Abstract
The reinforced concrete rigid-frame viaducts of the Tokai Shinkansen experience significant vertical pile motion during train passage in some places and the presence of minor cracks in upper longitudinal beam haunches has been confirmed. While impact vibration and other tests have not detected problems in the base bearing capacity of these viaducts, the carbonation of concrete is progressing, raising concern as a potential cause of rebar corrosion. Against this backdrop, focusing on the vertical spring of the base of viaducts, the authors investigated a base reinforcement method for viaducts to improve the vertical spring of the base through the effective use of the vertical spring of the existing base, and carried out test construction and effect verification measurements. The authors confirmed improvement in the vertical spring of the base and reduction of vertical pile motion through viaduct base reinforcement, and developed specifications for viaduct base reinforcement.
