The Contractor shall not change the source and/or the formulation of the binder and the mix proportions of the concrete, unless they have been tested and approved by the Superintendent. 820.27 DURABILITY The intent of this Specification is to provide durable concrete in the permanent works. Durability requirements comply with AS5100.5 unless noted otherwise in this specification. 820.28 CLASS OF CONCRETE FOR MIX DESIGN All concrete for the Works shall be as specified in Table 820.2 except that blinding concrete and make-up concrete shall be Class N20 in accordance with AS 1379. Type GP or GB cement only be used in all classes of concrete HOLD except for class S50M. Type LH cement may be used for elements greater than 500 mm thick. Class S50M concrete shall use blended cement consisting of 32% Type GP cement, 60% ground granulated iron blast-furnace slag and 8% silica fume. The combined grading shall be within the limits given in Figures 820.1, 820.2 or 820.3 after making allowance for the permissible tolerances on individual aggregate grading specified in Clause 820.08. Subject to the superintendent’s approval, the contractor may submit a Concrete combined grading curve for mixes supplied in remote locations in lieu of the Supply in grading limits shown in Figures 820.1 and 820.2. The percentage passing Remote of 0.075 mm and 0.15 mm sieves shall not exceed 2% and 3% Locations respectively. The grading of material can vary from coarse to fine in a uniform and consistent manner. FIGURE 820.1 AGGREGATE GRADING ENVELOPE 20mm FIGURE 820.2 AGGREGATE GRADING ENVELOPE 14mm
The Contractor shall not change the source and/or the formulation of the binder and the mix proportions of the concrete, unless they have been tested and approved by the Superintendent. 820.27 DURABILITY The intent of this Specification is to provide durable concrete in the permanent works. Durability requirements comply with AS5100.5 unless noted otherwise in this specification. 820.28 CLASS OF CONCRETE FOR MIX DESIGN All concrete for the Works shall be as specified in Table 820.2 except that blinding concrete and make-up concrete shall be Class N20 in accordance with AS 1379. Type GP or GB cement only be used in all classes of concrete except for class S50M. Type LH cement may be used for elements greater than 500 mm thick. HOLD Class S50M concrete shall use blended cement consisting of 32% Type GP cement, 60% ground granulated iron blast-furnace slag and 8% silica fume. The combined grading shall be within the limits given in Figures 820.1, 820.2 or 820.3 after making allowance for the permissible tolerances on individual aggregate grading specified in Clause 820.08. Subject to the superintendent’s approval, the contractor may submit a combined grading curve for mixes supplied in remote locations in lieu of the grading limits shown in Figures 820.1 and 820.2. The percentage passing of 0.075 mm and 0.15 mm sieves shall not exceed 2% and 3% respectively. The grading of material can vary from coarse to fine in a uniform and consistent manner. Concrete Supply in Remote Locations FIGURE 820.1 AGGREGATE GRADING ENVELOPE 20mm FIGURE 820.2 AGGREGATE GRADING ENVELOPE 14mm