11. Conclusions of the study

Based on the survey and the results it can be concluded that:

– Concretes made using 100% CEMII/A-L and concretes made with the addition of ground slag in quantities (30%, 50%, 70%) met the requirements of PN-88 / B-06250 for the degree of frost resistance F200.

– The results from compressive strength and loss in mass indicate that all concrete mixes with air entrainment showed better freezing and thawing resistance than without air entrainment.

The air entrainment in concrete mixes was a rate of 4.6÷5.5% and this is in accordance with the requirements of BS EN 206-1 [4] for the composition of concrete exposed to frost aggression (exposure class XF), where one of the conditions required is minimal degree of aeration concrete ≥ 4%.

– Concrete made using the additive ground slag showed inferior resistance to frost compared to tests of concretes made from 100% CEMII/A-L.

– The increase in concrete compressive strength after 120 days of ripening in curing tank water with added GGBS was significantly higher than other concretes made with cement 100% CEM II/A-L.

– The increase in control concrete compressive strength with 50% of GGBS was significantly higher than other concrete made with 100% CEM II/A-L Tab.(14, 15).

–  Determination of mass loss of samples subjected to 200 cycles of freezing the weight of the witnesses indicated that the requirements of PN-B-06250 (loss in weight ≤ 5%) were achieved in all tested concretes made with cement CEM II/A-L and with addition of ground slag (ggbs) in amounts (30%, 50%, 70%). Tab. (17, 26)

From my experience I can confirm that, if the level of compressive strength of concrete containing additives granulated blast furnace slag (GGBS) after frost resistance test meets the specific class of concrete compressive strength, the concrete samples did not show any cracks, and the loss of the mass is consistent with the standard, then we can conclude the concrete as resistant to frost.

Professor Pawel Lukowski. Head of the Department of Building Materials Engineering. Warsaw University of Technology

Dr. Eng. Joanna Julia Sokolowska. Department of Building Materials Engineering. Warsaw University of Technology

MSc. Eng. Ali Salih Technical and Quality Manager – Casey Concrete, Gorey Co. Wexford


Part I – DURABILITY OF CONCRETE CONTAINING GGBS IN EXPOSED TO FREEZING AND THAWING CONDITIONS

1- Abstract 2. Background 3. Prisms analysis of cement samples (MORTARS) 4. Test results of the Prisms 5. Test on Without Air Entrained concrete samples: 6. Strength test results 7. Durability Test

Part II – DURABILITY OF CONCRETE CONTAINING GGBS IN EXPOSED TO FREEZING AND THAWING CONDITIONS

8. Air Entrained Concrete 9. Strength test results of the air entrained concrete samples maturated in tank water 10. Durability Test 11. Conclusions of the study/a> 12. Literature

Top