Fly ash for concrete - Requirements
NCh 3520:2020 Cenizas volantes para hormigón - Requisitos (Chilean Standard (NCh) No. 3520:2020, Fly ash for concrete - Requirements) (9 pages, in Spanish)
The notified Standard establishes the requirements governing the physical and chemical properties of, and the quality control procedures for, fly ash as defined in Article 3.1, for use as an addition in the production of concrete compliant with NCh No. 170. Fly ash conforming to this Standard may also be used in mortars and grouts. (1.2) This Standard covers the use of fly ash obtained directly from the combustion of pulverized coal in thermal power plants. (1.3) This Standard does not apply to fly ash collected from its disposal site, unless the electricity generator takes measures so that ash may be collected or processed in a manner that ensures it is suitable, homogeneous and contamination-free, for use in concrete. (1.4) This Standard does not apply to ash obtained from co-combustion and from municipal, agricultural, forest and industrial waste incineration. (1.5) It is beyond the scope of this Standard to specify provisions governing the production of concrete, i.e. requirements concerning composition, mixing, placing, curing etc. of concrete containing fly ash. As regards such provisions, reference should be made to other standards for concrete, such as NCh No. 170.