Reduction of nitrobenzene by steel convert slag with Fe(II) system: The role of calcium in steel slag

To clarify the role of steel slag powder in blended cement, steel slag powders with different amounts and particle sizes were mixed into blended cement and the inert quartz powder was selected as the reference. The influences of steel slag powder with different amounts and particle sizes on the hydration and hardening properties of blended cement were studied from hydration heat, nonevaporable water content, porosity, hydration products, and strength. The results show that the influence coefficient of nonevaporable water content (ՓWn) of blended cement paste is in an exponential relationship with the amount of steel slag powder. Moreover, at a dosage of 30%, ՓWn of blended cement gradually decreases with the increase of steel slag particle size. Both the early and late compressive strengths of blended cement are in a binomial relationship with the amount of steel slag powder. The influence coefficient of steel slag powder on the compressive strength of blended cement is negative at the age of 3 days, whereas it is positive at the age of 28 days. The chemical filling effect of 30% steel slag powder with different particle sizes in the blended cement paste is very small, only 1.13%–5.06%. The hydration products of blended cement containing steel slag are mainly amorphous C-S-H gels and platy Ca(OH)2, and their density are consistent with the law of their porosity.

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The role of carbonated steel slag on mechanical performance of ultra-high performance concrete containing coarse aggregates

Construction and Building Materials ◽

10.1016/j.conbuildmat.2021.124903 ◽

2021 ◽

Vol 307 ◽

pp. 124903

Author(s):

Shaohua Li ◽

Gang Liu ◽

Qingliang Yu

Keyword(s):

High Performance ◽

Mechanical Performance ◽

High Performance Concrete ◽

Steel Slag ◽

Ultra High Performance Concrete ◽

Coarse Aggregates

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The Role of Various Powders during the Hydration Process of Cement-Based Materials

Advances in Materials Science and Engineering ◽

10.1155/2017/8394834 ◽

2017 ◽

Vol 2017 ◽

pp. 1-9 ◽

Cited By ~ 2

Author(s):

Shuhua Liu ◽

Hongling Wang ◽

Jianpeng Wei

Keyword(s):

Early Stage ◽

Steel Slag ◽

Pozzolanic Reaction ◽

Hydration Process ◽

Limestone Powder ◽

Strength Development ◽

Early Hydration ◽

Cement Based Materials ◽

Early Strength

The role of various powders including glass powder (GP), limestone powder (LP), and steel slag powder (SSP) during the hydration process of cement-based materials was investigated by using X-ray diffraction (XRD), thermogravimetric and differential thermal analysis (TG-DTA), scanning electron microscopy (SEM), and strength tests. GP has adverse impact on early strength, but the pozzolanic reaction at later stage enhances the strength development greatly. LP can significantly improve early strength. SSP has a good contribution to the early and later strength of the paste when its content is less than 15%. GP has little effect on the kind of hydration products but relatively large effects on the quantity. Calcium hydroxide (CH) content of GP paste decreases over curing age gradually, which is different from pure cement paste because its pozzolanic activity consumes more CH than that generated from the cement hydration. SSP and LP mainly play a role of filling effect at early stage. Nucleating effect of LP also promotes the early hydration of cement. The hydration of LP occurs at later stage and forms the calcium carboaluminate hydrates. The hydration of SSP is relatively slow, which generates CH at later stage and is effective in the strength development.

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