Upload
hoangkhanh
View
221
Download
0
Embed Size (px)
Citation preview
Reverse Engineering of Historical Mortar and Plaster
- Ecofriendly Construction Materials -
Royal Botanic Garden1st Annual Scientific Day
Thursday January 12, 2012Amman, Jordan
Dr. Ayoup M. GhrairDr. Adi Said, Eng. Nailah al-Dawod,
Dr. Riham Miqdadi, Eng. Kamal Nuimat
Introduction• Natural and human factors have caused rapid
degradation in architectural heritage. As well as,some conservation projects at various historicalsites have had a negative impact on archaeologicalvalues because incorrect materials and techniqueswere applied during the conservation process.
• This project focuses on Reverse Engineering ofHistorical Mortar and Plaster to be used asecofriendly construction materials in greenbuildings and conservation applications.
IntroductionMortar types
- Lime mortar (hydraulic or non hydraulic) is one of theoldest known types of mortar, dating back to the 4thCentury BC and widely used in Ancient Rome and Greece
- Gypsum mortar is common to Ancient Egyptianconstruction
Plaster types- Lime plaster
- Gypsum plaster
Objectives• Study the composition of original mortars and
plasters to reconstruct their recipes
• Develop duplicate mortars and validate theirapplicability in the laboratory and on-site tests
• Establish standard specifications for mortars ofeach site
• Establish a permanent conservation team andtrain workers group from the local community intraditional mortar and plaster techniques
Figure 1. Mshash cistern, inner face plaster
Figure 4. Al-Tuba castle, anhydrous gypsum mortar
Figure 3. Different colors of fired bricks Mar-Elias Church southwells
Figure 2. Mshash cistern, infilling mortar
Petrographic Study
XRD Mineralogy study
Figure 1. XRD Spectra for Mar-Elias Church, well plaster.
Figure 2. XRD Spectra for Al-Tuba castle, upper part mortar
Figure 3. XRD Spectra for Al-Tuba castle, lower part mortar
Figure 4. XRD Spectra for Mshash castle, outer face plaster.
Table 1. Picking minerals under anoptical microscope
Inclusions
Inner layer
Plaster %30
Outer layer
Plaster %29
Grog 15 46
Aggregate 57 19
Lime 25 35
Charcoal 0.3 0.2
Quartz (Sand) 3 0.1
Total 100%
Table 2. Chemical analyses of total elements, acid soluble elements, losses at various temperatures for plaster and mortar samples
Element
(%)
Al-Tuba Castle
Lower part
Mortar
25
Al Tuba Castle
Upper part
Mortar
28
Mar-Elias church
wells plaster
24
Mar Elias
Church
Grave yard
Plaster
31
Mshash Cistern
Outer face
Plaster
29
Mshash Cistern
Inner face
Plaster
30
SiO2 7.06 19.11 17.3 6.65 19.58 16.70
Al2O3 1.19 2.10 4.23 0.80 3.73 2.12
Fe2O3 0.48 0.91 1.23 0.27 1.00 1.11
TiO2 0.09 0.19 0.28 0.19 0.21 0.20
P2O5 1.86 1.13 0.10 -- 0.37 --
CaO 34.24 32.78 39.72 49.60 43.19 42.65
MgO 0.56 1.23 0.6 0.43 0.64 0.80
Na2O 0.06 0.0 0.07 1.48 0.06 0.09
K2O 0.13 1.35 0.11 0.11 1.81 1.93
SO4 26.02 3.35 0.74 0.91 2.54 0.90
Loss at 105oC 0.91 5.58 1.12 1.34 0.89 1.12
Loss at 250oC10.84 5.74 2.26 1.59 1.71 1.80
Loss at 500oC15.50 16.39 6.84 4.02 4.72 5.22
Loss at 650oC20.13 28.45 17.45 15.57 17.80 14.20
Loss at 1000oC 22.73 35.36 36.03 39.03 33.09 34.32
Expected Outcome
By the end of the time framework designed for thefirst phase of this research, the following results areto be expected:
• Establishment of standard specifications for themortar of each site
• Durability and improved efficiency in repairingmortars in our architectural heritage
• Creation of a fully trained restoration team
Conclusion and Outlook
Mixes Lime Grog Gypsum Aggregate Sand Carbon&Ash
Mix 1 15 5 60 10 5 5
Mix 2 25 10 0.0 15 45 5
Mix 3 30 15 0.0 40 10 5
Mix 4 Will be designed
Mix 5 Will be designed
Proposed mixes of various materials estimated from the chemical analyses of total elements, acid soluble elements, losses at various temperatures and material balance calculations.
The final evaluation of the mortar and plaster will be done based on Bottger (1997), Knofel and Huesmann (1993) and Omeri (2009).)
Compressive strength ≥ 1.5 N/mm2
Tensile strength > 0.2 N/mm2
Elasticity modulus < 10 N/mm2
Water absorption < 10 kg. m-2.h-0.5