UNDERWATER RIPRAP REPARATION-AND-REINFORCEMENT TECHNIQUE FOR GRAVITY-TYPE PIERS AND INVESTIGATION OF ITS EFFECTIVENESS

摘要

This paper discusses a reinforcement method for pouring high-pressure non-dispersive mortar into underwater piers of riprap, and an integrated detection method for the effectiveness of the reinforcement. For verifying the high-pressure grouting enforcement quality, we apply comprehensive non-destructive geophysical methods including ground penetrating radar (GPR) and elastic wave tomography, incorporating with wave velocity test and point loading strength test for core samples. Elastic wave tomographic results show that the velocity of high-quality pouring region increases and that of the low-quality pouring region is low. GPR profiles indicate that the reflection strength from the interface between solid and hollow concrete layers becomes weak after pouring. Core samples verify these phenomena.