Assessing device, assessing system, assessing method, and computer-readable recording medium

An assessing method comprising:

• identifying a dominant frequency of a vibration at each of a plurality of spots in a structure, based on information indicating the vibration at each of the plurality of spots;
• identifying a phase difference at the dominant frequency between the vibrations at two spots included in the plurality of spots, based on the dominant frequency and the information indicating the vibrations;
• and
• assessing a damage in the structure, based on a change rate of the phase difference between the two spots and a phase difference at a reference timing for same spots.

A computer-readable recording medium that non-temporarily stores a program causing a computer to perform:

• processing of identifying a dominant frequency of a vibration at each of a plurality of spots in a structure, based on information indicating the vibration at each of the plurality of spots;
• processing of identifying a phase difference at the dominant frequency between the vibrations at two spots included in the plurality of spots, based on the dominant frequency and the information indicating the vibrations;
• and
• processing of assessing a damage in the structure, based on a change rate of the phase difference between the two spots and a phase difference at a reference timing for same spots.