Analysis on the Influence law and Mechanism of the Strength of Reclaimed Aggregate-Industrial Waste Slag Solidified Silt

Abstract

To optimize the usage of construction waste resources, industrial waste slag and silt, this paper used Portland cement, mineral waste residue and phosphogypsum composite to make cementing material (CMPS) with construction waste reclaimed aggregate to solidify silt. The laboratory solidification test and microscopic analysis were conducted to assess the mechanical characteristics of solidified sludge. In order to clarify the mineral composition, microscopic morphology and pore characteristics of the regenerated aggregate and CMPS solidified silt (SS), XRD, SEM and nitrogen adsorption pore analyzer were employed for further explore the regenerated aggregate and CMPS solidified silt effectively, and further reveal the internal mechanism of the regenerated aggregate and CMPS solidified silt effectively. The findings indicated that the strength of Portland cementmineral waste residue phosphogypsum terpolymer system curing agent increased by 107.34% than that of single Port-land cement SS at 56 d, and the strength of CMPS solidified silt increased by 25.68% under the action of reclaimed aggregate framework. The maintenance period and water composition of the silt have high correlation with the strength. Therefore, influence law of above two influencing factors on its mechanical properties were further explored and the strength prediction were made. The microscopic test results showed that, drawing from the hydration of Portland cement and pozzolans reaction of mineral waste residue, the solidified system has pre-pared CaSiO3 hydrate gel and ettringite crystals with gelatinous properties, which help to fill the pores and form a denser structure.