Nondestructive diagnostics and damage evaluation of farm ponds due to the Tohoku Region Pacific Coast Earthquake

Abstract

Tohoku Region Pacific Coast Earthquake hit in Japan on March 11, 2011. A large number of water storage facilities were damaged due to the 9.0 magnitude earthquake of the Richter-scale. Prior to reconstruction and retrofit of these structures, damage evaluation of in-situ structures is now in urgent demand. In this concern, damaged dams were investigated (n=143) and qualitative evaluation of damage was conducted by 3D-resistivity survey and microtremor measurement in deteriorated dam bodies (n=2). Thus, the deteriorated of dam body could be evaluated by specific resistance with H/V spectral ratio by microtremor monitoring. A relation between structural damage and monitoring parameters is correlated in deteriorated dam bodies.