STRENGTH PROPERTIES OF DREDGED SILT AT HIGH WATER CONTENT TREATED WITH SODIUM SILICATE, SODA RESIDUE AND GROUND GRANULATED BLASTFURNACE SLAG

Two industry by-products, soda residue(SR) and ground granulated blastfurnace slag(GGBS), and sodium silicate(SS)were utilized to stabilize dredged silt at high water content. The unconfined compressive tests and X-ray diffraction were conducted to analyze the strength characteristics and the mechanism. The results indicate that the increase in dosage of SS, SR and GGBS can increase the unconfined compressive strength for the samples with the initial water content of 110%. The order of factors for strength of 3 days curing is SS > SR > GGBS. The order changes to SS > SR > GGBS for samples cured for 7 and 28 days. SS has a significant impact on the strength of 28 days curing. When the dosage of SS is fixed and the total dosage of SR and GGBS is the same, the effect of SR is stronger than that of GGBS. The hydration reaction among SS, SR, GGBS and soil minerals produces hydration products including ettringite, calcium chloro-aluminate hydrates, gismondine, and calcium silicate hydrates. They play the filling-in and cementation effects. The solidification scheme to meet the requirement of fill construction was determined. The results can provide a theoretical basis and data support for the resource utilization of SR and GGBS as stabilizer for dredged silt at high water content.