Use of fine recycled concrete aggregates in concrete: A
The crushing of concrete generates more adhered cement paste in fRCA, resulting in higher contents of soluble alkalis and sulfates in fRCA than in coarse recycled concrete aggregates. The alkalis were shown to be less stable in adhered cement paste The investigated scales of fine aggregate with sulfates contents were (0.37%, 0.5%, 1.0%, and 1.5%) which is corresponding replacement by weight of cement (PDF) SULFATES EFFECT IN FINE AGGREGATE ON SELF
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Internal sulfate attack in mortars containing contaminated
The water soluble sulfates in FRA are responsible for a deterioration when they react with C 3 A and water in a new cementitious mix. These sulfates could The effect of sulfate attack (SA) on the strength of ultrahigh-performance concrete (UHPC) made with different replacements (0%, 50% and 100% by weight) of Sulfate resistance of ultrahigh-performance concrete with recycled
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Discussion and experiments on the limits of chloride,
Contents of chloride, sulphate and shell in the marine aggregates can influence the properties of concrete and corresponding performance of the concrete 0.40 and 0.60. The sulfate resistance of concrete mixtures was evaluated using prolonged exposure in a concentrated sulfate solution in accordance with USBR Test 4908. The An ACI Technical Publication American Concrete Institute
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Evaluation of sulfate resistance of cement mortars with
In this study, fine stone powder (FSP) generated in the process for producing crushed coarse and fine aggregate was used as a partial replacement for the Download scientific diagram Grading and sulfate content of Fine Aggregate from publication: EFFECT OF POST TENSIONING TENDONS DISTRIBUTION ON STIFFNESS AND DUCTILITY PROPERTIES OF Grading and sulfate content of Fine Aggregate
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Compressive strength assessment of sulfate-attacked
Abstract. Sulfate attack is a major cause of concrete durability deteriorations. Mass loss, strength reductions, and expansive strain of concrete In this study, fine stone powder (FSP) generated in the process for producing crushed coarse and fine aggregate was used as a partial replacement for the fine aggregate. The durability of mortars was investigated under sulfate attack in terms of compressive strength loss, change in mass, and expansion. Cement mortars were made Evaluation of sulfate resistance of cement mortars with the
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(PDF) Studying The Effect of Internal Sulfates on
Each group consisting of four set with different ratio of sulfate (0.28% (reference SO3), 0.5%, 1% and 1.5%) by weight of fine aggregate where these ratios approximate the actual reality of theAlthough mixing ratios were constant in all mixtures, the only difference was the percentage of fine aggregate (sand), which was equal to (0.2%) in the first mix and (2.1%) in the second mix. The Iraqi standard specification No.45 (1984) limited the upper limit of sulfate content in the sand not exceeded (0.5%).Solving high sulfate content of sand used in concrete by
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Internal sulfate attack in mortars containing contaminated fine
Internal sulfate attack in mortars containing contaminated fine recycled concrete aggregates. Author links open overlay panel C Sulfate content A sulfate Use of a reference limestone fine aggregate to study the fresh and hard behavior of mortar made with recycled fine aggregate. Materials and Structures, 52 (2019), pp. 1-14Current Hong Kong standard “CS3: 2013 Aggregates for Concrete” [27] still adopts the regulations in the canceled BS 882-1992 [18] about the chloride content in compound aggregates including fine and coarse aggregates, which are: 0.01% for pre-stressed concrete and steam-cured structural concrete, 0.03% for structural concrete Discussion and experiments on the limits of chloride, sulphate and
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EFFECTIVE SULFATE CONTENT IN CONCRETE INGREDIENTS
The problem of internal sulfate attack in concrete is widespread in Iraq and neighboring countries. This is because of the high gypsum content usually present in sand and gravel used in concrete. Specifications usually put upper limits of SO3 content in cement, aggregate and concrete. The upper limit of SO3 content is calculated The incorporation of a recycled concrete aggregate (RCA) as a replacement of natural aggregates (NA) in road construction has been the subject of recent research. This tendency promotes sustainability, but its use depends mainly on the final product’s properties, such as chemical stability. This study evaluates the physical and The Chemical-Mineralogical Characterization of Recycled Concrete
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The effect of aggregates with high gypsum content on the
Section snippets Materials. Natural river sand (0–4 mm) and commercial quartz sand (0.6–1.2 mm and 1.2–2.5 mm) with a specific gravity of 2.66 and 2.65, respectively were used as fine aggregates.The natural crushed gypsum with the SO 3 content of nearly 38% was used as a partial substitution of the natural river sand to raise The effect of sulfate attack (SA) on the strength of ultra-high performance concrete (UHPC) with recycled fine aggregate (RFA) is investigated. RFA is used to replace natural fine aggregate (NFAInternal sulfate attack in mortars containing contaminated fine
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(PDF) SULFATES EFFECT IN FINE AGGREGATE ON SELF COMPACTING CONCRETE
The sulfate content in fine aggregate contains sulfate higher than the acceptable limi ts in most of the fine aggregate in Middle East countries ( Al -Kadhimi and Hamid, 1983) .Sulfate attack on concrete is a key durability problem. Internal sulfate attack (ISA) on concrete is a reaction between sulfates present in the original mix of concrete and the calcium aluminate in Deterioration Process of Concrete Exposed to Internal
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Cement Standards and Concrete Standards Standards Products
Aggregate Reactions in Concrete. C1105-08a(2016) C1137-05 Standard Test Method for Degradation of Fine Aggregate Due to Attrition (Withdrawn 2011) Sulfate Content. C1038/C1038M-19 Standard Test Method for Expansion of Hydraulic Cement Mortar Bars Stored in Water .The used egg shells were used as fine concrete aggregate. In the laboratory test, conventional fine aggregate was replaced at 100% replacement level. A total of 18 cubes were cast, cured and tested.(PDF) Egg Shell As A Fine Aggregate In Concrete For
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Evaluation of Aggregate Durability Performance Test Procedures
repetitive freeze/thaw cycles. At the end of the test, the aggregate grading is analyzed to determine the percent loss of the aggregate sample. Typical limits on percent loss are 12 percent for coarse aggregate and 15 percent for fine aggregate. In Arkansas, aggregate soundness is governed by the sodium sulfate soundness test.2. Impermeability. Impermeability is a characteristic of the durability of concrete and is closely related to other durability characteristics. For example, water-soluble chloride ions, CO 2, and sulfate can enter concrete, or other external factors can cause damage to the concrete, making the service life of concrete greatly affected and thus The Durability of Recycled Fine Aggregate Concrete: A Review
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Behavior of High Performance Concrete Exposed to Internal Sulfate
Four sulfate contents (0.5, 1.5, 2.0, and 2.5 %) in fine aggregate were studied. Metakaolin was used as a pozzolanic material, which has proved itself as a good active one.It also recommends maximum sulfate content in the used fine and course aggregate as 0.4% by weight of aggregate and maximum total sulfate content in used concrete as 4% by weight of cement. No additional recommendations are suggested in case of used concrete aggregate with sulfate content more than the maximum Four-years carbonation and chloride induced steel corrosion of sulfate
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The effect of aggregates with high gypsum content on the
There is an increasing demand to ultra-high strength cement-based materials in the Middle East despite finding fine aggregates with a normal SO 3 level is a major challenge. This study was conducted to investigate the effect of increasing gypsum content of natural river sand on the properties of water and steam cured ultra-high used aggregate types in Sri Lanka during the last two years were crushed rock as coarse aggregate and river sand as fine aggregate for concrete. All the samples of coarse aggregate tested complied with the requirements specified in respect of all tests carried out except the requirements on grading and abrasion. In the case of fine aggregateA Study on Types and Quality NBRO
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Long-term sulfate attack on recycled aggregate concrete immersed in
In this paper, recycled aggregate concretes (RAC) with 0, 50, 75 and 100% of RCA contents were evaluated after 10 years of exposure immersed in 50g/l sodium sulfate solution.
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