10. Durability Test

Durability test results for air entrained concrete samples after 200 cycles freezing and thawing:

(1 cycle= 4 hours at -20◦c in the freezer and 4 hours at + 20◦c in the curing tank water).

10.1. Compressive Strength

Table [22]. Test results of the compressive strength for air entrained concrete samples, where was measured after periods of maturation in tank water as a control samples (witness) and compressive strength of samples after 200 cycles freezing and thawing

Tablica [22]

 

Compr. strength after 200 cykles

Freezing & Thawing

Average.

Control

Compr. strength

Average

Loss in strength

W/C

GGBS

 

1

2

3

strength

1

2

3

strength

%

%

%

A – 1

39.4

41.2

38.5

39.7

43.1

39.9

41.2

41.4

4.1

 

0

A – 2

42.6

42.3

41.7

42.2

44.3

43.6

45.8

44.6

5.4

0.45

30

A – 3

43.1

40.8

41.3

41.7

45.9

45.0

43.8

44.9

7.1

 

50

A – 4

37.4

36.1

34.9

36.1

39.3

40.4

39.7

39.8

9.3

 

70

Graph (15) – Research results of compressive strength for aerated concrete samples after 200 cycles of freezing and thawing

The results have shown that, the increase in compressive strength for air aerated concrete samples containing GGBS (39.8÷ 44.6N), where was measured after periods of ripining in tank water as a control samples is significant.

We noteced a clearly decrease in compressive strength in all samples mixes after 200 cycles freezing and thawing.

Graph (16) – Research results of the decrease in compressive strength [%] for aerated concrete samples after 200 cycles of freezing and thawing.

The results showed after 200 cycles freezing and thawing that, less decrease in compressive strength in air entrained concrete samples with 100% CEMII/A-L the decrease was (4.1%) and more decrease in the samples containing GGBS (5.4 ÷ 9.3 %).

Graph (17) – Research results of the decrease in compressive strength [%] for aerated concrete samples after 200 cycles of freezing and thawing

The results showed after 200 cycles freezing and thawing that, less decrease in compressive strength in concrete samples with 100% CEMII/A-L the decrease was (1.7N) and more decrease in samples containing GGBS (2.4 ÷ 3.7 N).

10.2. compressive strength of control (witness) samples

Summary – Compression Strength – Control (witness) Samples

Table [23]. Test results of the air entrained control sample compressive strength, where was measured after periods of maturation in tank water

Tablica [23].

W/C = 0.45

CEM II

CEM II/GGBS

CEM II/GGBS

CEM II/GGBS

Cement content %

100

70/30

50/50

30/70

Compressive strength of control (witness) samples

[N/mm2]]

41.4

44.6

44.9

39.8

Graph(18) – Research test results of the control (witness) compression strength for air entrained concrete samples

The results showed that, the increase in air entrained concrete compressive strength of control mixes (witnesses) containing 30% and 50% GGBS was significantly higher than other concrete made with 100% CEM II/A-L where was (41.4N).

The highest compressive strength in the control mixes was the samples containing 50% GGBS (44.9N).

10.3. Summary – Durability Test – under the influence of compressive Strength

Table [24]

W/C = 0.45

CEM II

CEM II/GGBS CEM II/GGBS CEM II/GGBS

Cement Content %

100

70/30

50/50

30/70

Compressive strength after 120 day maturated in water

[N/mm2]]

41.4

44.3

43.8

39.1

Compressive strength of

Control Samples

[N/mm2]]

41.4

44.6

44.9

39.8

Compressive strength after 200 cycles

Freezing & Thawing

[N/mm2]

39.7

42.2

41.7

36.1

Loss in Compressive strength in

[%]

4.1

5.4

7.1

9.3

Loss in Compression strength in

[N]

1.7

2.4

3.2

3.7

10.4. Durability Test – Mass Loss of concrete samples:

Table [25]. Test results of loss of mass for air entrained concrete samples before and after the test, after 200 cycles of freezing and thawing

Table [25]

 

 

Mass of samples after 200 cykles

Freezing & Thawing

Averag of

Mass of samples before test

Average

of

Loss

In

mass

W/C

GGBS

 

1

2

3

mass

1

2

3

masa

%

%

%

A – 1

2428

2421

2424

2424

2430

2425

2426

2427

0.12

 

0

A – 2

2420

2426

2418

2421

2426

2429

2424

2426

0.21

0.45

30

A -3

2417

2410

2414

2414

2428

2419

2423

2423

0.37

 

50

A – 4

2405

2416

2400

2407

2421

2425

2416

2421

0.58

 

70

Graph (19) – Research results of the loss in mass in [g] for aerated concrete samples after 200 cycles of freezing and thawing

The results have shown for aerated concrete samples after 200 cycles freezing and thawing that, the loss in mass was only (3g) for 100% CEMII/A-L, and for samples containing GGBS the loss of mass was between (5÷14g).

Graph (20) – Research results of the loss in mass in [%] for aerated concrete samples after 200 cycles of freezing and thawing

The results have shown for aerated concrete samples after 200 cycles freezing and thawing that, the loss in mass was only (0.12%) for samples 100% CEMII/A-L, and for samples containing GGBS was the loss of mass between (0.21÷0.58%).

10.5. Summary – Durability Test – under the influence of mass loss:

Table [26]

Air entrained Concrete

Loss of mass

W/C = 0.45

Cement content %

100% Cem-II

30% GGBS

50% GGBS

70% GGBS

Mass of samples before test

[g]

2427

2426

2423

2421

Mass of samples after 200 cycles

[g]

2424

2421

2414

2407

Loss in mass after 200 cycles

[g]

3

5

9

14

Loss in mass after 200 cycles

[%]

0.12

0.21

0.37

0.58

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

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