The bi prestress concrete beam is prestress concrete beam spontaneous strike adopting tension prestress steel bar and precompressed prestress steel bar at one time to establish prestress on the section of the beam. 双预应力混凝土梁是同时采用张拉预应力钢筋和预压预应力钢筋而在梁截面上建立预应力的预应力混凝土梁。