International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Volume XL-5/W2, 2013 
XXIV International CIPA Symposium, 2 — 6 September 2013, Strasbourg, France 
conservation regarding ^ vulnerability, or further 
development into risk indicator 
In this work a set of criteria, concerning both intrinsic and 
extrinsic risk factors and deriving from the protocol of advanced 
diagnostics, is selected and assigned with qualitative and 
quantitative designation to the risk. Within this process the 
simple criteria of risk analysis are further elaborated into 
transforming to risk indicators able to inform about an asset's 
resilience to various impacts and loads. 
The selection of certain parameters against other was mainly 
based on the fact that while some of them refer to the tendency 
of the materials to degradation and not necessarily to the actual 
state of preservation, others reflect the alteration of 
characteristics of weathered compared with healthy / quarry 
materials and therefore are more indicative of the degree of 
wear which have undergone and hold a greater weighing factor 
of the overall degradation process. It is therefore necessary to 
establish critical limits and the adoption of appropriate scale for 
each characteristic parameter to distinguish the range of values 
of each parameter in risk levels (level of risk) as to the state of 
the material (Chela, G., 2006). 
The selected parameters are: Microstructure characteristics 
alteration, Total soluble salts, Anions type and concentration, 
Visual observations — surface deterioration, Visual observations 
— qualitative, Ultrasonic velocity propagation, Environmental 
characterization, Architectural surface. 
The following step in the process of developing specific Risk 
Indicators (hereinafter denoted as RI) from these risk 
parameters requests the establishment of critical limits which 
determine whether deterioration level is accepted or not (Tables 
2-12). The scale applied is 1-5, 1 being the lowest limit and 5 
the highest limit. 
» Microstructure parameters variation (%) RII: 
concerns the parameters variation of decayed materials 
microstructure, like the total cumulative volume, bulk density, 
total open porosity and the average pore radius as well as 
specific surface area of the tested materials, in respect to healthy 
  
  
  
material. 
RI.1 1 2 3 4 5 
Total AV | 5<A | 8<A | 12<AV%<20 | 20<AV 
Cumula | %< | V% | V% % 
ted 5 <8 <12 
Volume 
(V%) 
Bulk Ad | 2<A | 3«A 5<Ad%<10 10<Ad 
Density | %< | d% | d% % 
(d%) 2 <3 <5 
  
Total AP S<A | S«A 12<AP%<20 20<AP 
  
Open | %< | P% | P% % 
Porosit 5 «8 | «12 
y 
(P%) 
Averag | Ar% | 1<A | 2<A 3<Ar%<5 5<Ar% 
e Pore <1 | r%< | rW< 
Radius 2 3 
(1%) 
  
Specific | ASS | 2<A | 3<A | 4<ASSA%<7 7<ASS 
Surface 
  
  
  
  
  
  
  
  
  
Area A% | SS SS A% 
(SSA%) | <2 | A% | A% 
<3 | <4 
  
  
  
  
  
  
  
  
Table 2. Microstructure parameters variation 
> Total soluble salts TSS% RI.2: concerns the 
concentration of total soluble salts, as an important decay 
risk indicator. The content is determined in respect to the 
material’s dry mass. 
  
  
  
  
  
  
  
  
RI.2 1 2 3 4 5 
TSS% | 33 3<T 4< 6< TSS%=<8 | TSS%>8 
SS% | TSS 
<4 %=6 
  
  
Table 3. Total soluble salts content 755% 
> Anions type and concentration Cl, SO; NO, RL.3: 
concerns the concentration of the main anions such as 
chlorides, sulphates and nitrates. The content is determined 
in respect to the material's dry mass. 
  
  
  
  
  
  
  
  
  
  
  
  
RI.3a 1 2 3 4 5 
ICH <0,3 | 0,3< | 0,4<C1 | 0,6<CI<0,8 0,8< 
(%) CI<0 | <0,6 Cl 
‚4 
[SO4] | <0,8 | 0,8< | 1<SO4 | 1,3<SO4<1.6 | 1,6<S 
(%) SO4 | <1.3 04 
<1 
[NO3] | <0,1 | 0,12 | ,20<N 0,35<NO3<0, | 0,5< 
(%) 2 «NO | 0O3«0,3 | 50 NO3 
3<0, | 5 
20 
Table 4. Quantitative determination of the anions ‘soluble 
fraction 
2 3 4 5 
t et opt oet 
RI.3b 
Cl 
1 
+ 
SO4 + ++ eb dope eet 
O3 =p 
d +++ +++ +++ 
  
Table 5. Semi quantitative determination of the anions 
“soluble fraction 
N 
» Decay patterns mapping RL4: concerns the surface 
decay mapping using various mapping techniques such as 
photography, photogrammetry etc., resulting to the in the 
quantification of micro cracks, crusts, exfoliations, 
detachments, alveolar decay, etc. This is achieved by 
estimating the percentage of the surface area occupied by 
each of the above decay types in relation to the appropriate 
weighting factor. 
  
  
  
  
  
  
RI.4 1 2 3 4 5 
Decayed <5 5<At | 15<At | 30<Atot | 50<Atot 
surface area ot%< | ot%<3 | %=<50 % 
(Atot%) 15 0 
  
  
  
Table 6. Estimated percentage area by each decay type