EFFECT OF SELF HEALING PROMOTED MATERIALS BLENDED WITH CARBOXYLIC ACID ON PERMEABILITY

A kind of calcite crystalline proliferation cementitious mixture consisting carboxylic acid and carbonate salts used as self healing promoted materials (SHPM) was presented. Study was focused upon formulating the leaching and deposition equilibrium process of calcite crystals proliferated by SHPM during direct hydraulic permeability test. Results of permeability experiments and Environmental Scanning Electron Microscopy (ESEM) observation confirmed the properties of self healing of the materials. Comparing to blank paste sample, the permeability of paste coated with SHPM reduced significant with the elapse of time, while the permeability of paste blended with magnesium salt and cured in dilute carboxylic acidic solution dramatically increased during the leaching period. Compared to maleic acid and malic acid, tartaric acid mixed in SHPM had a high efficiency to modify the crystalline morphologies of deposited calcite and aragonite. Study is aimed to give a comprehension of self healing process of concrete in ambient weak acidic saturated environment.

[1]  Xiao-yan Li,et al.  The role of Mg2+ and Mg2+/amino acid in controlling polymorph and morphology of calcium carbonate crystal , 2007 .

[2]  A. Bentur,et al.  Effect of concrete composition on durability in natural acidic environment , 2006 .

[3]  S. Granger,et al.  Self healing of cracks in concrete: from a model material to usual concretes , 2006 .

[4]  A. Bertron,et al.  Attack of cement pastes exposed to organic acids in manure , 2005 .

[5]  Å. Rasmuson,et al.  Crystal growth of aragonite and calcite in presence of citric acid, DTPA, EDTA and pyromellitic acid. , 2005, Journal of colloid and interface science.

[6]  A. Bertron,et al.  Cement pastes alteration by liquid manure organic acids: Chemical and mineralogical characterization , 2004 .

[7]  Guang Ye,et al.  Experimental Study and Numerical Simulation of the Development of the Microstructure and Permeability of Cementitious Materials , 2003 .

[8]  R. Clemente,et al.  Morphological control of precipitated calcite obtained by adjusting the electrical conductivity in the Ca(OH)2–H2O–CO2 system , 2003 .

[9]  C. Andrade,et al.  A new leaching test based in a running water system to evaluate long-term water resistance of concretes , 2002 .

[10]  Peter A. Claisse,et al.  Permeability and pore volume of carbonated concrete , 1999 .

[11]  Yamashita,et al.  Effects of Carboxylic Acids on Calcite Formation in the Presence of Mg2+ Ions. , 1999, Journal of colloid and interface science.

[12]  Nataliya Hearn,et al.  Self-sealing, autogenous healing and continued hydration: What is the difference? , 1998 .

[13]  C. Morley,et al.  Self-sealing property of concrete—Experimental evidence , 1997 .

[14]  H. Taylor.  Modification of the Bogue calculation , 1989 .

[15]  C. Vandecasteele,et al.  Influence of carbonation and carbonation methods on leaching of metals from mortars , 2004 .