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  2. Sulfate attack in concrete and mortar - Wikipedia

    en.wikipedia.org/wiki/Sulfate_attack_in_concrete...

    Oxidation of pyrite in clay formations in contact with concrete – this produces sulfuric acid which reacts with concrete. Bacterial activity in sewers – anaerobic sulfate reduction at work in the organic-rich sludges accumulated under water in the conduits produces hydrogen sulfide gas (H 2 S).

  3. Concretion - Wikipedia

    en.wikipedia.org/wiki/Concretion

    On the other hand, iron sulfide concretions, which either are composed of or contain either pyrrhotite or smythite, will be magnetic to varying degrees. [80] Prolonged heating of either a pyrite or marcasite concretion will convert portions of either mineral into pyrrhotite causing the concretion to become slightly magnetic.

  4. Iron sulfide - Wikipedia

    en.wikipedia.org/wiki/Iron_sulfide

    Iron sulfide or Iron sulphide can refer to range of chemical compounds composed of iron and sulfur. Minerals. By increasing order of stability: Iron(II) sulfide, FeS;

  5. Iron(II) sulfide - Wikipedia

    en.wikipedia.org/wiki/Iron(II)_sulfide

    Iron(II) sulfide or ferrous sulfide (Br.E. sulphide) is one of a family of chemical compounds and minerals with the approximate formula Fe S. Iron sulfides are often ...

  6. Concrete degradation - Wikipedia

    en.wikipedia.org/wiki/Concrete_degradation

    It is the considerable forces internally created by the expansion of the iron corrosion products (about 6 – 7 times less dense than metallic iron, so 6 – 7 times more voluminous) that cause the cracks in the concrete matrix and destroy reinforced concrete. In the absence of iron (and without some harmful chemical degradation reactions also ...

  7. Biogenic sulfide corrosion - Wikipedia

    en.wikipedia.org/wiki/Biogenic_sulfide_corrosion

    The hydrogen sulfide gas is biochemically oxidized in the presence of moisture to form sulfuric acid. The effect of sulfuric acid on concrete and steel surfaces exposed to severe wastewater environments can be devastating. [1] In the USA alone, corrosion causes sewer asset losses estimated at $14 billion per year. [2]

  8. Ground granulated blast-furnace slag - Wikipedia

    en.wikipedia.org/wiki/Ground_granulated_blast...

    Samples of "ground granulated blast furnace slag" (left) and "granulated blast furnace slag" (right) Ground granulated blast-furnace slag (GGBS or GGBFS) is obtained by quenching molten iron slag (a by-product of iron and steel-making) from a blast furnace in water or steam, to produce a glassy, granular product that is then dried and ground into a fine powder.

  9. Acid sulfate soil - Wikipedia

    en.wikipedia.org/wiki/Acid_sulfate_soil

    These soils contain iron sulfide minerals (predominantly as the mineral pyrite) and/or their oxidation products. In an undisturbed state below the water table, acid sulfate soils are benign. However, if the soils are drained, excavated or otherwise exposed to air, the sulfides react with oxygen to form sulfuric acid. [1]