Authors:
Sushil Sagar Sharma; Rakesh Kumar Dutta; Raman Parti;
Abstract:
This paper presents the geotechnical characterization of flyash-redmud mix stabilized with lime sludge. Compaction tests were carried out on flyash-redmud and flyash-redmud-lime sludge mixes. The results of this
study revealed that maximum dry unit weight increased with the increase in percentage of redmud in flyash. The optimum moisture content decreased with the increase in the content of redmud upto 20% in flyash. Beyond a content of 20% of redmud in flyash, the optimum moisture content increased. A mix containing 30% flyash and 70% redmud was identified and used for studying the compaction behaviour by varying the content of lime sludge. The maximum dry unit weight of the mix increased up to a lime sludge content of 2%. Beyond a lime
sludge content of 2%, the dry unit weight decreased. A reference mix containing 30% flyash and 70% redmud, with 2% lime sludge was identified and used for studying the unconfined compressive strength, split tensile strength, bearing ratio, unconsolidated undrained triaxial behaviour and durability of the cured specimens. The
curing period was varied from 7 days to 90 days. The results revealed that unconfined compressive strength, split tensile strength, bearing ratio and deviator stress of the reference mix increased with the increase in curing period. The durability of the reference mix improved after the wetting and drying cycles. The trend is the same
at all curing periods. The improved behaviour of the flyash-redmud-lime sludge mix will boost the construction of subgrade in roads. Further, its use will also provide environmental motivation for providing a means of consuming large quantities of flyash, redmud and lime sludge.
Keywords:
Flyash, Redmud, Lime sludge, Compaction, Unconfined compressive strength, Bearing ratio, Deviator stress, Durability, Split tensile strength, EDAX, FESEM