Effectiveness of pressurized filling of lining concrete forimproving the quality of tunnel crown
Generally, the compacting for the crown of concrete lining in tunnel depends onhuman power within electrical vibrators reach from the inspection windows. Confirmation whetherwe are able to fill up the space for lining or not demands much of visual judgment and experiences.In JAPAN, now we always use the pulling vibrator and judge if filling up or not with the detectedsensor in “Mt. Nosakadake Tunnel” on the Maizuru-Wakasa expressway. In recent years, inconstruction of the tunnel lining concrete, it is mainstream for certain filling and the safety for theformwork to manage the filling pressure. And so, toward the higher quality of concrete lining intunnel we plan the operating method of pressing and filling up the space with the pressure sensor. Atfirst we confirmed the relation of increasing rate of compressive strength and adding pressure inlaboratory experiment. Secondary we confirmed the relation of filling pressure distribution forconcrete and the quality of concrete what is called “the strength of surface” and “air permeability”.Finally, we examined the measuring with the sensor of compacting concrete to evaluate thecompacting degrees of concrete lining in tunnel. In order to identify the relationship between thepressure and quality of concrete, concrete was filled under pressure and the pressure was measuredfor testing in actual construction of lining concrete. As a result of the testing, it was verified thatpressurized filling of concrete in actual construction would be effective for increasing the strengthand tightness of concrete.