Properties of concrete prepared with PVA-impregnated recycled concrete aggregates

This paper reports an experimental study to improve the properties of recycled concrete aggregates (RCA) by their impregnation with polyvinyl alcohol (PVA). The effects of PVA on the development of strength and durability properties of the recycled aggregate concrete were evaluated. The experimental investigation was conducted in two parts. Firstly, the optimal concentration of PVA solution required to improve the recycled aggregates was determined. The RCA was soaked in 6%, 8%, 10%, 12% PVA solutions, and impregnation was conducted under a controlled laboratory environment. Density, crushing value (10% fines value), and water absorption of the PVA impregnated RCA (PI-RCA) were determined. Secondly, the slump, slump loss, compressive and tensile splitting strength, dimensional change (shrinkage) and chloride penetrability of the concretes prepared with the RCA that had been impregnated with the optimal (10%) PVA concentration were determined. It was found that the 10% fines value of the PI-RCA was higher, and the water absorption of the PI-RCA were lower when compared to the untreated RCA. The results show that there was not only an improvement in the mechanical properties of the concrete made with PI-RCA, but also the shrinkage of PI-RCA decreased while the resistance to chloride-ion penetration of the concrete produced increased.

[1]  Vivian W. Y Tam,et al.  Diversifying two-stage mixing approach (TSMA) for recycled aggregate concrete: TSMAs and TSMAsc , 2008 .

[2]  Y. Ohama,et al.  POLYMER-BASED ADMIXTURES , 1998 .

[3]  Bje Richardson,et al.  USE OF RECYCLED CONCRETE AS A ROAD PAVEMENT MATERIAL WITHIN AUSTRALIA , 1994 .

[4]  I. Topcu.  Physical and mechanical properties of concretes produced with waste concrete , 1997 .

[5]  Masafumi Narikawa,et al.  Application of recycled coarse aggregate by mixture to concrete construction , 2007 .

[6]  Sarita Rai,et al.  Effect of polyvinyl alcohol on the hydration of cement with rice husk ash , 2001 .

[7]  Nik.D. Oikonomou,et al.  Recycled concrete aggregates , 2005 .

[8]  Manabu Kanematsu,et al.  Application of Conventionally Recycled Coarse Aggregate to Concrete Structure by Surface Modification Treatment , 2007 .

[9]  R. E. Robertson,et al.  Effects of Polyvinyl Alcohol on Aggregate-Paste Bond Strength and the Interfacial Transition Zone , 1998 .

[10]  J. Larbi,et al.  Influence of polymer modification on the hydration of portland cement , 1991 .

[11]  C.-S. Poon,et al.  Mechanical properties of 5-year-old concrete prepared with recycled aggregates obtained from three different sources , 2008 .

[12]  I. Joekes,et al.  Macro-defect free cements Influence of poly(vinyl alcohol), cement type, and silica fume , 1999 .

[13]  C. Poon,et al.  Influence of moisture states of natural and recycled aggregates on the slump and compressive strength of concrete , 2004 .

[14]  J. F. Young,et al.  A review of the mechanisms of set-retardation in portland cement pastes containing organic admixtures , 1972 .

[15]  Brian Joseph Edward Richardson.  Recycling waste concrete into road pavement aggregate , 1995 .

[16]  Ahmad Shayan,et al.  PERFORMANCE AND PROPERTIES OF STRUCTURAL CONCRETE MADE WITH RECYCLED CONCRETE AGGREGATE , 2003 .

[17]  I. Topcu,et al.  Properties of concretes produced with waste concrete aggregate , 2004 .

[18]  Chi Sun Poon,et al.  The use of recycled aggregate in concrete in Hong Kong , 2007 .

[19]  Alan D. Buck.  Recycled Concrete as a Sourceof Aggregate , 1977 .

[20]  Nobuaki Otsuki,et al.  Influence of Recycled Aggregate on Interfacial Transition Zone, Strength, Chloride Penetration and Carbonation of Concrete , 2003 .

[21]  R. E. Robertson,et al.  Structure and properties of poly(vinyl alcohol)-modified mortar and concrete , 1999 .

[22]  D. Santos,et al.  A microstructural approach to adherence mechanism of poly(vinyl alcohol) modified cement systems to ceramic tiles , 2007 .

[23]  Alan D. Buck.  Recycled concrete as a source of aggregate , 1976 .