Development of Draft Protocol for Testing of Structural Components and Systems
(a joint initiative of MoHUPA under technology submission of Pradhan Mantri Awas Yojna & IIT, KANPUR)
Portland pozzolana Cement-Fly Ash Based
The Portland Pozzolana Cement is a kind of Blended Cement which is produced by either inter-grinding of OPC clinker along with gypsum and pozzolanic materials in certain proportions or grinding the OPC clinker, gypsum and Pozzolanic materials separately and thoroughly blending them in certain proportions. Pozzolana such as fly ash is essentially a siliceous material which while in itself possessing little or no cementitious properties will, in finely divided form and in the presence of water, react with calcium hydroxide at ambient temperature to form compounds possessing cementitious properties. The manufacture, physical and chemical requirements of Portland pozzolana cement using only fly ash pozzolana shall conform to the IS: 1489-1 (1991) as given below. .
- Raw Materials:
- Pozzolana: Fly ash used in the manufacture of Portland-pozzolana cement shall conform to IS 3812: 1981
- Portland Cement Clinker: The Portland cement clinker used in the manufacture of Portland-pozzolana cement shall comply in all respects with the chemical requirements of IS 269: 1989
- Portland Cement: Portland cement for blending with fly ash shall conform to IS 269: 1989
- Other admixtures: Not more than 1 percent may be added
- Manufacture: Portland-pozzolana cement shall be manufactured either by intimately inter-grinding Portland cement clinker and fly ash or by intimately and uniformly blending Portland cement and fine fly ash. The fly ash constituent shall not be less than 10 percent and not more than 25 percent by mass of Portland-pozzolana cement.
- Chemical Requirements: Portland-pozzolana cement, shall comply with the chemical requirements given in Table 1
- Physical Requirements:
- Fineness: When tested by the air permeability method described in IS 4031 (Part 2): 1988, the specific surface of Portland-pozzolana cement shall be not less than 300 m2/kg.
- Soundness: When tested by ‘Le Chatelier’ method and autoclave test described in IS 4031 (Part 3): 1988, unaerated Portland-pozzolana cement The average drying shrinkage of mortar bars shall not have an expansion of more than 10 mm and 0.8 percent respectively.
- Setting Time: The setting time of Portland-pozzolana cement, when tested by the Vicat apparatus method described in IS 4031 (Part 5): 1988, shall be 30min (Minimum) for initial setting time and 600min (Maximum) for final setting time
- Compressive strength: The average compressive strength tested in the manner as described in IS 4031 (Part 6): 1988 shall be as follows:
At 72 ±1hr                 16 MPa, Min
At 168 ± 2hrs             22 MPa, Min
At 672 ±4hrs             33 MPa, Min
- Drying shrinkage: The average drying shrinkage of mortar bars prepared and tested in accordance with IS 4031 (Part 10): 1988 shall not be more than 0.15 percent.