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
becoming risk indicators able to warn and advise about an
asset's susceptibility to degradation processes and therefore its
reduced strength.
1.3 Overview
In order to explore the current directives and methodologies
employed and applied in the field of risk assessment through
hazard identification and evaluation of a building’s
conservation state, an extended research was conducted, on
existing directives for risk assessment related to monument
conservation. The main objective was to become aware of the
identified hazards for monuments, the main vulnerability
attributes as well as the currently applicable risk assessment
methodologies. The outcome revealed that the risk of decay and
damage associated with monuments can not limited to certain
environmental dangers, static/structural, human impact and
natural hazards, but is also a function of various other factors
such as the conservation state of the materials (i.e. not only the
static/structural aspects of the building), the importance and
distribution of cultural heritage, the impact factor of the hazards
present, various socioeconomic parameters etc. Obviously,
these factors cover different scales of the problem. In particular,
there is a correlation between decay and damage of materials
that often leads to the monuments pathology. The deteriorating
processes in materials and structures may be triggered by
external influences or caused because of internal chemical
and/or physical time-depending variations of characteristics of
material. Therefore risk assessment should be dealt in the
direction of revealing the specific active decay mechanism with
an integrated decay study both in mesoscale [type of decay and
damage] and microscale [decay phenomenon mechanisms
(kinetics, thermodynamics, structural etc) (Moropoulou, et al
2012), (Kioussi et al., 2011).
2. METHODOLOGICAL APPROACH
A prerequisite for risk identification is the existence of an
organised source of reliable, comparable and interoperable data
about heritage assets under observation. In this framework the
identification and analysis of risks regarding degradation
processes for the development of qualitative and quantitative
indicators can be supported by integrated documentation.
Integrated documentation protocols assist proper data
collection, classification and presentation, enable understanding
and knowledge on the heritage asset (including its history, value
assessment, state of conservation, structural condition as well as
all previous restoration works, risks identification and
assessment of its vulnerability by environmental and human
causes) as well as monitoring and systematic reporting on
alterations taking place during its entire lifetime (Figure 1)
[Kioussi, et al 2013a].
More specifically, the protocols of advanced diagnostics, part of
the integrated documentation protocols, provide with the
guidelines for revealing the actual degradation processes
responsible for the asset's vulnerability, based on the
requirements of a typical diagnostic study and structural
analysis methodology, generated by a necessity for quality
control application in building and/or conservation materials
and structures and having been harmonized with appropriate
standards, in order to minimize structural faults, and enhance
effectiveness of conservation and protection interventions
(Figure 2) (Binda, et al, 2000), (Moropoulou, et al 2003),
(Kioussi, et al 2013b).
380
Figure 1. Integrated Documentation protocols data categories
I Visual Inspection (materials &
^ structure conservation state, decay
Pd & damage)
Diagnosis IL Non Destructive nt Fiber Optics Migroscpy-FOM
uz Ultra Sonic Tester
i Testing IB Gepradar -GPR
HE
ns
HI
ur
| Infrared Thepmegaphy - IR
Colonmeter
| Schmidt Hammer
| Digital Image processing
i nn
ur
I3
Hn
Ins
118
In?
Hg
IIS
1110
nni
Hn
n3
IIL Analytical Testing Porosimenry.
Capillary rise test
Moisture Index capacity
Drying Index
Granudometis analysis
FTIR (Fourier transforminfrared spectroscopy )
Differential Thermal Analysis and Thermogarimetric analysis)
Differential scanning calçrimetry (DSC)
Thermalmechanical gna;vsis (TMA)
Calcimetry
Total Soluble salts
Optical Microscopy
Scanning Electron Microscopy (SEM) with EDX (energy
dispersive Xray analvaisjanalysis
Polipzed microscopy
XRD (X-Ray Diffraction)
ma
ms
|
|
|
|
|
|
|
IV. Structural Analysis IVp!
IVp2
IVp3
Bearing structure
Damages
Permanent (dead)lcads
IVp4 Moving loads
IVpS Accidentalloads
IVpé Eigen period of structure
Ivp? Stress repetition period
IVp8 Type of foundation
Vp? Elements ngidity
plo Weight factor
IVpil Seismic rate
IVp12 Totalsesmic activity
IVp13 Simulation
IVpi4 Boundary conditions
IVpi5 Seismic zone
Figure 2. Integrated Protocols of Advanced Diagnostics data
categories and parameters
It is very important that the integration between the material’s
diagnosis and the overall documentation is taken into
consideration in order to identify the required levels of
preventive conservation and protection for heritage assets
depending on the most frequent local risks.
3. DEGRADATION PROCESSES
The detection of wear and degradation of building materials
includes the determination of decay products and damages. The
decay of building materials can be defined as the degradation
over time of the materials’ properties (physical, chemical,
mechanical, etc.) and characteristics (mineralogical, texture,
etc.), leading to their failure as building components. Decay
phenomena develop at the interface of materials with the
environment or at the interface of materials with other materials
and are a function of intrinsic and extrinsic factors. The analysis
of these factors is essential to the study of the decay pathology
of the monument and for the detection of the actual risks
affecting it (Moropoulou A., Labropoulos K., 2010)