Concrete is a widely used material in the world. Concrete as an exterior component must resist to severe aggressive agents and reactive agents. Carbonation of concrete is one type of concrete deteriorations which are able to deliver corrosion of reinforced bars and change the characteristic of concrete material. Generally, the detection of carbonation was conducted using phenolphthalein 1% solution. However, previous experiment showed that this method is destructive and may not be able to indicate the significance of detailed carbonation. Therefore, this paper focuses on developing a nondestructive ultrasonic pulse velocity method to estimate the carbonation depth with a signal processing technique, called Haar wavelet transform (HWT). In this research, the transformation result of HWT transformation is used to evaluate the carbonation damaged of concrete material from numerical simulation of finite element model. Then this method is also verified by experimental work.
Numerical simulation with ultrasonic wave propagation is delivered by using the commercial finite element analysis software LS-DYNA in which a 2-D axisymmetric finite element model is used to simulate concrete carbonated model of 40 mm of thickness and 60 mm of length. Two layers, three layers, four layers and five layers consist of carbonated layer with different thickness overlaying and percentage increase (%) of Young’s modulus (17%14%) overlaying un-carbonated concrete (ordinary concrete).
The numerical results show that Haar wavelet transform could be used for depth detection with an error less than 3% and the accuracy of detection depends on the acoustic impedance (Z) at each layer of carbonation models. A double layered and multi layered carbonation models with ratio of acoustic impedance higher than 1.20 could be effectively identified carbonation layered.

Concrete is a widely used material in the world. Concrete as an exterior component must resist to severe aggressive agents and reactive agents. Carbonation of concrete is one type of concrete deteriorations which are able to deliver corrosion of reinforced bars and change the characteristic of concrete material. Generally, the detection of carbonation was conducted using phenolphthalein 1% solution. However, previous experiment showed that this method is destructive and may not be able to indicate the significance of detailed carbonation. Therefore, this paper focuses on developing a nondestructive ultrasonic pulse velocity method to estimate the carbonation depth with a signal processing technique, called Haar wavelet transform (HWT). In this research, the transformation result of HWT transformation is used to evaluate the carbonation damaged of concrete material from numerical simulation of finite element model. Then this method is also verified by experimental work.
Numerical simulation with ultrasonic wave propagation is delivered by using the commercial finite element analysis software LS-DYNA in which a 2-D axisymmetric finite element model is used to simulate concrete carbonated model of 40 mm of thickness and 60 mm of length. Two layers, three layers, four layers and five layers consist of carbonated layer with different thickness overlaying and percentage increase (%) of Young’s modulus (17%14%) overlaying un-carbonated concrete (ordinary concrete).
The numerical results show that Haar wavelet transform could be used for depth detection with an error less than 3% and the accuracy of detection depends on the acoustic impedance (Z) at each layer of carbonation models. A double layered and multi layered carbonation models with ratio of acoustic impedance higher than 1.20 could be effectively identified carbonation layered.

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