24 months mortar test

on Saint-Astier® NHL

Note: performance figures will vary using different sands.
For example see figures on NHL 3.5 tested using a 3mm – 0.075 well graded common sand (Doyeaux).

Test on NHL/sand mixes (1:2 - 1:2.5 - 1:3)

1:2
1:2.5
1:3


Norm/method used for test
NHL 5
NHL 3.5
NHL 2
NHL 5
NHL 3.5
NHL 3.5
NHL 2
NHL 5
NHL 3.5
NHL 2
Doyeaux sand
Water content gr.
225
226
228
215
220
250
214
208
211
206
Water/binder ratio
0.67
0.88
1.07
0.79
1.07
1.21
1.27
0.92
1.23
1.47
Penetration mm
8
9.5
11
7.5
9
10
8.5
7
8.5
9.5
EN459-2 P.5.5.3
Set (beginning) h
4.3
5.3
8 3/4
3.3
6
6.15
9
3
6
9.3
EN196.2 P.6.2
Bulk density kg/m3 (no curing)
2110
2110
2100
2115
2140
1975
2080
2105
2110
2100
EN459.2 P.5.8
Air content %
0
1.6
2
0
0
0
1
0
3
2
EN459.2 P.5.7
Elast. Moduli Mpa
28 days
10800
9010
9025
11000
9000
8600
9800
10000
8970
9000


French Std on one coat renders
6 months
18000
16250
12600
17050
13505
12050
12030
16900
12450
11800
12 months
18510
15280
12515
17280
13620
12030
16150
13150
11900
24 months
21500
17480
13375
18020
13785
12000
17540
13670
11750
Flexural Strength Mpa
EN459.2
7 days
0.53
0.43
0.28
0.38
0.31
0.28
0.31
0.4
0.28
0.25
28 days
0.9
0.73
0.74
0.8
0.48
0.45
0.73
0.66
0.65
0.72
6 months
2.2
2.18
1.28
1.75
1.7
1.3
1.2
1.55
1.38
1.08
12 months
2.4
2.25
1.3
2.2
2.05
1.25
1.8
1.5
1.05
24 months
2.51
2.6
1.41
2.3
2
1.15
2.05
1.53
1.05
Compressive Strength MPa
EN459-2 P.5.1
7 days
1.96
0.75
0.62
1
0.57
0.5
0.53
0.88
0.53
0.47
28 days
2.2
1.88
1.48
2
1.47
1.3
1.36
1.5
1.34
1.25
6 months
7.31
7.1
3.84
5.91
5.34
4.02
3
5.31
3.94
2.88
12 months
9.28
7.5
4
8.44
5.9
2.9
6.5
3.9
2.9
24 months
10.81
8.63
4.25
8.81
6
3
7.8
3.97
2.75


Fr. Std. for one coat renders
Permeability at compl. carb gr. of air/m2 x hour x mmHg
0.55
0.64
0.68
0.5
0.65
0.71
0.52
0.72
0.71
Shrinkage at 28 days mm.m
0.17
0.59
0.75
0.13
0.44
0.6
0.15
0.25
0.51
Water absorption l/hxm 2
3
4.5
10.5
3.2
7.3
12.1
5.5
9.4
15.4
at compl. Carbonation
Capillarity gr/cm2 xmin1/2
0.88
1.18
3.05
2.54
4.7
7.84
4.61
6.3
8.7
at compl. Carbonation

Test on NHL/putty lime blends (at 10% - 30% - 50%)

NHL 5/Putty/Sand NHL 3.5/Putty/Sand Test Norm/method\A0used
Blend ratio
0.9/0.1/3
0.7/0.3/3
0.5/0.5/3
0.9/0.1/3
0.7/0.3/3
0.5/0.5/3
Water/binder ratio gr
1.2
1.07
1.03
1.04
1
0.95
Penetration mm
7
10
11
8
12
13
EN459-2 P.5.5.3
Set (beginning) h
3.5
5.25
9.5
6.5
8.5
10
EN196-2 P.5.8
Bulk density kg/m3 (no curing)
2105
2040
2030
2070
2040
2020
EN459-2 P.5.8
Air content %
0
0
3
3
4
6
EN 459-2 P. 5.7
Elast. Moduli Mpa
28 days
11000
10020
8000
8400
8050
7510


French Std on one coat renders
6 months
16000
14000
13000
13200
12600
11000
12 months
16510
14320
13020
13410
12900
11050
24 months
16500
13950
13220
14520
13010
10850
Flexural Strength N/mm2
7 days
0.4
0.35
0.32
0.38
0.5
0.26
AN459.2
28 days
0.67
0.65
0.45
0.6
0.52
0.38
6 months
1.15
1.13
0.83
1.33
1.05
0.65
12 months
1.75
1.15
0.85
1.5
1.2
0.8
24 months
1.55
1.2
0.8
1.56
1.26
0.84
Compressive Strength N/mm2
7 days
0.82
0.66
0.42
0.76
0.76
0.22
EN459-2 P.5.1
28 days
1.4
1.1
0.6
1.3
1.1
0.75
6 months
4.8
3.95
2.97
3.9
3.63
2
24 months
5.25
4.31
2.85
4.75
4.55
2.65
Permeability at complete Carb (vapour exchange) gr of air\A0 x m2 x hour x mmHg
0.6
0.59
0.63
0.69
0.71
0.68



Fr. Std on one coat renders
Shrinkage at 28 days mm/m
0.25
0.6
0.84
0.35
0.67
0.89
Water absorption l/hxm2 at compl. Carbonation
10
12.3
18
11.2
15.6
19.3
Capillarity gr/cm2 xmin1/2at compl. Carbonation
4.41
8.72
12.94
9.95
10.2
13.75

Cement, hydrated lime and sand (1:1:6 - 1:2:9)

Blends 1:1:6 1:2:9 Norm/method used for test
Water content gr.
200
200
Water/binder ratio
0.72
0.65
Penetration mm
7
7
EN459-2\A0P.5.5.3
Set (beginning) h
1.3
1
Bulk density (no curing) kg/m3
2100
2100
EN459-2 P.5.8
Air content %
0
0
EN459-2 P.5.7
Elast. Moduli Mpa


French Std. for one coat renders
28 days
16200
15595
6 months
22010
19300
EN459-2
12 months
22210
19700
24 months
22150
19650
Flexural Strength N/mm2
7 days
2.05
1.65
28 days
1.95
1.55
EN459-2\A0P.5.1
6 months
2.1
1.5
12 months
2.2
1.7
24 months
2.2
1.75
Compressive Strength N/mm2
7 days
5.02
4.96
28 days
7.7
5.56
6 months
8.1
5.75
12 months
8.7
6.05
24 months
8.5
5.95
Permeability (Vapour exch) gr of air x m2 x hour x mmHg
0.23
0.25




At complete carbonation French Std. for one coat renders
Shrinkage at 28 days mm/m
0.63
0.42
Water absorption l/hxm 2 at compl. Carbonation
0.23
0.25
Capillarity gr/cm2 xmin1/2
1.08
6.86

The proposed EU norms are conducted on mortars prepared with a binder/sand ratio of approx. 1:1.3. and Standard EU laboratory sand (ISO 679).

The tests reflect the performance of mortars made with the same sand but with volumetric mixes that are commonly used.

Proctors air cured have been stored at constant 15°C and 95% humidity.

Water addition was made to obtain the same workability on all mortars.

Notes
Compressive strenght in NHL mortars is achieved gradually, allowing for movement.
This is due to the lack of cement. In cementitious mixes the hardening is much faster and mostly complete within 28 days.

Elasticity, which is so important to achieve joint free construction, is by far better in NHL mortars than cementitious mixes.

Shrinkage, capillarity and vapour exchange (permeability to air) also show better values than cementitious mixes.

The test on NHL/putty blends shows the significant performance alteration that takes place Although this does not signify that these blends cannot be used, we think that the specifier should be aware of the related performance.

The initial set up of these test was done in consultation with:
– Mrs. J. M. Teutonico of English Heritage, Mrs. P. Gibbons of The Scottish Lime Centre,
– Prof. John Ashurst and Douglas Johnston to whom we are grateful for their co-operation and suggestions.