing a prestressed steel box concrete beam through a pre-tensioning method. The method includes the following steps that a box body is manufactured, an upper flange board, a lower flange board and two webs are welded into the box body, and two end sealing boards are welded; multiple prestressed steel strands penetrate into the box body, and two tensioning boards are arranged at the two ends of the box body; the prestressed steel strands are tensioned, and the two ends of each prestressed steel strand are fixed to the two tensioning boards; concrete is poured; the prestressed steel strands are released; and the prestressed steel strands are cut off, the tensioning boards are detached, and the steel box concrete beam is manufactured. By the adoption of the method for manufacturing the prestressed steel box concrete beam, the use amount of a concrete material is small, energy is saved, environment friendliness is achieved, and the bearing capacity, the rigidity, the