The petrographic analysis of the natural building stones...

37

3.1.2.The Petrographic Analysis of the Natural Building Stones, Bricks and the Mortars

Stone 1 ; The sample is a microcrystalline limestone which contains 99 % micrites and

cryptocrystalline carbonate mud, and, 1% opaque ironoxide (Fe2O3) minerals. The pellets,

indicates the ripple medium, and the size differentiated particle zonning and pseudo oolites were

observed in the thin section, Figure 3.44.

Stone 2 ; The sample is similar with stone 1. It additionally has 1 % quartz, 1-2 % opaque iron

oxide minerals and 1-2 % pores, Figure 3.45.

Stone 3 ; The sample is a microcrystalline limestone that contains calcites with

cryptocrystalline-microcrystalline size, 1-2 % of opaque minerals, and, large amount pores. Most

of the pores were filled with the secondary calcite minerals and lesser amount of the pores were

filled with secondary clay and chlorite minerals, Figure 3.46a, Figure 3.46b.

Stone 4 ; The sample is a microcrystalline limestone which contains 99 % micrites and

cryptocrystalline carbonate mud, and, 1% opaque ironoxide (Fe2O3) minerals. The pellets,

indicates the ripple medium, and the size differentiated particle zonning and pseudo oolites were

observed in the thin section, Figure 3.44.

Stone 5 ; The sample is a fossiliferous microcrystalline limestone that contains 70 % of micrites

and fossils. Approximately 30 % of the secondary large calcite crystals formed in the pores of

the mass, and, at the boundaries and inside of the shell fragments, Figure 3.47.

Stone 6 ; The sample is a marble that contains mainly calcite and seldom dolomite crystals. The

sizes of calcite crystals ranged in 0.1-2.0 mm and cumulated between 0.1-0.6 mm. The sizes of

the dolomite crystals were even smaller than the calcite crystals, Figure 3.48.

Stone 7 ; The sample is a cryptocrystalline calcitic and fossiliferous microcrystalline limestone.

The secondary large calcite crystals which different from the calcite binder, at the pores and at

the boundaries of the fossils. The sample contains 1 % chlorite and iron oxide spots at the

boundaries of the shell fragments, and, 1 % opaque minerals, Figure 3.49.

Stone 8 ; The sample is a fossiliferous microcrystalline limestone with excessive amount of

fossils. It has also another amorphous zones with excessive amount of fossils and some stone

particles (limestone particles with and without clay and sand, altered granite particles), feldspar

(orthoclase) and quartz in an organic binder. The stone totally has 2 % of opaque minerals,

Figure 3.50, Figure 3.51, Figure 3.52, Figure 3.53.

Stone 9 ; The sample is a limestone that contains microcrystalline calcite, lesser amount shell

fragments, 0.5-1 % opaque minerals, and, 3-5 % pores. The calcite crystals in the sample were

well crystallized, homogenously distributed, and, had no alteration. The sizes of these calcite

crystals were below 0.3 mm, Figure 3.54.

Stone 10 ; The sample is a microcrystalline limestone that contains calcites with

cryptocrystalline-microcrystalline size, 1-2 % of opaque minerals, and, large amount pores. Most

of the pores were filled with the secondary calcite minerals and lesser amount of the pores were

filled with secondary clay and chlorite minerals.

38

Brick 1 ; The brick sample has 15 % stone and mineral particles. Most of the particles with the

sizes smaller than 0.1 mm were quartz and feldspar minerals. A few ones having the sizes

around 0.5 mm were quartz, partly altered feldspar, mica minerals and limestone particles,

Figure 3.55, Figure 3.56, Figure 3.57.

Brick 2 ; The brick sample has 25 % of stone particles and minerals in the whole thin section 75

% is the clay. The stone particles, which are smaller than 0.5 mm, except a few 2.0 mm sized,

ones were cryptocrystalline and microcrystalline limestone, granite and quartzite. Only some of

the limestone particles and the feldspars partly altered. The minerals were orthoclase,

plagioclase, quartz and very few amphiboles such as hornblende, Figure 3.58.

Brick 3 ; The brick sample has mostly granitic stone particles and lesser amounts of quartzite,

limestone and sandy limestone particles. The minerals were orthoclase, quartz and a few partly

altered muscovite.

Brick 4 ; The brick sample has similar properties with brick 2 sample. It has mostly granitic

particles and lesser amounts of quartzite, limestone and sandy limestone particles. The minerals

of the brick were quartz, a few muscovite and partially altered orthoclase, Figure 3.59, Figure

3.60.

Brick 5 ; The brick sample has 20-22 % stone particles and minerals, 3 % opaque minerals,

and, a few pores. The sizes of the stone particles were mostly cumulated in between 0.5-2.0 mm

were granite, gneiss granite, quartzite, and sandstones with and without clay and carbonate

inclusions. Most of the particles are smaller than 0.5 mm and only a few alkaline feldspar

particles were around 3.0 mm. All of the types of the particles, except the quartzite were mostly

or partially altered. The minerals were mostly orthoclase and a lesser amounts of plagioclase,

Figure 3.61.

Brick 6 ; The brick sample has 20-25 % stone particles, 2-3 % of opaque minerals and very little

amount pores in the binder (72-78 %). The sizes of the stone particles were mostly between 0.3-

1.8 mm, they were granite, gneiss granite, quartzite, sandstone, sandy limestone and a few

igneous stone particles. All the types of the particles, except quartzite were mostly or partially

altered. Most of the particles were smaller than 0.3 mm. A few alkaline feldspars around 5.0

mm were also observed in the sample. Most of the minerals were partially altered orthoclase and

lesser amounts of quartz and plagioclase, Figure 3.62, Figure 3.63.

Figure 3.44. The micritic limestone with Figure 3.45. The micritic limestone which

pseudo oolithes, (Stone 1 and 4) contains large calcite crystals, (Stone 2)

39

Figure 3.46a. Smaller calcite and opaque minerals (single nicole), (b) Double nicole,

(Stone 3)

Figure 3.47. The cryptocrystalline fossiliferous Figure 3.48. The large calcite crystals in

limestone with micrites and secondary calcites, marble, (Stone 6)

(Stone 5)

Figure 3.49. A limestone with micrites and Figure 3.50. The limestone particle with

recrystallized part, (Stone 7) numilite fossils, (Stone 8)

40

Figure 3.51. A different numilite fossil, Figure 3.52. The limestone, fossil, and,

(Stone 8) sound and altered orthoclase particles,

(Stone 8)

Figure 3.53. The rounded limestone particle, Figure 3.54. The tough calcite crystals and

(Stone 8) opaque minerals, (Stone 9)

Figure 3.55. The quartz and feldspar particles Figure 3.56. The slightly altered feldspar

in clay matrix, (Brick 1) particle, (Brick 1)

41

Figure 3.57. The altered orthoclase particle, Figure 3.58. Feldspar particle which is

(Brick 1) mostly altered, (Brick 2)

Figure 3.59. Partly altered alkaline orthoclase Figure 3.60. On light, (Brick 4)

(off light), (Brick 4)

Figure 3.61. The plagioclase mineral altered Figure 3.62. Sound and altered plagioclases

at the firing process, (Brick 5). (the black material can be hematite formation),

(Brick 6)

Figure 3.63. The feldspars as plagioclase, and opaque minerals as iron oxide, (Brick 6)

42

Figure 3.64. Altered F particle size with Figure 3.65. The slightly altered quartzite

~250µ is in the binder, (Mortar 1) particle with approximately ~250µ size,

(Mortar 2)

Figure 3.66. The phase between the brick Figure 3.67. The brick dusts and black

piece and binder and the feldspar particles particles (probably magnetite or hematite)

in the lime paste, (Mortar 2) in the binder, (Mortar 3)

Figure 3.68. The altered feldspars due to Figure 3.69. The phase between the binder

carbonate formation, (Mortar 4) and the feldspar particle, (Mortar 4)

43

Figure 3.70. The calcerous fossil, (Mortar 5) Figure 3.71. The phase between binder and

quartzite particle, (Mortar 6)

Figure 3.72. The quartz, calcite and calcerious Figure 3.73. The rounded limestone and

Particles in the binder, (Mortar 7) quartz particles, (Mortar 9)

Figure 3.74. The large amount opaque Figure 3.75. The fossil, orthoclase and

(iron oxide) minerals together with quartz, quartz particles in the binder, (Mortar 10)

feldspar and carbonate particles, (Mortar 10)

Figure 3.76. The calcium carbonate particles, (Mortar 11)

44

Figure 3.77. The fossil, the feldspar and the Figure 3.78. The altered feldspar as clay

granite particles, (Mortar 11) formation, (Mortar 12)

Figure 3.79. Feldspar particle totally Figure 3.80. The limestone and the fossils,

transformed to clay and the limestone (Mortar 14)

particles, (Mortar 12)

Figure 3.81. Altered orthoclase as domorite Figure 3.82. The same with Figure 3.81.

formation, (Mortar 16)

Figure 3.83. The limestone and the fossils, (Mortar 17)

45

Table 3.4. Visual and petrographic properties and composition of the mortar samples

Sample

No Century Colour Condition Particles and Minerals * Coarse Aggregates (%)

Approximate

Composition (%)

BP (%) S (%) Binder:BP:S

M1 5th Pink Weak- BP,LS,Mr,Qz,Gr,OrC,Q,Pr 21.02 (10-15 mm) 30-35:30-35:30-35

Century Crumbling 100 0

M2 5th Grey- Sound BP,LS,SS, Q,OrC, Q 32.23 (10-12 mm) 25:50:25

Century White 100 0

M3 Medieval Pink Sound BP,LS,F,Q,OrC 16.48 (12-15 mm) 25:50:25

Age 100 0

M4 Medieval Pinkish Sound BP,LS,Qz,Gr,OrC,Q,B,PC 13.09 (12 mm) 25:50:25

Age White 100 0

M5 Medieval Light Crumbling BP,LS,Qz,OrC,PC 14.33 (13 mm) 15:55-60:25-30

Age Pink 100 0

M6 Medieval Pinkish Sound BP,Qz,LS,OrC,Q 12.19 (15 mm) 25:60:15

Age White 100 0

M7 5th Dark Crumbling BP,LS,Qz,OrC,PC 0 30-35:40-45:25

Century Pink

M8 5th Dark Sound BP,LS,Qz,OrC,PC 0 30:40-45:25

Century Pink

M9 5th Pink Sound BP,LS,M,Qz,Gr,OrC,PC,Q 0 25-30:20-25:50

Century

M10 5th Pink Sound BP,Qz,LS,Q,OrC 17.41 (13 mm) 30:40:30

Century 100 0

M11 5th Light Sound BP,LS,Qz,Gr,OrC,PC,Q 24.62 (15-20 mm) 20-25:40:40

Century Pink 100 0

M12 5th Light Sound BP,LS,Qz,Gr,OrC,PC,Q 12.03 (12-15 mm) 20-25:40:40

Century Pink 75-80 20-25

M13 5th Pink Sound BP,LS,Q,OrC 10.20 (10-12 mm) 25-30:40-45:25-30

Century 100 0

M14 15th Cream Quite LS,Qz,Q,OrC,PC 7.92 (8 mm) 30-35: - :65-70

Century Sound 100 0

M15 Medieval Light Sound BP,Q,LS,OrC 34.4 20-25:70:5-10

Age Pink 100 0

M16 Medieval Pink Sound BP,LS,SS,Gr,OrC 31.04 (12-18 mm) 30:40-45:25-30

Age 100 0

M17 Medieval Pink Sound BP,LS,SS,Gr,OrC 21.03 (7-10 mm) 30:30-35:35-40

Age 100 0

M18 Medieval Grey Quite LS,Qz,Q,PC 45.02 (5 mm) 30-35:3-5:65

Age Sound 0 100

* The amounts are from more to less.

M : Mortar Qz : Quartzite pieces B : Biotite pieces S : Sand particles Q : Quartz pieces PC : Plagioclase pieces SS : Sand stone pieces Gr : Granite pieces LS : Limestone pieces BP : Brick pieces AlF : Alkaline Feldspar pieces Mr : Marl pieces

OrC : Orthoclase pieces Pr : Pyroxine pieces

46

Continued from the table 3.4,

Mortar

Samples Notes

M1 Gel formation was observed around the brick pieces. The feldspars were partially altered.

M2 Adhesion between the binder-brick piece was very good. The gel formation was only

observed around some quartz particles.

M3

Adhesion between the binder-brick pieces was very good while the binder-limestone

pieces adherence was poor. The gel formation was observed around the alkaline feldspars (orthoclase) and quartz particles.

M4

Adhesion between the binder-brick pieces was good. The gel formation was observed

around the brick pieces. There was also some gel formation around some quartz

particles.

M5 Adhesion between the binder-brick pieces and binder-sand particles was poor. Limited

gel formations were observed around the both brick pieces and the sand particles.

M6 Adhesion between the binder-brick pieces and binder-sand particles was poor, clay and gel formations were observed around both the brick pieces and the sand particles.

M7 Adhesion between the binder-brick pieces and binder-sand particles was poor. The gel

formation were observed around both brick pieces and the sand particles.

M8 Same as M7.

M9

Adhesion between the binder-brick pieces and binder-sand particles was poor. The clay and gel formation were observed around both the brick pieces and the sand

particles.

M10

Adhesion between the binder-brick pieces was good and there was partial gel formation while binder-sand particles adherence was poor. There were partially

siliceous, sericite and carbonate formation alterations behind the partial gel formation.

M11 Adhesion between the binder-brick pieces and binder-sand particles were good.

Orthoclases were partially altered.

M12 All properties were similar to the M11, except M12 contains less limestone pieces in a

small amount.

M13

Adhesion between the binder-brick pieces was good, binder-sand particles adherence

was poor. Partial gel formation was observed around both brick pieces and the sand particles. Orthoclases were partially altered.

M14 Sample has partially yellow spots. Plagioclases were partially altered.

M15 Binder-brick pieces adherence was good, binder-sand particles adherence was poor.

Orthoclases were partially altered.

M16

Adhesion betwwen the binder-brick pieces and the binder-sand particles was good.

Partial gel formation was observed around the brick pieces. Orthoclases were partially

altered.

M17 All properties were similar to the M16 except crushed brick : sand ratio was different.

M18 Adhesion between the binder-sand particles and the binder-brick piece was good.

Some fossiliferous limestone pieces and plagioclases were partially altered.

47

Table 3.5. The sieve analysis and the grading of the aggregates (%) of the mortar samples

Sample Acid Coarse Aggregates (8 - 1mm) %

Approximate ratios (8 - 4mm) %

of the 1-8 mm agg.

(4 -1mm) % (1 - 0,125 mm) %

Remains

%

No Insolubles

(%) BP (%) S (%) BP (%) S (%)

BP (%)

Coarses

S(%)

Coarses

BP (%)

Medium

S (%)

Medium

BP (%)

Fines

S (%)

Fines ( > 0,125)

M1 56.4 21.02 (10-15 mm) 54.26 20 (4-7 mm) 80 (1-4 mm) 21.5 3.23

5thC 100 0 45-50 50-55 100 0 30-35 65-70 30-35 65-70

M2 52.95 32.23 (10-12 mm) 55.83 60-65 (4-8mm) 25-40 (1-4 mm) 9.55 2.39

5thC 100 0 60 40 100 0 50 50 75-80 20-25

M3 49.41 16.48 (12-15 mm) 66.94 60 (4-8 mm) 40 (1-4 mm) 12.74 3.83

Med 100 0 80 20 100 0 60 40 30-35 65-70

M4 57.28 13.09 (12 mm) 67.79 60 (4-10 mm) 40 (1-4 mm) 15.76 3.36

Med 100 0 80 20 100 0 55-60 40-45 30-35 65-70

M5 50.11 14.33 (13 mm) 63.76 45-50 (4-10 mm) 50-55 (1-4 mm) 16.88 5.03

Med 100 0 65 35 100 0 30-40 60-70 40-50 50-60

M6 47.87 12.19 (15 mm) 66.37 40 (4-10 mm) 60 (1-4 mm) 14.46 6.98

Med 100 0 80 20 100 0 65 35 50 50

M7 39.47 0 57.33 60 (4-10 mm) 40 (1-4 mm) 34.94 7.73

5thC 80 20 95 5 30 70 40-45 55-60

M8 52.75 0 65.5 40 (4-12 mm) 60 (1-4 mm) 28.47 6.04

5thC 50 50 95 5 20-25 75-80 25 75

M9 38.71 0 51.82 30-35 (4-8 mm) 65-70 (1-4 mm) 42.39 5.80

Med 35 65 85 15 15-20 80-85 30 70

M10 65.62 17.41 (13 mm) 48.94 75 (4-8 mm) 25 (1-4 mm) 31.32 2.33

5thC 100 0 40 60 50 50 35 65 15 85

M11 56.33 24.62 (15-20 mm) 54,09 25-30 (4-9 mm) 70-75 (1-4 mm) 18.28 3.01

5thC 100 0 50 50 50 50 50 50 50 50

M12 64.93 12.03 (12-15 mm) 51 40 (4-8 mm) 60 (1-4 mm) 32.83 4.14

5thC 75-80 20-25 40-45 55-60 40-45 55-60 40-45 55-60 30-35 65-70

M13 43.11 10.20 (10-12 mm) 47.12 25 (4-8 mm) 75 (1-4 mm) 36.72 5.97

5thC 100 0 50 50 50 50 50 50 50 50

M14 11.39 7.92 (8 mm) 13.77 15 (4-8 mm) 85 (1-4 mm) 67.67 10.65

15thC 100 0 5-8 92-95 5-8 92-95 100 0 0 100

M15 54.19 34.4 (13 mm) 53.4 45-50 (4-7 mm) 50-55 (1-4 mm) 9.94 2.27

Med 100 0 85-90 10-15 85-90 10-15 85-90 10-15 30 70

M16 59.84 31.04 (12-18 mm) 52.95 20-25 (4-8 mm) 75-80 (1-4 mm) 13.62 2.39

Med 100 0 65-70 30-35 65-70 30-35 65-70 30-35 30 70

M17 44.18 21.03 (7-10 mm) 61.04 40 (4-8 mm) 60 (1-4 mm) 15.9 2.04

Med 100 0 50 50 50 50 50 50 50 50

M18 44.41 45.02 (5 mm) 49.22 5-10 (4-8 mm) 90-95 (1-4 mm) 5.04 0.71

Med 0 100 3-5 95-97 3-5 95-97 3-5 95-97

48

Table 3.6. The results of the acid loss+ sieve analysis and the ignition loss analysis of the mortar

samples

Sample

No

Humid

%

550o C

%

CaCO3

%

Acid

Lost

%

Acid

Retained

%

Coarse + (*)

Aggregates

A, %

Coarse + (**)

Aggregates

B,%

(***)

1000

%

(***)

500

%

(***)

250

%

(***)

125

%

(***)

<125

%

M1 1.81 4.17 45.59 51.35 48.65 15.08 26.74 57.34 4.84 28.63 3.61 5.58

M2 4.27 4.97 27.96 63.35 36.65 25.73 48.59 66.39 3.44 20.98 2.46 6.72

M3 16.02 15.21 26.96 56.22 43.78 10.02 20.27 75.28 3.58 13.43 2.00 5.72

M4 0.71 5,53 25.19 46.83 53.17 8.78 15.33 74.09 5.56 14.04 1.75 4.56

M5 6.11 13.42 18.53 54.57 45.43 8.58 17.12 69.29 3.84 16.70 3.13 7.05

M6 1.33 6.58 35.54 55.95 44.05 6.83 14.27 71.65 2.34 14.21 2.56 9.23

M7 4.58 9.12 40.43 60.53 39.47 0.00 0.00 57.33 2.76 28.00 4.18 7.73

M8 1.05 4.23 55.76 47.25 52.75 0.00 0.00 65.50 3.61 22.42 2.44 6.04

M9 2.28 5.89 51.86 61.29 38.71 0.00 0.00 51.82 3.64 32.70 6.05 5.80

M10 4.41 6.94 28.28 39.95 60.05 13.95 21.26 48.37 3.42 42.31 2.31 3.58

M11 5.13 6.20 26.14 53.55 46.45 18.45 32.75 58.05 6.23 27.44 2.36 5.93

M12 6.93 7.93 24.35 38.43 61.57 8.75 13.47 51.32 2.93 36.40 3.90 5.45

M13 5.30 8.07 34.50 59.82 40.18 4.90 11.37 46.38 5.11 35.95 5.06 7.49

M14 0.41 4.21 80.36 89.50 10.50 0.99 8.70 6.94 4.01 61.73 14.66 12.65

M15 2.15 9.61 26.25 64.29 35.71 28.74 53.05 60.89 6.15 23.00 2.70 7.26

M16 1.68 3.37 41.01 55.41 44.59 27.52 45.99 57.77 7.67 24.66 3.59 6.31

M17 8.04 8.72 37.53 63.44 36.56 12.01 27.19 69.06 5.34 17.51 4.57 3.52

M18 1.80 3.04 80.83 87.45 12.55 36.42 82.03 42.12 3.15 40.40 7.16 7.16

(*) :Proportion of the coarse aggregates vs the amount of the mortar sample

(**) :Proportion of the coarse aggregates vs total aggregates.

(***) :Sieve distribution of those aggregates do not include the coarse ones.

49

3.1.2.1. The Results of the Analysis of Natural Stones, Bricks and Mortars

Natural Stones;

Petrographic analysis of the natural stones indicated that the samples S1, S3, S4, S9 and S10

were microcrystalline limestones with calcite, samples S5, S7 and S8 were fossiliferous

microcrystalline limestones and sample S2 was an oolitic limestone. All of them were organic

limestones (with calcites, oolithes and fossils ), and they were locally named as “Küfeki Stone”,

all of them were extracted from the Merter and Bakırköy region close to the land walls of

Constantinople. The sample S6 is a marble which probably was quarried from the Marmara

Island (Proconnesses).

The DTA curves (Figure 3.36) of limestones indicated that the main components of the samples

are CaCO3.

The semi-quantitative analysis of the water soluble salts indicated that the stone samples S1, S2,

S9 and S10 included considerable amounts of Cl- salts, while samples S2, S7, S8, S9 had SO4

-2

salts.

The results of the ICP analysis gave the general compositions of the limestone samples, the Cl-

and SO-2

4 (as S) contents seem to support the data derived from the semi-quantitative analysis.

The samples S7, S8, S9 which was taken from the altered evaporation front of a limestone from

T4 of landwalls of Constantinople contained 2-9 times more SO4-2

salt when compared to the

samples which were taken from the sound core of those limestone blocks. The SO4-2

salt was

accumulated as a black gypsum crust on the surfaces of the limestone samples which were

exposed to the polluted air. Dust, soot and clay were trapped during the surface condensations.

Consecutively the SiO2 contents of a contamined samples, S7, S8, S9 were increased on their

surfaces. The sample S10 showed a contrary result where it was sampled from the sound core

of the same limestone block. Also no SO-2

4 salt was detected in the clean and sound core. The

Cl- salt content was doubled because the stone sample was in contact with the joint mortar, as

stone laying and pointing mortars included more Cl- salt. The production, migration and

crystallisation of the Cl- and SO

-24 salts during the wetting and drying cycles had caused

efflorescence and surface erosion in the forms of fissures, flaking and crumbling. The results of

the ICP analysis also indicated that the stones S2, S4, S5 and S10 included Cr salt ranging

between 0.003-0.006 %. Contamination due to the Cr salt was originating from the leather

manufacture (tanning) processes which took place in the factories which were adjacent to the T4

and the adjoining rampart for the last four decades before the urban clearance.

In regard to the results of the ICP analysis, the Cr salts contamination was limited and since Cr

salts are not water soluble they do not cause physico-chemical deterioration processes, whereas

they create aesthetic problems.

Bricks;

The DTA curve and the XRD patterns (Figure 3.34) brick of (Figure 3.36) indicated that the

main component of the sample is SiO2.

50

Petrographic analysis of the 5thC. and the medieval bricks indicated that the minerological

compositions of all of them were similar to each other. But the amounts of the minerals and their

porosities changed from one sample to another. Sample B1 (yellow coloured medieval brick) had

smaller particles than the others. The other minerals of the brick samples were similar to each

other.

The alteration of the limestone particles in the exhibited similar deterioration processes as the

limestones. These results which were derived from the petrographic analysis were correlated to

the results of the ICP analysis. All of the samples included SO4-2

salt in amounts between 0.02-

0.08%. Sample B3 and B4 (medieval) included small amounts of Cl- salt, while B1 included

almost no Cl- salt. The brick samples B2 and B5 and the surface stratum of the sample B3 (all

medieval brick) had larger amounts of Cl- salt, B6 which is a 5

thC brick had excessive amount of

Cl- salt, which can originate from the production technology or the accumulation of the Cl

- ions

by means of sea spray coming from Marmara sea, percolating rain water, since the sample was

taken from the ground level of T4, from the passageway from the city to the ground floor,

(Figure 2.1) where the stones, bricks and the mortars were exposed to weathering processes for

centuries.

Bricks for the conservation works :

The 5th

C. and the medieval bricks were 38/38/4-5 cm sized, where the Late Byzantine bricks

were sized 35/35/3.5 cm, and 32-34/32-34/2.5-3.5 cm bricks were also found in the landwalls of

the city. The physical and the mechanical properties of Byzantine bricks were heterogenous due

to the production techniques and their state of conservation. The average values for Byzantine

bricks of the 5th

-14th

centuries can be summarized as follows:

Density : 1.55-1.89 g/cm3

Water Absorption (by weight,%) : 14.7-22.05

Table 3.7. The physical and the mechanical properties of the bricks which were produced in the

Brick Kiln Kılıçoğlu in Eskişehir

Dimensions Density

(g/cm3)

Water Absorption

(by weight, %)

Coefficient of

Capillary (cm.min)

Compressive

Strength (N/mm2)

38/36/5.5 1.97 10.7 0.112 27.6

30/15/3 1.95 11.5 0.116 25.7

32/17/3.5 1.96 10.7 0.073 28.5

*The results were the average of 5 samples, the tests were conducted in 1993 during the conservation

works in the land walls of Constantinople at Yedikule, Sulukule Kapı (Porta Pempton) and Topkapı (Porta Romanus).

Mortars

The DTA curves (Figures 3.25, 3.3) and the XRD patterns (Figure 3.2) of the mortars indicated

that the main component of the samples are both SiO2 and CaCO3. The results of the

petrographic analysis (Table 3.4), the ignition loss (Table 3.6) and the acid loss and the sieve

analysis (Table 3.5 and 3.6) of the siliceous aggregates and the crushed brick particles had given

the binder / aggregate ratios of the original samples. Also additives and their some physical and

chemical properties were determined (Table 3.9 and 3.10). The acid insoluble aggregates

presented an important data in regard to their grading, especially gravel sized brick particles

51

which were mostly 8-20 mm sized were calculated as their ratio to the sum of the aggregates

(first method) and to the weight of the mortar sample (second method) as a whole for

characterisation purposes. In the second method the ratio of the gravel sized coarse brick

aggregates to the sample weight was between 1-36 %. In the first method, it was observed that

the ratio of the coarse brick particles to the total amount of the aggregates (by weight) led to

incorrect conclusions. Because these brick particles which were 8-16 mm mesh size and above,

were scattered in large amounts of mortar and when sampled in 40-50 g lumps, the binder :

aggregate ratios were deviating from the real values. The ratio of the coarse aggregates in the

total of the aggregates were as much as 82 %. Because of these diversity in the total aggregate

ratio, the ratio of the gravel sized brick particles, were evaluated separately the binder : aggregate

ratios do not include the 8-16 mm and >16 mm mesh size brick particles. Instead they were

included to the total sum of the aggregates in the calculations in regard to total aggregate : binder

ratios of the mixes. As a result this method the binder : aggregate ratios were generally 1:3

(samples M1, M7, M8, M10, M14, M16, M17 and M18), and 1:4 (M2, M3, M4, M6, M11, M12

and M15). Sample M5 had a 1:6 ratio, where samples M9 and M13 had 2:7. Samples could not

be categorized according to binder : aggregate ratios in the historic timeline, since ratios were

randomly detected in all ages. Petrographic analysis of the mortar samples showed that all of

them had crushed limestone (limestone chips and pieces) aggregates with or without fossils as

afore mentioned. Limestone pieces were mostly crushed local limestone which was used in the

construction, and should be the chips which were left by the stone masons during their stone

dressing for the ashlar blocks which were used for the facework. (Figure 3.64, 3.65, 3.66, 3.67,

3.68, 3.69). Lesser amount was provided from natural sources which were rounded. The amount

of the limestone aggregates differed from sample to sample. The other aggregates were mainly

quartz, quartzite (Figure 3.72, 3.73) feldspar, granite (Figure 3.77). Other igneous rock particles

which can be accepted as impurities were plagioclase, pyroxene, biotite and opaque iron oxide

minerals (Figure 3.74). The crushed brick and the brick powder was used both as a artificial

pozzuolanic additive and as aggregates, where fines of the brick powder reacted with Ca(OH)2.

Brick powder was not used in the sample M14 which belonged to the 15thC repairs. A few brick

particles was of medium size were detected in the mortar in situ, but it did not effect the colour

of the mortar. The amounts of the brick particles differed in between 5-70 % in different samples

regardless to the chronology (Table 3.5).

Many of the feldspar particles were partially altered in different morphologies such as cracking,

crumbling, and, clay (Figure 3.78, 3.79) and carbonate formation (Figure 3.68). In sample M16

(Figure 3.81, 3.82) orthose was observed. Some quartzite exhibited micro cracks and some of the

plagioclase particles were partially altered. The adherence at the aggregate / binder interstices of

those altered aggregates were weaker than the adhesion at the brick particle/binder interstices.

The gel formation was observed on the surfaces and on the surrounding areas of the crushed

brick particles (Figure 3.81, 3.82). These pozzolanic properties led to a good adhesion between

the binder and the crushed brick particles.

The amount of the CaCO3 in the mortars samples which were determined by means of the

ignition loss test were correlated with the results of the ICP analysis. The ICP analysis results of

the mortar samples (Table 3.1) also were correlated with the amount of the crushed brick in

them. As the amount of the crushed brick increased in the samples, the amounts of the Al2O3,

Fe2O3, Ba and Zr contents were increased in direct proportion. When the amounts of the Al2O3

and Fe2O3 in the mortar samples compared with the amount of the crushed brick, it can be

concluded that the results of the acid loss and sieve analysis, ignition loss and petrographic

analysis were correlated with the results of the ICP analysis.

52

The poor adhesion of the sample M5 depends on the inappropriate composition. Since the

khorasan mortars which was used in the construction of the land walls was produced in large

quantities, it was quiete normal to result with heterogenously mixed batches. Also mortars were

exposed to precesses of weathering and mechanical deterioration under different loads. Also,

their location in the structure determined their state of conservation. The locations of the samples

M1 and M7 (Figure 3.64, 3.72) were shown in Figure 2.1. Since those samples subjected to

wetting and drying cycles, and, the water soluble salts were not washed away with rainwater,

thus, these samples were deteriorated by crystallisation pressures (efflorecence and

cryptoflorecence) of the water soluble salts. Cl- ions were accumulated in all of the samples

which were sampled from the different parts of the Tower T4 which had originated from the sea

spray. The water soluble salts which were easily soluble were washed away with rain water as in

the mortar samples M4, M6, M14, M16 and M18. The mortars which were sampled from the

interior or relatively sheltered parts included large amounts of water soluble salts originating

from sea spray and polluted air. These were absorbed by the mortar surfaces during and after

surface condensations and had been accumulated in the pores. But when the wetting-drying

cycles were minimum or neglectable in the sheltered parts samples were sound and were not

decomposed by salt crystallisation pressures. Although mortar samples M16 and M17 were

sampled from the same location, the sample M17 which remained dry had 9549 p.p.m Cl- ions,

while the one which was washed with rainwater had 562 p.p.m Cl-

ions. But in both cases the

deterioration due to salt crystallisation was not drastic. And there had been a gradual and

progressive surface erosion process on the ruined parts where the corework was exposed to

weathering, whereas the sheltered parts or the interior of the tower was relatively well protected.

53

3.1.3. The Physical Properties of the Natural Stones, Bricks and the Mortars

The physical properties tests conducted on the stone, brick and mortar samples of the T4

landwalls of Istanbul. The tests were conducted according to TSE 699 (ASTM C97-96, ASTM

C20-92, ASTM C 121-90, ASTM E 12-70).

Table 3.8. The results of physical property tests of stone and brick samples

- (*) Unable to determine the property of water vapour diffusion resistance factor.

S : Stone sample B : Brick sample

CC : Coefficient of capillary WA : Water absorption

D : Density SG : Specific gravity

C : Composity P : Porosity

SD : Saturation degree μ : Water vapour transmission

No of

Samples

CC

(gr/cm2sn)

W A

(by weight)

(m/m, %)

WA

(by volume)

(v/v, %)

WA

(in boil. wat.)

(m/m, %)

WA

(in boil. wat.)

(v/v, %)

D

(gr/cm3)

SG

(gr/cm3)

C

(%)

P

(%)

S D

(%) μ

S1 3.2*10-5 4.25 8.54 9.41 18.76 2.01 2.68 75.18 24.81 34.42 - (*)

S2 6.6*10-5 6.49 11.42 15.47 27.29 1.76 2.72 64.88 35.11 32.53 - (*)

S3 2.8*10-5 3.64 7.93 5.00 10.39 2.18 2.74 79.74 20.26 39.14 77,19

S4 4* 10-5 7.03 12.87 14.82 27.01 1.83 2.76 66.30 33.70 38.21 81,42

S5 2.8*10-5 2.36 5.69 3.77 8.99 2.41 2.77 87.00 13.00 43.76 - (*)

S6 0.97*10-6 0.18 0.50 0.28 0.76 2.71 2.79 97.13 2.87 17.33 - (*)

S7 Medieval

2.4*10-4 3.52 7.46 6.23 13.18 2.12 2.67 79.40 20.60 36.22 - (*)

S8

Medieval 6.6*10-4 1.55 3.98 1.90 4.91 2.57 2.67 96.02 3.98 100.00 - (*)

S9 5th C.

3.6*10-4 2.57 5.98 4.71 10.93 2.33 2.68 86.94 13.06 45.79 96,41

S10 Medieval

6.3*10-4 6.04 11.57 12.04 22.99 1.91 2.64 72.35 27.65 41.84 - (*)

B1 Medieval

3.4*10-4 19.84 33.68 20.74 35.16 1.69 2.62 64.50 35.50 94.88 - (*)

B2 Medieval

1.7*10-4 15,33 27.96 15.68 28.48 1.82 2.66 68.42 31.58 88.54 - (*)

B3

Medieval 2.9*10-4 16,77 29.89 18.30 32.25 1.77 2.74 64.60 35.40 84.43 33,29

B4 Medieval

2.5*10-4 15,32 27.94 16.23 29.45 1.82 2.74 66.42 33.58 83.21 36,21

B5 Medieval

1.87*10-4 15,97 27.78 16.49 27.65 1.74 2.68 65.32 34.68 90.10 - (*)

B6 5th C.

3.09*10-4 22,44 35.68 23.29 36.93 1.59 2.74 56.93 43.07 82.84 - (*)

54

Table 3.9. The results of physical property tests of the mortar samples

- (*) Unable to determine the physical properties.

No of

Samples Century

W A

(by weight)

(m/m, %)

WA

(by volume)

(v/v, %)

D

(gr/cm3)

SG

(gr/cm3)

C

(%)

P

(%)

S D

(%)

M1 5th Century 21.08 34.02 1.62 2.63 61.60 38.40 88.60

M2 5th Century 13.43 26.86 2.00 2.56 78.14 21.86 100.00

M3 Medieval 35.54 53.16 1.50 2.59 57.91 42.08 100.00

M4 Medieval 20.74 34.80 1.68 2.56 65.62 34.37 100.00

M5 Medieval - - - - - - -

M6 Medieval 31.51 44.44 1.41 2.53 55.75 44.25 100.00

M7 5th Century 21.49 35.50 1.65 2.59 63.70 36.29 97.83

M8 5th Century - - - - - - -

M9 Medieval - - - - - - -

M10 5th Century 15.26 26.50 1.73 2.59 67.05 32.95 80.42

M11 5th Century 19.30 32.42 1.68 2.53 66.40 33.60 96.49

M12 5th Century 18.30 30.56 1.67 2.58 64.73 35.27 86.64

M13 5th Century 18.40 30.54 1.66 2.64 62.88 37.12 82.27

M14 15th Century 18.72 31.10 1.69 2.56 66.02 33.98 86.45

M15 Medieval 28.17 41.65 1.48 2.40 61.66 38.34 100.00

M16 Medieval 28.30 41.60 1.47 2.39 61.50 38.50 100.00

M17 Medieval 28.30 41.60 1.47 2.39 61.50 38.50 100.00

M18 Medieval 28.20 42.30 1.50 2.47 60.73 39.43 100.00

55

3.1.4. The Mechanical Properties of the Natural Stones, Bricks and the Mortars

The mechanical tests were conducted according to TSE 699 (ASTM C120-90, ASTM C170-90).

The determination of compressive strength tests were conducted by using (Form-Test-Seidner-

Co GMBH, D-7940 Riedlingen West Germany) universal press with 3000KN capacity. And, the

determination of tensile strength tests were conducted by using Mfl Systeme (GMBH, D-6800

Mannheim) universal press with 100KN capacity.

Table 3.10. The results of mechanical property tests of the stone and the brick samples

- (*) Unable to determine the mechanical properties.

Point load test : Since the original mortar samples were too weak, the mechanical properties

could not be found by uniaxial compressive strength test. So, the compressive strengths of

the original mortar samples were determined by conducting the point load method and the

results were converted to uniaxial compressive strengths.

No of

Samples Century

Compressive

Strength

(c, N/mm2)

Tensile

Strength

(t, N/mm2)

S1 5thC + Med 20.3 3.1

S2 5th

C + Med 11.7 1.8

S3 5thC + Med 37.3 7.5

S4 5thC + Med 18.9 4.0

S5 5thC + Med 32.5 0.8

S6 5thC + Med 77.3 8.8

S7 Medieval 21.6 7.0

S8 Medieval 46.0 -

S9 5th Century 25.3 7.06

S10 Medieval 20.7 4.10

B1 Medieval 25.0 -

B2 Medieval 14.3 -

B3 Medieval 16.4 4.8



B6 5th Century 14.9 4.3

56

This test method was recommended by ISRM (International Society For Rock Mechanics.

Comission on Standardization of Laboratory and Field Tests).

The tests were conducted both on the original mortar samples and the repair mortar samples

by point load test. The compressive strengths of the repair mortars also determined to

compare the results and to find a correction factor, since they were tested by uniaxial

compressive strength test before and average values were evaluated.

(a) (b) (c)

Figure 3.84. (a,b,c) The point load testing method.

The compressive strength formula recommended by ISRM was :

σ = (0,89 x Fp) : d2

d = Thickness of the sample (mm)

Fp= Applied load (N) / Correction factor = 10 was found.

Table 3.11. The comparative results of the mortar samples after the point loading test

Mortar

Samples

Compressive

Strength (MPa)

Uniaxial Compressive

Strength (MPa)

(with correction)

Original 5th Century 0,4

* 4

*

Mortars Medieval 0,5*

5*

15thCentury 0,6

* 6

*

Repair 5th Century 0,6

* 6

*

Mortars Medieval 0,6*

6*

15thCentury 0,7

* 7

*

(*)The values were approximate.

57

3.2. The Choice of the Natural Stones for Replacement and Indenting

Two different limestones were chosen for the repair of the original and the subsequent parts, one

being an organic limestone (fosiliferous) quarried at Pınarhisar, Kırklareli and a chemically

precipitated (sedimentary) limestone, with small amount of quartz and microfossils, the Kandıra

stone which is quarried at Kandıra Kocaeli.

The Pınarhisar limestone quarries are located around the Erenler village of the Kandıra province

and they are consisted of oligocene aged fossiliferous limestones and marls. These quarries were

used throughout the Byzantine and the Ottoman eras. The beds of the sedimentation is

approximately 70 cm thick and are composed of sparitic limestones and marls. Blocks of 0.5-1

m3 fossiliferous limestone can be extracted, marly parts are alternatively bedded, consequently

stone to be used for conservation works should be selected in the quarry.

Figure 3.85. The map of Marmara Region

Kandıra limestone has a wide area of quarrying, this different samples extracted from different

quarries exhibit heterogenous physical and mechanical properties. The most durable samples are

quarried at Akçaova, Örentepe region at west Kandıra. There are several actively managed

quarries at Örentepe. The paleocene unit has random beds of pale yellow and brown siliceous

limestones and pale grey marls. The beds have an average thickness of 0.4-0.6m, exceptionally

5-6 m3 blocks could be extracted due to the increasing thicknesses of the beds. The physical and

mechanical properties of the Kandıra stone was given in Tables 3.12 and 3.13.

58

Table 3.12. The physical and mechanical properties of Pınarhisar, Erenler Organic (fosiliferous)

limestone

Physical and

Mechanical Properties

Maximum Minimum Mean

Density (g/cm3) 2.29 2.25 2.27

Saturated Density (g/cm3) 2.33 2.27 2.30

Specific Gravity (g/cm3) 2.65 2.65 2.65

Porosity (%) 15 14 14.40

Water Abs. (By Weight) % 4.57 3.96 4.33

Water Abs. İn Boiling Water

(By Weight) % 5.28 4.98 5.03

Coefficient of Capillarity

(kg/cm2√min.)

0.0508 0.0308 0.0384

Coefficient of Water Vapour

Transmission Resistance 16 8 12

Compressive Strength (MPa) 45.67 19.9 30.4

Tensile Strength (MPa) 1.10 1.01 1.07

Elasticity Modulus (GPa) 17.25 8.90 13.4

Table 3.13. The physical and mechanical properties of Kandıra Limestone

Physical and

Mechanical Properties

Maximum Minimum Mean

Density (g/cm3) 2.56 2.38 2.51

Saturated Density (g/cm3) 2.58 2.48 2.57

Specific Gravity (g/cm3) 2.58 2.58 2.58

Porosity (%) 10.11 4.96 6.17

Water Abs. (By Weight) % 4.25 1.94 2.49

Water Abs. İn Boiling Water

(By Weight) % - - -

Coefficient of Capillarity

(kg/cm2√min.)

- - 0.01437

Coefficient of Water Vapour

Transmission Resistance - - 70

Compressive Strength (MPa) 103.29 58.51 79.20

Tensile Strength (MPa) 3.83 2.35 2.95

Elasticity Modulus (GPa) 13.59 10.08 12.25

The Petrographic Analysis of the Stones :

Pınarhisar Organic (fosiliferous) Limestone; The rock is creamy white, the grains are

medium sized, peloids, mollusus and bentonitic foraminifers, oolites and ecinoderm particles

59

were detected. The peloids were almost spherical and partially replaced by microcrystalline

calcite. These particles were most probably bioclasts or oolites in the original phase. The

grains were cemented with fine crystalline sparicalcite cement. This natural cement was

formed during the sedimentation early and late consolidation phases in the intergranular

pores. The other diagenetic alteration was the formation of the siliceous minerals. The

porosity was small and the pores were mostly secondary and formed by dissolution.

Considerable amounts of compactions and consecutive micro cracks were observed. The

micro cracks were filled with sparicalcite. Also recrystallisation was widely detected.

Kandıra (sedimentary) Limestone : Kandıra limestone has a creamy-yellowish hard rock.

The grains were mostly rounded and the dimensions of the grains were homogenous, and the

polished thin section did not exhibit a porous structure. Partially minor amounts of mafic

minerals were detected, no alteration was observed. The sample had a crystalline structure,

plagioclases and remains of fossils were also detected. Secondary formations and

recrystallisation was the general character of the texture. Partially oolitic structures and

siliceous formations were seen between the calcite crystals.

X-Ray Diffraction analysis of the Pınarhisar and the Kandıra Limestones :

Pınarhisar (Erenler), organic limestone had high amount of calcite and a minor amount of

quartz.Kandıra (Akçaova), limestone had high amount of calcite and less than quartz.

ICP analysis of the Pınarhisar Organic Limestone and the Kandıra Limestone :

Table 3.14. The results of the ICP analysis for the Pınarhisar and the Kandıra Stones

Composition of

the Stones

Pınarhisar

Organic Limestone Kandıra Limestone

SiO2 % 2.06 2.95

AL2O3 % 0.36 0.72

Fe2O3 % 0.33 0.72

MgO % 0.18 0.40

CaO % 54.93 53.09

Na2O % 0.03 0.06

K2O % 0.11 0.13

TiO2 % 0.01 0.02

P2O5 % 0.08 <0.01

MnO % 0.02 0.05

Cr2O3 % <0.001 <0.001

Ba ppm 25 15

Ni ppm 34 37

Sr ppm 145 590

Zr ppm <10 <10

Y ppm <10 <10

Nb ppm <10 <10

Sc ppm <1 1

Loss of Ignition 41.9 41.8

Total C 11.66 11.56

Total S 0.01 0.01

60

3.3. Designing and Production of the Repair Mortars

Three different compositions were designed for the repair and reintegrations of the 5th

C., the

medieval and the 15th

C. mortars. The colours and the textures of the 5th

C. and the medieval

khorasan mortars were similar on visual inspections, but however the grading of the coarse brick

aggregates and the binder: aggregate ratios were different. Whereas 15th

C. samples were

completely different from the standpoint of their compositions and colours and the textures. The

5thC. and the medieval mortar samples were pinkish-creamy white with visible coarse brick

aggregates whereas the 15th

C. mortar samples were light grey-creamy white with only visible

medium sized sad. The latter was used with brick pieces inserted in the mortar in the large joints

of the stones in its authentic construction technique.

Fifteen trial mixes for the 5th

C. samples, 9 trial mixes for the medieval samples and 6 trial mixes

for the 15thC. samples were designed, produced and casted in 4/4/16 steel moulds. After fixing

the binder : aggregate ratios, the amount of the fine aggregates were adjusted for determining the

colour of the lime paste. The binder was always slaked lime and ground volcanic tuff mixed in

3:1 ratio. The aggregates were crushed brick and powder and river sand mixed in the ratios of the

original sample. The original ratios of the crushed brick and the river sand were determined by

means of evaluation of the data derived from the acid loss and sieve analysis, and petrographic

analysis of the original samples. The amounts were slightly corrected according to the standard

grading (ASTM C 144-99 and TSE 706). Before the commencement of the preparation of the

samples, the aggregates were sieved and grouped according to mesh sizes and their bulk

densities and specific gravities were calculated. In total 72 samples were prepared for each

period making sum of 216 samples which will be conducted to the tests to determine their

physical and mechanical properties after curing periods of one month, three months and six

months. The samples were programmed to be cured in tightly sealed polyethylene bags at 23 ±2o

C and in 90-100 % RH for 6 months. The only additive which was used was a water reducer

(Melment F10, YKS, 0,1 % in water).

The mortar mixes were mixed by hand untill a homogenous mixture was obtained and vibrated

for 15 seconds. The initial setting time was 48 hours for all of the sample groups.

Figure 3.86. The samples of the repair mortars

61

3.3.1. Properties of the Raw Materials Used in the Trial Mixes

Lime : The water content of the slaked lime was 45 % and this was converted CaO to match the

original binder amount. The lime consisted of 37.90 % Ca(OH)2.

Pozzolana: The pozzolana (ground tuff) which was taken from Konya, was used for the trial

mixes. The ratio of the pozzolana : slaked lime was accepted as 1:3 in regard to the mechanical

properties of the oiginal samples. The chemical composition of the pozzolana was given in the

Table 3.14.

Table 3.15. The results of the chemical analysis of the pozzolana (ground volcanic tuff of

Konya, Central Anatolia, Turkey) (*)

(*) N. Koçu, “Konya Çevresindeki Volkanik Tüflerin Yapı Malzemesi Olarak Değerlendirilmesi

ve Özelliklerinin Belirlenmesi Üzerine Bir Araştırma”, Ph.D. Thesis, Institute of Natural

Sciences of I.T.U., İstanbul, 1997 , page no. 63

Table 3.16. The results of the XRD Analysis of the volcanic tuff of Konya (I.T.U. Material

Science Laboratory of the Faculty of Chemistry and Metallurgy, Dmax-1000 X-Ray

Diffractometer) (*)

Mineral Type Chemical Formula

ASTM Card No

Jarosite KFe3(SO4)2(OH)6 22-827

Quartz SiO2 33-1161

Silicon Oxide SiO2 29-85



Sciences of I.T.U., İstanbul, 1997 , page no. 64

Name of

the Lab. SiO2 Fe2O3 Al2O3 CaO MgO Na2O TiO2 K2O SO4 AZ SUM L01 HM SM AN

Technical University of İstanbul, Faculty of Mining

65.01 9.41 3.77 0.23 0.08 0.57 - 2.07 5.30 - 86.45 11.92 0.0 4.93 0.40

Seydişehir Aluminium

Factory Chemistry Lab.

68.10 10.86 2.39 0.56 - 0.17 0.80 2.13 8.04 11.28 - - - - -

62

Table 3.17. Evaluation of the results of the XRD Analysis and Minerological Analysis

(I.T.U., Faculty of Mines, Department of Mineralogy) (*)

Mineral Type Chemical Formula Amount of it in the raw

material (%)

Jarosite KFe3(SO4)2(OH)6 60-70

Opal Crystobalite SiO2 15-20

Quartz SiO2 8-10

Amorphous Opal SiO2..nH2O 10-20

Table 3.18. Sieve analysis of the ground volcanic tuff which was used as the pozzolanic additive

Mesh Size (µ) Retained (g)

Passed (g)

211 0,0 100

40 38 62



Sciences of I.T.U., İstanbul, 1997 , 78

Figure 3.87. SEM micrograph of the Konya volcanic tuff dust, quartz crystal on the right.

(Tuff dust is composed of fines around 3-5 microns size)

Figure 3.88. EDX diagram of the Konya Volcanic tuff

63

Pozzolanic Activity Test

The pozzolanic activity tests contributed to the determination of the pozzolanic properties of the

volcanic tuff which was used. They were conducted in compliance with TS 25. In the test

procedure ; the hydrated lime (666.6g), pozzolana (613.6g), standard sand (2700g) and water

(90g) were mixed. The mixtures were casted in steel moulds. Moulds were rested in a

polyethylene bag for one day at the room temperature. Then, the moulds were placed and kept in

the oven at 55oC for 6 days for the curing programme. After six days, the samples were taken off

from the moulds and left at the room temperature for cooling. Consecutively for 1 week, 2 weeks

and 1 month old samples, the compressive and the tensile strength tests were conducted.

Table 3.19. Compressive strengths of the samples after 1, 2 weeks and a month

The Samples

Curing

Time

Dimensions

(cm)

Compression

Stress (N)

Compressive

Strength (MPa)

Sample 1 1 week 7/7/7 97.400 19.63

Sample 2 2 weeks 7/7/7 104.000 20.96

Sample 3 1 month 7/7/7 99.000 20.06

Table 3.20. Tensile strengths of the samples after 1, 2 weeks and a month

The Samples

Curing

Time

Dimensions

(cm)

Tensile

Stress (N)

Tensile

Strength (MPa)

Sample 1 1 week 4/4/16 1380 4.85

Sample 2 2 weeks 4/4/16 1650 5.86

Sample 3 1 month 4/4/16 1730 6.05

According to TS 25, The compressive strength must be at least 4 MPa for the samples after 7

days of curing time and the tensile strengths must be at least 1 MPa. As the results were above

the minimum values. These results indicated that the volcanic tuff which was used as a

pozzolanic additive, was very active for silicate forming reactions. The results were given in

Tables 3.19 and 3.20.

Table 3.21. Bulk densities and the specific gravities of the aggregates which were used

for the mixtures of the repair mortars

Materials

Bulk Density

(g./cm3)

Specific

Gravity

(g./cm3)

Lime 1.41 2.28

Pozzolana 0.71 2.33

Aggregates Crushed Brick River Sand

B.Density S. Gravity B.Density S. Gravity

8 mm 0.85 1.45

4 mm 0.86 1.43

2 mm 0.87 1.37

1 mm 0.9 2.57 1.53 2.59

0.5 mm 1.05 1.38

0.25 mm 1.04 1.36

<0.25 mm 0.94 1.38

64

3.3.2. Mix Designs of the Repair Mortars

Mix design for the repair mortar to match the properties of the 5th

C khorasan mortar :

Sample Code = 5C1-5C2-5C3 (For 1 month-3 months-6 months old)

Binder : Aggregate Ratio = 1:2 as in the original mortar samples

Slaked Lime: Pozzolana Ratio = 3:1

Crushed Brick = 40 % of the total aggregates

River Sand = 60 % of the total aggregates

Grading of the aggregates which were used

Mesh size %

16-8 mm 24

8-4 mm 26

4-2 mm 17

2-1 mm 13

1-0,5 mm 9

0.5-0.25 mm 6

<0.25 mm 5

03

7

12

21

36

60

100

0

5

11

20

33

50

76

100

0

8

20

32

42

56

76

100

0

18

34

49

62

74

88

100

0

10

20

30

40

50

60

70

80

90

100

0 0.25 0.5 1 2 4 8 16

mesh size (mm)

Perc

en

tag

e o

f p

assed

(%

)

A

5C

B

C

Figure 3.89. The grading of the aggregates of the 5

th C. mortar sample

A,B,C :The ideal amounts of the passed aggregates were shown in TSE 706- Fuller Parabola,

5C : The passed aggregates of the trial mix for the repair mortar to match the 5th C sample.

65

Mix design for the repair mortar to match the properties of the medieval khorasan

mortar :

Sample Code = M1-M2-M3 ( For 1 month-3 months-6 months old)

Binder : Aggregate Ratio = 1:2 as it was in the original samples.


Crushed Brick = 67 % of the total aggregates

River Sand = 33 % of the total aggregates


Mesh size %

16-8 mm 16

8-4 mm 29

4-2 mm 22

2-1 mm 15

1-0,5 mm 9

0.5-0.25 mm 6

<0.25 mm 3

03

7

12

21

36

60

100

03

9

18

33

55

84

100

0

8

20

32

42

56

76

100

0

18

34

49

62

74

88

100

0

10

20

30

40

50

60

70

80

90

100

0 0.25 0.5 1 2 4 8 16

mesh size (mm)

Perc

en

tag

e o

f p

assed

(%

)

A

M

B

C

Figure 3.90. The grading of the aggregates for the repair mortar to match the medieval samples

A,B,C :The ideal amounts of the passed aggregates were given in TSE 706- Fuller Parabola.

M : The amount of the passed aggregates of the trial mix for the repair mortar to match the medieval

mortar.

66

Mix design for the repair mortar to match the 15th

C khorasan mortar :

Sample Code = 15C1-15C2-15C3 (For 1 month-3 months-6 months old)

Binder : Aggregate Ratio = 1:3 as it was in the original samples.


Crushed Brick = 2.35 % of the total aggregates

River Sand = 97.65 % of the total aggregates


Mesh size %

16-8 mm 0

8-4 mm 0

4-2 mm 26

2-1 mm 21

1-0,5 mm 21

0.5-0.25 mm 25

<0.25 mm 7

0

8

20

34

60

100

0

7

32

53

74

100

0

15

35

57

77

100

0

25

45

67

85

100

0

10

20

30

40

50

60

70

80

90

100

0 0.25 0.5 1 2 4

mesh size (mm)

Perc

en

tag

e o

f p

assed

(%

)

A

15C

B

C

Figure 3.91. The grading of the aggregates for the repair mortar to match the 15

th C. mortar

A,B,C :The ideal amounts of the passed aggregates were given in TSE 706- Fuller Parabola.

15C : The amount of the passed aggregates of the trial mix for the repair mortar to match the 15thC

mortar.

67

3.3.3. Experimental Works for the Repair Mortars

Sevaral experimental works were conducted to determine the characteristics of repair mortars.

Before conducting the tests, code systems were contriboted to the samples.

Table 3.22. Sample code system for the repair mortars prepared in the Laboratory of Building

Material Testing Laboratory of the Faculty of Architecture, I.T.U

Sample Codes 1 Month Old 3 Months Old 6 Months Old

5th Century 5C1 5C2 5C3

Medieval Age M1 M2 M3

15th Century 15C1 15C2 15C3

The tests for the determination of the physical and mechanical properties were conducted on the

samples as the ageing tests after 30, 90 and 180 days. Porosimetries (pore size distribution of the

repair mortars were determined after 180 days). All of the samples were casted in 4/4/16 cm.

dimensioned steel moulds, except the samples which were prepared and cured for the

compressive strength tests which were 7/7/7 cm. dimensioned cubes. The tests which were

conducted in the testing programme for the evaluation of the physical and mechanical properties

of the repair mortars and their sample sizes were given in Table 3.23.

Table 3.23. The experimental programme conducted on the repair mortars for the determination

of their physical and mechanical properties and evaluation of their durabilities

1.) Qualitative And Quantitative Analysis Of The Water-Soluble Salts

2.) The Petrographic Analysis

Petrographic analysis on polished thin sections

SEM-EDX Analysis

3.) Determination Of The Physical Properties

Coefficient of Capillarity (g/mm2√s) (4x4x16 cm.) x 6

Water Absorption (by weight) (%) (4x4x16 cm.) x 6 TSE 699

Water Absorption (by volume) (%) (4x4x16 cm.) x 6 ASTM C20-92

Water Absorption in Boil. Water (by weight) (%) (4x4x16 cm.) x 6 ASTM C97-96

Water Absorption in Boil. Water (by volume) (%) (4x4x16 cm.) x 6 ASTM C 121-90

Density ( g/cm3) (4x4x16 cm.) x 6 ASTM E 12-70

Specific Gravity ( g/cm3) (4x4x16 cm.) x 6

Porosity (%) (4x4x16 cm.) x 6

Saturation Degree (%) (4x4x16 cm.) x 6

Water Vapour Transmission

(Diffusion resistance factor μ ) Diameter : Ø 7 cm. DIN 52615

Porosimetry (mercury intrusion) -

4.)Determination Of The Mechanical Properties

Tensile Strength (MPa) (4x4x16 cm.) x 6 ASTM C120-90

Compressive Strength (MPa) (7x7x7 cm.) x 6 ASTM C170-90

Static Elasticity Modulus (Ultrasound Method) (MPa) (4x4x16 cm.) x 6

Adherence Strength (Pull-off Method) (MPa) - TS EN 1542

Shrinkage (%) (4x4x16 cm.) x 6

5.)Ageing Tests

Freeze-Thaw Cycles (4x4x16 cm.) x 6

Salt Crystallisation Cycles (in %14 Na2SO410H2O) (4x4x16 cm.) x 6

68

3.3.3.1. Qualitative and Semi-Quantitative Analysis of the Water-Soluble Salts of the

Repair Mixes

Quantitative analysis of the water soluble salts and the conductivity tests were conducted on the

5th

C, medieval and 15th

C repair mortars after 1 month, 3 months and 6 months of curing time.

The total amount of soluble salts were evaluated by measuring their conductivities. For

conductivity tests a stock solution (1g. sample in 100 ml deionized water) was prepared and both

water soluble salts analysis by spot tests and conductivity measurements were carried on for each

sample.

Table 3.24. The results of the quantitative analysis of the water soluble salts and the conductivity

tests of the repair mortars

3.3.3.2. The Micro and Macro Analysis of the Repair Mortars

Petrology of the repair mortars after 3 and 6 months of curing time:

Fig. 3.92. General structure of phase between Fig. 3.93. The binding phase between two

aggregate and binder of the repair mortar of aggregates of the repair mortar of 5thC.

5thC. after 6 months of curing time after 6 months of curing time

Sample

5C1

5C2

5C3

M1

M2 M3

15C1

15C2 15C3

Cl-

++

++

++

++

++ ++

+

+ +

SO4-2

- -

-

-

-

-

-

-

-

CO3-2

- -

-

-

-

-

-

-

-

NO3

-

-

-

-

- -

-

- -

Conductance

(s) 348

1097

1481

123 1556

1786

72

1497

974

69

Fig. 3.94. The adhesion between the crushed Fig. 3.95. Binder , coarse aggregates (quartz

brick and the binder of the repair mortar of and brick pieces) fine aggregates (tuff dust)

5th

C. after 6 months of curing time

Fig. 3.96. General structure of the repair Fig. 3.97. A piece of tuff in the dusty form of

mortar of 5thC. after 3 months of curing time repair mortar of 5

th C. after 3 months of

curing time

Fig. 3.98. General structure of the medieval Fig. 3.99. Small feldspar particles in the matrix

repair mortar after 6 months of curing time. of the medieval repair mortar after 6 months

Brick piece on the left top of curing time

70

Fig. 3.100. Repair mortar for the repairs of Fig. 3.101. The binder and the crushed brick

the medieval parts after 6 months of curing particles in the matrix of the medieval repair

time. Small volcanic tuff pieces in the matrix mortar after 3 months of curing time

Fig. 3.102. General binding texture of the Fig. 3.103. General distribution of the

medieval repair mortar after 3 months of aggregates in the matrix of the repair mortar

curing time of 15thC. after 6 months of curing

Fig. 3.104. General distribution of the Fig. 3.105. The adhesion between the aggr.

aggregates (quartz and feldspar) and the (quartz and feldspar) and the binder of repair

binding phase of the repair mortar of 15thC. mortar of 15

thC. after 6 months of curing time

after 6 months of curing time

71

Fig. 3.106. The quartz and feldspar particles in Fig. 3.107. The adhesion between the crushed

the matrix of the repair mortar of 15thC. after brick and binder of repair mortar of 15

thC. after

6 months of curing time 6 months of curing time

Fig. 3.108. General structure of the repair Fig. 3.109. The tuff particles in the general

mortar of 15thC. after 3 months of curing time structure of the repair mortar of 15

thC. after

3 months of curing time

The textures of the 3 months old and 6 months old 5th

C. repair mortar samples seem to exhibit

similar features and they can not be distinguished in regard to their petrologies (Figures 3.92,

3.93, 3.94 and 3.95, 3.96). The textures of the lime pastes and the adhesion of it around the

aggregates, especially around the brick pieces were homogenous. Therefore it can be stated that

the setting of the mortar samples were homogenous and continuous. The phase differences

between quartz, calcite and volcanic tuff pieces were not observed. This fact was clear in the

texture of the sample which was given in Figure 3.97. Besides these good features, fissures were

also detected in the lime paste which were originating from the shrinkage stresses (Figure 3.92).

The mortar samples to match the properties of the medieval Byzantine mortars also displayed

similar textures to those of the 5th

C. A.D. repair mortars since the binder and the aggregates were

the same , where only the binder: aggregate ratios were slightly different (Figures 3.98, 3.99,

3.100, 3.101 and 3.102). The shrinkage fissures were slightly more than the aforementioned

samples.

The petrology of the 15th

C. A.D. repair mortars share the same features of the 5th

C. A.D. and

medieval repair mortars in regard to the homogenity of the lime paste except their colours were

paler as the samples included minor amounts of brick dust (Figures 3.103, 3.104, 3.105, 3.106,

72

3.107, 3.108 and 3.109). The aggregates were crushed tuff and tuff dust and river sand. The

shrinkage cracks between the aggregate and the binder interstices were in a minor amount which

can be neglected.The adhesion of the aggregates at their interstices with the lime paste can be

accepted as homogenous and well setted.

Results of the visual, macro and micro inspections and SEM-EDX analysis of the

repair mortars

Both macro and micro inspections were conducted on the repair mortars. The macro structure

photographs were taken by stereo microscope and the micro structure photographs were

taken by scanning electron microscope (SEM).

The repair mortar of 5th

Century;

X 1.8

Figure 3. 110. The macro structure of 5th C. Figure 3.111. Quartz and brick particles in

mortar and silicate formation at the interstice the lime paste

of the brick piece

Figure 3.112. The adhesion between the Figure 3.113. The adhesion between the

aggregate and the binder brick particle and lime paste and the

silicate formation at the interstice of the

brick aggregate and the lime paste

73

Figure 3.114. The micro crack in the lime paste Figure 3.115. The micro structure of the

and the secondary crystallisation in it lime paste

Figure 3.116. Secondary nanometer sized Figure 3.117. The micro structure of the

crystals in the lime paste lime paste, gel formation in the binder

(magnification of X 3500) (magnification of X 3500)

Figure 3.118. The binder / aggregate Figure 3.119. The adherence of the quartz

interstice and the matrix was poor due to the almost

non - porous micro structure of the quartz

aggregate

74

Figure 3.120. The adherence between the Figure 3.121. The binder / aggregate

aggregate and the lime paste interstice

Figure 3.122. Linescan display of 5 th

C. repair mortar

Figure 3.123. Linescan display of 5thC. repair mortar

Si

Ca

Al

Si

Ca

Al

Lime Brick

Al2O3 (tuff dust)

Brick CaO.SiO2

Lime Al2O3

75

Figure 3.124. Linescan display of 5thC. repair mortar

Figure 3.125. Linescan from the right (tuff dust cumulation) towards left (to the matrix),

sulphour, silicone and the calcium peaks, at the interstice, calcium diffusion was detected in the

tuff dust

Figure 3.126. Sulphour, silicone and the calcium profile

Al

Ca

Si

S

Si

Ca

S

Si

Ca

Lime

Quartz

Lime

CaO.SiO2.Al2O3 gel

formation

76

Figure 3.127. From the left to the right, silicone, calcium and aluminium peaks

The repair mortar for the medieval parts ;

Figure 3.128. The macro structure of the Figure 3.129. The adhesion between the

medieval repair mortar . Quartz and brick aggregates and the lime paste

particles in the matrix (macro structure)

Figure 3.130. The micro structure of the Figure 3.131. The micro structure of the

binder / aggregate interstice matrix

Si

Ca

Al

Lime Aggregate

77

Figure 3.132. Linescan display of M3 (medieval) repair mortar

The 15th

Century Repair Mortar ;

X1.8

Figure 3.133. The macro structure of 15th

Figure 3.134. Quartz and brick and volcanic

century repair mortar. Quartz and brick tuff particles in the lime paste

and volcanic tuff particles in the matrix

Figure 3.135. The adhesion between the Figure 3.136. The micro structure of the lime

aggregate and the binder and the shrinkage paste and the interstice of the brick aggregate

cracks

Si

Ca

Al

Lime Lime

CaO.SiO2

CaO.SiO2.Al2O3

78

Figure 3.137. The micro structure of the lime Figure 3.138. The micro structure of the

paste and the interstice of the brick aggregate lime paste

Figure 3.139. The micro structure of the Figure 3.140. The adhesion at the tuff dust

lime paste cumulation and the binder interstice, the

binder at the left and the tuff dust cumulation

at the right

Figure 3.141. The tuff dust cumulation and Figure 3.142. Brick piece (on the left), and

the silicate formation in the matrix and the the binder, the adhesion seems to be perfect

aggregates in the binder

79

Figure 3.143. Linescan display of 15th

C. repair mortar after 6 months curing time

Figure 3.144. Linescan display of 15thC. repair mortar after 6 months curing time

Figure 3.145. From the left to the right , sulphour , silicone and calcium peaks, the transition

zone at the interstice of the brick piece and the binder was exhibited in a diffusion profile

Si

Ca

Al

Si

Ca

Al

Si

S

Ca

Quartz Quartz

Brick

Lime Lime

Lime

Lime Aggregate

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