For a defined fine mortar quantity, fines content and w/c-ratio, the quantity of fines can be established in dependence of the durability requirements. � Physical demands of the concrete (compressive strength, flexural tension, early strength) � Demands on durability (e.g. impermeability, sulfate resistance, AAR) � Demands on processing (structure of fines, granular form and reactivity) � Local and regional availability (especially for sand and binders) � Costs (material costs and transport costs) � Transport distances � Sustainability due to type of material, processing or transport of components The proper fine mortar quantity If it is true that the cement content does not play a role in achievement of the required strength (Abram’s), then the necessary or correct quantity of cement must be established via other criteria: � Achievement of the planned concrete processing (fines content and cement paste) � Achievement of required durability properties (resistance to external influences)
0.80
w/c-ratio
0.65 0.60 0.55 0.50 0.45
Self-Compacting Concrete
0.70
Pumped Concrete
„Crane & Bucket“ Concrete
0.75
Binder content [kg/m3] 200 300 400 500 600 700
0.40
250 350 450 550 650 750
0.35 200
225
250
275
300
325
350
375
400
425
450
475
Fine Mortar Paste [L/m ] 3
500
525 550 575 Binder Paste [L/m3]
Sieve curve with low sand content
225
249
273
292
321
345
370
394
418
442
466
490
515
539
568
592
240
253
286
319
332
355
380
404
428
452
476
500
525
349
573
597
Sieve curve with high sand content
Fig. 4.2.1: Relation between concrete compressive strengths of a specific cement, expressed in w/c-ratio, and the fine mortar quantity (L/m³) for a required cement content (kg/m3)
45
Mix Design
4. Concrete Mix Design