Method of forming a composite structural member

A method for constructing a bridge, said method comprising the steps of:

• preparing a plurality of concrete slabs each having buried therein a plurality of sheath tubes extending parallel with each other, said preparing comprising forming each said slab with undulated end surfaces at opposite ends thereof;
• arranging a pair of abutments in spaced relationship with each other;
• placing a plurality of main beams in parallel with each other on and extending between said pair of abutments;
• disposing said concrete slabs across said main beams such that said slabs are juxtaposed to extend across said beams and that said sheath tubes in said slabs extend parallel with the longitudinal direction of said beams, said disposing said slabs comprising positioning said slabs on and across said main beams at specified intervals such that said undulated end surfaces of said slabs face one another on said beams;
• inserting pc steel wires into said sheath tubes in said slabs;
• then producing in said slabs compressive stress acting in a direction parallel with said longitudinal direction of said main beams by applying tension to said pc steel wires by means of stretching means;
• fixing said compressive stress to said slabs by means of fixing means;
• fixedly securing said concrete slabs on said main beams to thereby integrate said slabs and beams, said securing comprising positioning dowels fixed to said main beams in spaces defined between the thus confronting undulated end surfaces and filling said spaces with mortar, thereby integrally securing said slabs to said beams;
• and
• thereafter actuating said fixing means to adjustingly release said compressive stress acting in said slabs thereby producing in said beams a tensile force acting in said longitudinal direction of said beams and a negative bending moment acting upwardly.