A system and related method can self-adaptively absorb a flexural wave acting on a beam. The method includes the steps of receiving an input signal representing a frequency response of a flexural wave acting on the beam, determining a spring constant for absorbing the flexural wave based on the input signal, a damping value of a damper acting on the beam, and a mass value of a mass acting on the beam, and applying a spring constant voltage based on the spring constant to a piezoelectric device connected to the beam. The piezoelectric device has a variable spring value that varies based on the voltage applied to the piezoelectric device. The piezoelectric device's variable spring value is approximately equal to the spring constant value when the spring constant voltage is applied to the piezoelectric device.