Abstract:
This study was to find a treatment technique to reduce the water
absorption of Recycled Aggregates (RA) which involved preparing a coating to
reduce the water penetration. The materials considered for the preparation of
coating was Termite Mound Soil (TMS) and ordinary Portland cement. The objective
was to find their optimum proportions and the slurry thickness for a coating that
gives the lowest absorption. TMS was tested for pozzolanic properties. Chemical
composition was tested using Atomic Absorption Spectroscopy and other analytical
techniques. Water absorption, particle size distribution, AIV, LAAV of RA was
tested to ensure the suitability for construction purposes. Slurries were prepared
using cement replacement levels of 0, 20, 40, 60 and 80% of TMS. Three sets of
coatings were prepared with water to solid ratios of 1, 1.25 and 1.5. Slurries were
prepared in a concrete mixture in which the aggregates were coated for 10 minutes
at a speed of 30rpm. After air drying, coated aggregates were tested for the
absorption after 14 days. The absorption of treated aggregates was compared with
those of natural and untreated recycled aggregates. Aggregates Coated using 50%
cement and 50% TMS showed a significant reduction in the water absorption up to
38.44%.
Citation:
Madawa, W.K.A., Rathnayake, R.M.S.I.B., Wijethunga, D.B., Gamage, T.C., & Karunarathne, S. (2015). Development of a treatment technique to reduce the water absorption capacity of recycled aggregates. In P.V.A. Hemalal (Ed.), Proceedings of the 9th Annual ERE Research Conference on Earth Resources Management (pp. 52-57). Department of Earth Resources Engineering, University of Moratuwa.
