The Effect of Pozzolanics on the Recycled Aggregates by Surface Treatment

Abstract:

To improve the mechanical properties of concretes containing recycled aggregates, pozzolanic materials such as Silica Fume and Meta Kaolin were used to decrease the porosity of the recycled aggregates. These pozzolanic aterials were adhered on the surface of recycled aggregates and closed the open pores so that the water absorption was decreased 1~2% as the amount of adsorption was increased. Compressive strength of cement mortars and concretes using surface treated recycled aggregates reached above 95% of the strength of its natural counterparts. Investigation of the microstructures using the scanning lectron micrographs showed the formation of dense interface after the adsorption treatment of pozzolanics to recycled aggregates.

• Periodical: Materials Science Forum (Volumes 486-487)
• Pages: 305-308
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.486-487.305
• Online since: June 2005
• Authors: Jae Jun Kim, Sang Heum Youn, M.J. Cho, H.T. Shin, Jeong Bae Yoon, Kyu Hong Hwang, D.S. Lee
• Keywords: Colloidal Silica, Metakaolin (MK), Pozzolanics, Recycled Aggregate (RA), Silica Fume (SF)

References

[1] J.Y. Lee, A forum about the environmental preservation and a plan of waste recycling, Construction & Economy Research Institute of Korea (1997).

[2] H.D. Kim, N.Y. Leem, Concrete used cement mortar and recycled aggregate, Korean patent 10-0199998 (1999).

[3] Nixon, P. J, Recycled concrete as an aggregate for concrete, Materials and Structure, Vol. 2, No. 65, pp.371-378 (1978).

[4] Ravindrajah, S. T. and Tam C. T., Recycling concrete as fine aggregate in concrete, J. of Cement Composites and Lightweight Concrete, Vol. 9, No. 4, pp.235-241 (1988).

DOI: 10.1016/0262-5075(87)90007-8

[5] J.J. Kim, S.H. Youn, K.H. Hwang, Enhancement of the Properties of Recycled Aggregates by the Pozzolanics, pp.115-120 of The Proceeding of 31th Cement Symposium, Korean Ceramic Society (2004).