Effect of binary blending of waste paper sludge ash and granite dust in fine grained soil stabilization.

This study aims, through experimental works, to develop a new and sustainable binder by reusing two waste materials, namely waste paper slag ash (WPSA) and granite dust (GD) to stabilize fine-grained soil and reduce the environmental impacts resulting from improper disposal in addition to reducing the use of cement and lime in soil stabilization. The soil utilized in this research was obtained from a site near 80th Street in Babylon Provence. The experimental works included sieve and hydrometer analysis, consistency limits, compaction test, and unconfined compression strength test at 3, 7, and 28 days of curing. Various binary blended binders derived from mixing of WPSA and GD at different proportions; 10:0, 7.5:2.5, 5:5, 2.5:7.5, and 0:10 were utilized. These binary blended binders were mixed with the virgin soil at 10% in the samples testing procedure. The results showed that the use of the mixture containing GD alone resulted in a reduction in the LL, PL, and PI, and when increase the percentage of WPSA in the mixture, LL and PL were increased while PI decreased. Moreover, the maximum dry density of the treated soil increased with the use of GD, however, it decreased significantly after the employing WPSA in the binder used. As per the outcomes of the compressive strength test, it was shown that the use of the mixture WPG0 that contains (100% WPSA) gave the highest compressive strength, which is equivalent to 14 times of that for the virgin soil after 28 days of curing. The strength then dropped with increasing the percentage of granite dust in the mixture. However, mixtures contained both of WPSA and GD exhibited acceptable compressive strength throughout the time of curing as the results indicated. [ABSTRACT FROM AUTHOR]