Analysis of Influencing Factors on Durability of Sludge Flow Solidified Soil

Abstract

In order to transform a large amount of dredged sludge into sustainable development of land resources, this paper takes the submarine dredged sludge in Dalian Bay as the research object, and uses the composite solidified material composed of cement, fly ash and phosphogypsum to carry out flow solidification treatment. Through laboratory experiments, the influence of curing temperature, dry-wet cycle and freeze-thaw cycle on the sludge flow solidified soil was studied. The results showed that:(1) When the fly ash-cement mass ratio RFC=0.65 and the cement-sludge mass ratio RCS=0.09-0.16, the unconfined compressive strength of the 35°C sludge flow-solidified soil is the mud-solidified soil in the outdoor curing environment 1.04 times.(2) When RCS=0.11∼0.14 and RFC=0.65, the strength loss rate of silt-solidified soil after the first dry-wet cycle is the highest, respectively 43% and 50%.(3) When RCS=0.09∼0.16 and RFC=0.65, after the third freeze-thaw cycle, the strength loss rate of the sludge solidified soil is the smallest of the first five times.