GROUT INJECTION METHOD INCLUDING PROCESS FOR DRAWING VACUUM FROM CABLE SHEATH OF POST-TENSION-TYPE PC STRUCTURE

摘要

A grout injection method including a process for drawing vacuum from a cable in a post-tension-type PC structure provides a cable in which a sheath is fully filled with grout without leaving any part not filled with the grout. In the grout injection method, including the vacuuming drawing process, for filling the sheath (3) with grout, to inject the grout into the cable sheath, a pressure pump (10) is connected to the grout injection side and a vacuum pump (20) is connected to the discharge side, the air pressure in the sheath (3) is reduced by the vacuum pump (20), and then the pressure pump (10) is operated to fill the sheath (3) with the grout. Prior to executing work in a construction site, a grout injection test apparatus having three-dimensional arrangement same as that in the construction site, except that the test apparatus has no concrete placing section, is assembled outside the construction site by using a cable having a sheath of a transparent material. A grout injection test is performed under different test conditions using the grout injection test apparatus, and a grout injection condition having the best result visually selected is applied to the construction site to execute construction.