GB/T 32546-2016Technical requirements for application of steel slag (English PDF)

5.1 General provisions

5.1.1 Upon exit-factory, the supplier shall provide a certificate of conformity or a exit-factory inspection report for the steel slag powder. This documentation shall include the manufacturer's name, certificate No. or exit-factory report number No., specification or grade, production date, represented quantity, the inspection results and conclusions for the batch; type inspection reports shall also be provided periodically.

5.1.2 The technical requirements for steel slag powder shall comply with the requirements of GB/T 20491.

5.1.3 Inspection items for steel slag powder upon receipt shall include specific surface area, fluidity ratio, activity index, soundness; the inspection results shall comply with the provisions of GB/T 20491.

5.1.4 Sampling and testing of steel slag powder shall comply with the following provisions.

a) Group-batching principles. An inspection batch of steel slag powder shall consist of material from the same manufacturer, of the same activity grade, with the same exit-factory batch number; the total quantity of each inspection batch shall not exceed 200 t;

b) Sampling methods. For bulk steel slag powder, equal-sized specimens (each weighing no less than 5.0 kg) shall be taken from any 3 containers within a continuously purchased batch; these shall be mixed thoroughly; the quartering method shall be used to reduce the specimen size to twice the amount required for testing. For bagged steel slag powder, 10 bags shall be randomly selected from each batch; equal-sized specimens (each weighing no less than 1.5 kg) shall be taken from each bag; these shall be mixed thoroughly; the quartering method shall be used to reduce the specimen size to twice the amount required for testing;

c) Acceptance criteria. Acceptance of steel slag powder shall be conducted on a batch basis; material meeting the specified technical requirements for the inspection items may be used. If any performance item fails to meet the requirements, double the sample quantity shall be taken from the same batch, for re-inspection of the non-compliant item. If the performance index meets the requirements upon re-inspection, the batch may be deemed qualified; if any performance item still fails to meet the requirements, the batch shall be downgraded for use or deemed unqualified.

5.1.5 During storage, steel slag powder shall be strictly prevented from mixing with other materials and from becoming damp. If the storage period exceeds 3 months, re-inspection shall be conducted, in accordance with the provisions of 5.1.3 and 5.1.4 prior to use.

5.1.6 Measures shall be taken during the transportation of steel slag powder, to prevent the inclusion of foreign matter and the emission of airborne dust.

5.2 Cement

When steel slag powder is used as a cement blending component, its dosage shall comply with the provisions of current national standards.

5.3 Concrete

5.3.1 Other raw materials used for concrete shall comply with the following requirements.

a) Cement shall comply with the provisions of GB 175; Portland cement or ordinary Portland cement should be used. When using other types of cement, the type and dosage of admixtures (mineral additives) within the cement shall be identified; the dosage of steel slag powder shall be determined through comprehensive testing;

b) Sand and coarse aggregate shall comply with the provisions of GB/T 14684 and GB/T 14685, respectively;

c) Other mineral admixtures such as fly ash, ground granulated blast-furnace slag powder, silica fume, zeolite powder shall comply with the provisions of GB/T 1596, GB/T 18046, GB/T 18736, JG/T 3048, or GB/T 51003, respectively;

d) Concrete admixtures shall comply with the provisions of GB 8076, GB 50119, GB 23439, JC 475, etc.;

e) Mixing water shall comply with the provisions of JGJ 63.

5.3.2 The dosage of steel slag powder shall comply with the provisions of GB/T 51003; the dosage of iron and steel slag powder (a mineral admixture composed of steel slag powder and ground granulated blast-furnace slag powder in a specific ratio) shall comply with the provisions of GB/T 50912. When steel slag powder is combined with other mineral admixtures, the dosage shall comply with the provisions of GB/T 51003.

5.3.3 The mix proportion design for concrete containing steel slag powder shall comply with the following provisions.

a) The concrete mix proportion design shall meet the requirements for workability, strength, durability;

b) The concrete mix proportion design shall be carried out in accordance with the relevant provisions of JGJ 55. For concrete with special requirements, the mix proportion design shall also comply with the provisions of relevant current national standards.

5.3.4 The preparation and construction of concrete containing steel slag powder shall comply with the following provisions.

a) The storage, metering, mixing, transportation of concrete raw materials shall comply with the relevant provisions of GB/T 14902;

b) Concrete placement and curing shall comply with the relevant provisions of GB 50666.

5.3.5 The quality inspection and acceptance of concrete incorporating steel slag powder shall comply with the following provisions.

a) The items for exit-factory and delivery inspection, sampling and testing frequency, judgement criteria for the concrete shall comply with the relevant provisions of GB/T 14902.

b) The acceptance of construction quality for the concrete shall comply with the relevant provisions of GB 50204.

5.4 Mortar

5.4.1 Other raw materials used for mortar shall comply with the provisions of GB/T 25181.

5.4.2 Steel slag powder may be used to prepare masonry mortar, plastering mortar, flooring mortar, ordinary waterproof mortar; when used for other types of mortar, it shall comply with the requirements of current relevant national standards.

5.4.3 The dosage of steel slag powder in mortar shall be determined, through systematic testing based on factors such as mortar type, intended use, environmental conditions, strength grade.

5.4.4 The properties of mortar incorporating steel slag powder shall comply with the provisions of GB/T 25181; the performance test methods shall be carried out in accordance with the provisions of JGJ/T 70.

5.4.5 The preparation and construction of mortar shall comply with the following provisions.

a) The preparation of mortar shall comply with the relevant provisions of GB/T 25181;

b) Exit-factory packaging, storage, transportation of mortar shall comply with the relevant provisions of GB/T 25181;

c) On-site storage and mixing of mortar shall comply with the relevant provisions of JGJ/T 223;

d) Mortar construction shall comply with the relevant provisions of JGJ/T 223.

5.4.6 The quality inspection and acceptance of mortar incorporating steel slag powder shall comply with the following provisions.

a) Type inspection items, exit-factory and delivery inspection items, sampling and group-batching, judgement criteria shall comply with the relevant provisions of GB/T 25181;

b) On-site inspection items, inspection batch sizes, judgement criteria shall comply with the relevant provisions of JGJ/T 223;

c) Construction and quality acceptance shall be carried out in accordance with the provisions of JGJ/T 223; it shall comply with the provisions of current relevant national standards.

5.5 Bricks and blocks

5.5.1 Steel slag powder may be used to produce concrete bricks and small concrete hollow blocks for construction projects. When used for bricks and blocks intended for water conservancy, municipal, or transportation projects, they shall comply with the relevant provisions of current national standards.

5.5.2 The dosage of steel slag powder shall be determined, through systematic testing based on the strength grade, density grade, or other performance requirements of the bricks or blocks. […]