A Study for Carbonation Degree on Concrete using a Phenolphthalein Indicator and Fourier-Transform Infrared Spectroscopy

A concrete structure is designed and constructed for its purpose of use, and is expected to maintain its function for the target durable years from when it was planned. Nevertheless, as time elapses the structure gradually deteriorates and then eventually degrades to the point where the structure cannot exert the function for which it was planned. The performance of concrete that is able to maintain the level of the performance required over the designed period of use as it has less deterioration caused by the elapse of time under the designed condition is referred to as Durability. There are a number of causes of durability degradation, but especially chloride damage, carbonation, freeze-thaw, etc are the main causes. In this study, carbonation, one of the main causes of deterioration of the durability of a concrete structure, was investigated via a microstructure analysis technique. The method for the measurement of carbonation was studied using the existing indicator method, and the method of measuring the progress of carbonation in a quantitative manner was simultaneously studied using a FT-IR (Fourier-Transform Infrared) Spectrometer along with the microstructure analysis technique.

Authors:

• Ho Jae Lee
• Do Gyeum Kim
• Jang Hwa Lee
• Myoung Suk Cho

Keywords:

• Concrete
• Carbonation
• Microsturcture
• FT-IR

References:

[1] M.D. Cohen and A. Bentur, Durability of Portalnd cement -silica fume
pastes in magnesium sulfate and sodium sulfate solution, ACI Materials
Journal, Vol. 85, 148-157, 1988.
[2] C. Chang and J. Chen, The experimental investigation of concrete
carbonation depth, Cement and Concrete Research, Vol. 36, No. 9,
1760-1767, 2006.
[3] C. Alonso, C. Andrade and J.A. Gonzalez, Relation between resistivity
and corrosion rate of reinforcements in carbonated mortar made with
several different cement types, Cement and Concrete Research, Vo. 18,
pp. 687-698, 1988
[4] C.L. Page and O. Vennesland, Pore solution composition and chloride
binding capacity of silica fume cement pastes, Material Structures, Vol
16, pp 19-25, 1983.
[5] M. Pourbaix, Atlas of electrochemical equilibria in aqueous solutions. 2d
English ed. 1974, Houston, Tex.: National Association of Corrosion
Engineers.
[6] RILEM Draft Recommendation CPC-18, Measurement of hardened
concrete carbonation depth, Material structures, Vol. 17, pp. 434-440,
1984
[7] J.W. Hwang, Y. Lee, and D.H. Lee, Morphological Change of
Precipitated Calcium Carbonate by Reaction Rate in Bubble Column
Reactor, Korean Chemical Engineering Research, Vol 47, No. 6,
December, pp. 727-733, 2009
[8] G. Villain, M. Thiery and G. Platret, Measurement methods of
carbonation profiles in concrete: Thermogravimetry, chemical analysis
and gammadensimetry, Cement and Concrete Research, Vol. 47, No. 8,
1182-1192, 2007.
[9] V.W.Y. Tam, X.F. Gao and C.M. Tam, Carbonation around near
aggregate regions of old hardened concrete cement paste, Cement and
Concrete Research, Vol. 35, No. 6, 1180-1186, 2005.