EARLY-AGE CONCRETE STRENGTH ESTIMATION APPARATUS AND METHOD FOR USING IMPEDANCE

PURPOSE: A device and a method for estimating the initial strength of concrete using impedance are provided to bury a piezoelectric element sensor in the inside of a concrete structure and to evaluate the initial strength by estimating the strength for 20 hours after placing concrete by using a change of the impedance in the piezoelectric element sensor. CONSTITUTION: A device and a method for estimating the initial strength of concrete using impedance comprises a piezoelectric element sensor(110), an impedance measuring device(120), and a controller(130). The piezoelectric element sensor is buried in the inside of a concrete structure and generates vibration by receiving frequency signals input from outside and outputs by converting responses by the vibration into voltage signals. The impedance measuring device is connected to the piezoelectric sensor with wires, thereby generating and outputting auxiliary voltage signals to the piezoelectric element sensor per a predetermined time unit and measures an impedance value by receiving the voltage signals being output from the piezoelectric element sensor. The controller substitutes the maximum value of the impedance value measured by the impedance measuring device with an initial strength estimating equation, thereby estimating the initial strength of the concrete structure.