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COMPDYN 2011 III ECCOMAS Thematic Conference on
Computational Methods in Structural Dynamics and Earthquake Engineering M. Papadrakakis, M. Fragiadakis, V. Plevris (eds.)
Corfu, Greece, 25–28 May 2011
RISK ASSESSMENT OF HISTORIC RESIDENTIAL BRICK-MASONRY
BUILDINGS IN VIENNA BY RAPID-VISUAL-SCREENING
Günther Achs1, and Christoph Adam
2
1 VCE-Holding GmbH Hadikgasse 60, 1140 Vienna, Austria
2 University of Innsbruck, Department of Civil Engineering Sciences Technikerstr. 13, 6020 Innsbruck, Austria
Keywords: Rapid-Visual-Screening, Damage scenario, Inspection form, Vulnerability esti-mation.
Abstract. In recent years the evaluation of risk levels of existing buildings by Rapid-Visual-
Screening (RVS) has become a common tool for seismic hazard assessment. If RVS is applied
to buildings of similar type located in a well-defined urban area, it is useful to specify and to
adapt existing screening rules and forms to the needs of these buildings. In a research effort
presented in this paper the RVS procedure is adapted for the seismic assessment of historic
residential brick-masonry buildings located in the City of Vienna, Austria. Considering the
consistent building typology the proposed RVS methodology enhances the validity and quality
of the seismic hazard assessment of this type of buildings. The evaluation and assessment
methodology is based on two parameters, i.e. the damage relevance DR, and the structural
parameter SP. Limiting conditions of the damage relevance DR are generated for risk classi-
fication to consider human and economic influence of damages on a certain building. The
structural parameter SP consists of several indicators to describe the condition of certain
structural parts of the building itself. In a large-scale in situ investigation a set of 375 build-
ings within the 20th
district of Vienna has been evaluated by the proposed methodology. The
results of this visual investigation are integrated into a local seismic building hazard map.
Günther Achs, and Christoph Adam
2
1 INTRODUCTION
1.1 Objective
Reliability of existing buildings against seismic collapse is a major issue of a comprehen-sive seismic hazard assessment. Particularly in urban areas with a huge amount of historic buildings the evaluation and assessment of those buildings is essential. In the city center of Vienna so-called Gründerzeithäuser, historic residential brick-masonry structures erected within the building phase between 1840 and 1918, represent the predominant type of building. Mostly, these structures have been retained unchanged without considerable structural im-provement for decades, but nevertheless are typically still used as residential buildings. Espe-cially the lack of information and scientific investigations about the material properties, the detailed construction, and the dynamic behavior of those buildings has led to many discus-sions about their vulnerability under seismic loading.
The main intent of the investigations proposed in this paper is to carry out a comprehensive assessment and evaluation methodology based on visual inspections for historic brick-masory buildings in Vienna in order to obtain a realistic estimation of the damage potential under seismic loading of this particular building type [1].
1.2 Prevalent Risk Assessment Methodologies
Several different methodologies for the assessment and classification of existing buildings were developed in the last few years [2]. Many of them, so called Rapid-Visual-Screening (RVS) techniques, are based on visual inspection of the buildings using predefined forms. Their main advantage is the fast and elementary implementation, which allows the user to evaluate a huge amount of buildings in a relatively short time period.
Particularly in areas with high seismicity the application of RVS techniques is widespread. One of the basic documents, developed and used in the United States of America, is the RVS technique described in the handbook for seismic evaluation of existing buildings by the Ap-plied Technology Council [3]. This method has already been used for years and is an impor-tant foundation for various international techniques. In particular the method is based on a scoring system, whereby different building parameters are classified and benchmarked.
Apart from the RVS procedures in the United States of America several other techniques have been developed in different countries. The Japanese technique [4] is based on the so-called Seismic Index (IS), which describes the resisting earthquake capacity of a story and is estimated from the strength and ductility of the building, the regularity of the building and a certain time index. In contrast, the RVS procedure in Canada accounts for structural parame-ters, such as the stiffness and the regularity of the building, as well as for nonstructural pa-rameters including the foundation of the building, building occupancy, importance of the building, and falling hazards. Compared to other countries, India has a very large amount of existing buildings of different types, which led to the development of different RVS proce-dures in the last few years [5, 6].
Most of the European RVS procedures were developed in Greece [7, 8] and in Turkey [9, 10, 11], whereby the investigated masonry buildings of the high seismicity area of Istanbul [12, 13] are of primary interest for the proposed RVS procedure developed for historic resi-dential brick-masonry buildings in Vienna.
The fundamentals of the procedure described in this paper were developed for historic ma-sonry buildings in Italy [14] and Portugal [15]. On the one hand, the assessment of brick-masonry facades can be directly applied by quantifying the building geometries [1, 14]. On
Günther Achs, and Christoph Adam
3
the other hand the connection of the damage relevance DR with damage grades from EMS-98 [16] according to Ferreira [15] gives a reliable estimation of the possible extent of losses.
Among the numerous other RVS procedures methods developed in Germany [17, 18] are of particular interest for the proposed RVS technique in Vienna, as they were applied on simi-lar historic buildings in areas with comparable seismicity.
2 APPLICATION TO HISTORIC RESIDENTAL BUILDINGS IN VIENNA
2.1 Basic Data
It was necessary to consider historic documents, such as building codes from the 19th cen-tury [19, 21, 22, 29] and findings from actual investigations [23, 24, 25], in order to develop a suitable RVS procedure for the historic residential brick-masonry buildings in Vienna. Par-ticularly in the last few years a guideline for the in-situ assessment for existing buildings was developed, mainly focused on the evaluation of the state of preservation of the structural sys-tem [24].
2.2 Inspection Form and Rating Methodology
As most of the international RVS procedures are focused on typical construction types, an adopted method with specific parameters for the historic residential buildings in Vienna had to be developed. The fundamentals for the evaluation and assessment methodology are based on two types of parameters to describe
- the damage relevance DR and - the structural parameter SP of the inspected building,
as shown in [26]. The damage relevance DR includes parameters to evaluate the social and economic influence of damages on a certain building. One of the main parameters of the dam-age relevance is the number of exposed persons within the inspected object. An overview on the content of the damage relevance DR and the description and quantification of several pa-rameters is presented in Table 1. The structural parameter SP mainly consists of single indica-tors to describe certain structural parts of the building itself. The most important parameters, which can be directly related to earthquake induced damage, are the regularity of the building in elevation and the state of preservation. The description of the structural parameter SP is given in Table 2.
To categorize and prioritize the buildings the combination of damage relevance DR and structural parameter SP is used to define hazard classes:
Hazard Class I: SP < 50 and DR < 50 Hazard Class II: 80 > SP ≥ 50 and DR < 100
or 100 > DR ≥ 50 and SP < 80 Hazard Class III: 140 > SP ≥ 80 and DR < 150
or 150 > DR ≥ 100 and SP < 140
Hazard Class IV: SP ≥ 140 or DR ≥ 150
Günther Achs, and Christoph Adam
4
The visualization of the conditions to define the hazard classes is illustrated in Figure 1.
Parameter Description Benchmarks
D01 Human
exposure
Number of endangered individuals within the in-spected object (estimation accepted in case of limited accessibility of the inspected object).
.01D No of Individuals=
D02 Importance
Importance of the inspected object according to [27], ranging from importance class I to IV.
D02 = 1.0 - 50.0
D03 Economic importance
Useable living area ULA multiplied by the potential price per m² and consideration of the remaining life time RLT of the inspected object.
03 100000 25
ULA Price RLTD
⋅
= ⋅
D04 Material
assets
Consideration of buildings with special purposes ranging from residential use (I), to archives and li-braries (II) and museums or churches (III).
D04 = 1.0 - 10.0
D05 Neighboring
effects
Assessment of possible effects due to collapsed build-ings or building parts, ranging from low exposure (I), to medium exposure (II) and high exposure (III).
D05 = 1.0 - 10.0
Damage Relevance 5
1
i
i
DR D
=
=∑
Table 1: Set of parameters describing the damage relevance DR.
Parameter Description Benchmarks
S01 Seismicity Evaluation of the seismic zone according to [28]. S01 = 1.0 - 1.5
S02 Regularity in plan
Classification of the regularity in plan according to [27] and a defined regularity in plan [1].
S02 = 1.0 - 10.0
S03 Regularity in elevation
Consideration of vertical irregularities with special attention on soft stories.
S03 = 1.0 - 100.0
S04 Type of construction
Evaluation of steel ties, masonry ceilings, etc. [1]. S04 = 1.0 - 25.0
S05 Local failure
Potential local failure mechanism of the facades of the inspected buildings [1] according to [14].
S05 = 1.0 - 20.0
S06 Secondary structures
Evaluation of exposed secondary structures [1] (chimneys, sculptures and statues of the façade, etc.).
S06 = 0.0 - 20.0
S07 Soil conditions
Assessment of the local soil conditions classified ac-cording to [27].
S07 = 1.0 - 10.0
S08 Foundation Classification of the foundation of the inspected building [1].
S08 = 1.0 - 10.0
S09 State of preservation
Evaluation of the state of preservation of the structure [1] (ceilings, columns, brick-masonry, etc.).
S09 = 0.0 - 30.0
Structural Parameter 9
1
i
i
SP S
=
=∑
Table 2: Set of parameters describing the structural parameter SP.
Günther Achs, and Christoph Adam
5
To simplify the visual screening of the building on-site a short inspection form was gener-ated [1]. The form should give the surveyor a step-by-step concept and support the inspection. After digitalization of the data several parameters were generated automatically.
Dam
age
Rel
evan
ce [
DR
]
DR = 100
SP
= 8
0
DR = 150
SP
= 1
40
DR = 50
SP
= 5
0
0
50
100
150
200
0 50 100 150 200Building Parameter [BP]
Hazard Class I
Hazard Class IV
Hazard Class III
Hazard Class II
Dam
age
Rel
evan
ce[D
R]
Structural Parameter [SP]
Figure 1: Visualization of the conditions to define the hazard classes.
2.3 Damage Estimation
The outcome of post-earthquake assessment reports was used to correlate the evaluated re-sults from the proposed RVS technique for historic residential brick-masonry buildings in Vi-enna with a possible damage behavior under seismic action. This method can be used if no particular vulnerability curves of the inspected buildings are available [15].
In a first step an earthquake event with similar characteristics like it is predicted for the Vi-enna basin area [29] related to magnitude, focal depth and site properties as well as adequate building stock was selected. From the past earthquakes the 2009 Earthquake, which hit the city of L’Aquila in the Abruzzo region in Italy, was chosen [30]. The description of damages occurred to historic residential masonry buildings after this event can be found in [30, 31]. The main outcome of the post-earthquake reports was that some of the proposed structural parameters for historic residential brick-masonry buildings in Vienna can be directly related to seismic damage. The most important ones apparently are the regularity in elevation, soft stories and the detailed design of connections between timber ceilings and bearing walls and of course the state of preservation of the affected building structure.
The comparison between damages occurred in L’Aquila [30, 31], the damage description of the EMS-98 Scale [16], which are given in Table 3, and the outcome of the RVS technique for historic residential brick-masonry buildings in Vienna led to the relations listed in Table 4.
Günther Achs, and Christoph Adam
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Grade Description of Damage Visualization
Negligible to slight damage
(no structural damage, slight non-structural damage)
1 - Hair-line cracks in very few walls
- Fall of small pieces of plaster only - Fall of loose stones from upper parts of buildings in very
few cases.
Moderate damage
(slight structural damage, moderate non-structural damage)
2 - Cracks in many walls
- Fall of fairly large pieces of plaster - Partial collapse of chimneys
Substantial to heavy damage
(moderate structural damage, heavy non-structural damage)
3 - Large and extensive cracks in most walls - Roof tiles detach - Chimneys fracture at the roof line - Failure of individual non-structural elements (partitions, ga-
ble walls).
Very heavy damage
(heavy structural damage, very heavy non-structural damage) 4
- Serious failure of walls - Partial structural failure of roofs and floors
Destruction
(very heavy structural damage) 5
- Total or near total collapse
Table 3: Classification of masonry buildings according to EMS-98 [16].
Therein several values of the assessment results, which were interpreted as boundary con-ditions for the proposed hazard classes, were related to predicted damage grades according to EMS-98 [16] and relevant structural conditions, which have to be fulfilled by the inspected object. It is obvious that buildings with high regularity in plan and elevation and a very good state of preservation, which were classified in hazard class I, should resist an earthquake simi-lar to the one occurred in L’Aquila [30] with moderate damages. On the other hand building structures with high irregularity in elevation and potential soft stories, which are generally in a poor state of preservation and therefore were classified in hazard class IV, might be predicted to show very heavy damages up to total destruction of the building under the exposure of the proposed earthquake. In between the buildings with slight or moderate irregularity in plan and elevation and moderate up to good state of preservation, which were classified into hazard classes II or III respectively, were predicted to show different grades of damage according to EMS-98 [16], ranging from moderate to very heavy damage.
Günther Achs, and Christoph Adam
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Hazard Class
Assessment requirements Structural Parameter SP Damage Relevance DR
Predicted Damage Grade
based on EMS-98
Relevant Structural Conditions
I
SP < 50 and
DR < 50 2
High regularity in plan and elevation; excellent state of
preservation
II
80 > SP ≥ 50 and DR < 100 or
100 > DR ≥ 50 and SP < 80 2-3
Slight irregularity in plan and elevation; good state of
preservation
III
140 > SP ≥ 80 and DR < 150 or
150 > DR ≥ 100 and SP < 140 3-4
Moderate irregularity in eleva-tion; subsequently removed bearing elements; moderate
state of preservation
IV
SP ≥ 140 or
DR ≥ 150 4-5
High irregularity in elevation; soft-story; in general poor
state of preservation
Table 4: Set of parameters describing the structural parameter SP.
3 APPLICATION
The developed RVS technique for historic residential brick-masonry buildings in Vienna has been calibrated by application to a set of buildings with very well known construction type, material behavior, and socio-economic parameters. These 18 buildings distributed across the historic city center of Vienna should represent a wide range of evaluation parameter pos-sibilities. A comprehensive description of those buildings, the results of the RVS technique application and outcome of the calibration are shown in [1].
After the calibration of the technique a large scale experimental investigation was per-formed. Therefore an adequate test area was chosen in the 20th district of Vienna with a set of 375 historic residential brick-masonry buildings. A site plan of the test area is shown in Fig-ure 2 with the inspected objects highlighted in red. It can be seen that the historic residential brick-masonry buildings are the predominant building type within the test area. In particular, whole blocks of buildings remained homogeneous since their erection in the 19th century.
3.1 Results
According to the developed RVS technique an engineer was trained on the characteristics of the methodology. The inspection of the buildings was performed continuously within a time period of three months. Besides the in-situ completed inspection forms where digitalized and analyzed. The comprehensive results of each inspected building and any evaluated pa-rameter can be found in [1]. In Figure 3 the results of the damage relevance DR plotted against the structural parameter SP of the large scale application is shown.
Günther Achs, and Christoph Adam
8
W
N S
O
Figure 2: Map of the test area in Vienna; inspected historic residential buildings (highlighted in red).
Dam
age
Rel
evan
ce [
DR
]
DR = 100
SP
= 8
0
DR = 150
SP
= 1
40
DR = 50
SP
= 5
0
0
50
100
150
200
250
300
0 50 100 150 200 250 300Structural Parameter [SP]
Hazard Class I
DR≤50 and SP≤50
Hazard Class II
80>SP≥50 and DR<100
or 100>DR≥50 and SP<80
Hazard Class III
140>SP≥80 and DR<150
or 150>DR≥100 and SP<140
Hazard Class IV
SP≥140 or DR≥150
Dam
age
Rel
evan
ce[D
R]
Structural Parameter [SP]
Figure 3: Results of the damage relevance DR plotted against the structural parameter SP of the large scale application.
Günther Achs, and Christoph Adam
9
It can be seen from Figure 3 that the results of the large scale experiment show a precise separation of hazard classes III and IV either in terms of the damage relevance DR or the structural parameter SP. Hence inspected objects classified in hazard class IV either have a comparatively high damage relevance DR, predominantly caused by the high number of ex-posed persons within the building, or have a very high structural parameter SP, which can be only generated by an irregularity in elevation.
According to Figure 3 most of the inspected objects were classified in hazard classes II or III, whereby no precise separation between those classes can be observed. The main reason for that is the high number of different parameters and hence the benchmarks of a single pa-rameter at a specific building may vary a lot.
The previously proposed methodology was used to correlate the results of the RVS as-sessment with predicted building damage, see section 2.3. In a first step the inspected objects were classified according to their structural parameter SP. Hence the damage grades accord-ing to EMS-98 [16] were correlated with the inspected buildings considering the scheme from Table 4, see Figure 4. It can be seen that the separation between damage grades 3 and 4 ac-cording to EMS-98 does not exactly correspond to the classification of the hazard classes II and III from Table 4. The reason therefore is that the frequency distribution of the structural parameter SP of the inspected buildings gives a better separation at SP = 100, instead of SP = 80 from Table 4. In general the direct correlation between hazard classes and damage grades according to EMS-98 seems to be problematic, as the damage distribution of different build-ings within a certain hazard class may vary, as already shown in Table 4. Nevertheless the correlation of the results from the RVS technique with EMS-98 damage grades offers a com-prehensive and fast prediction of the possible consequences of a certain earthquake. An illus-trative presentation of the results from the investigated test area is shown in Figure 5.
0
10
20
30
40
Bauwerks-parameter BP
Anzahl Objekte
20040 1901609080706050 120110100 150140130 180170
52 3 4
Damage Classification according to EMS-98
3
4
5
2
Insp
ecte
d B
uild
ings
Structural Parameter SP
Grade 2 (Moderate damage)
Grade 3 (Substantial to heavy damage)
Grade 4 (Very heavy damage)
Grade 5 (Destruction)
Figure 4: Correlation between damage grades according to EMS-98 [16] and the structural parameter of the in-spected buildings.
Günther Achs, and Christoph Adam
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Damage Grade according to EMS-98
Grade 2: Moderate Damage
Grade 3: Substantial to heavy damage
Grade 4: Very heavy damage
Grade 5: Destruction
Figure 5: Map of the test area in Vienna; results of the assessment of historic residential buildings and their cor-
relation with damage grades according to EMS-98 [16].
Günther Achs, and Christoph Adam
11
4 CONCLUSIONS
The Rapid-Visual-Screening (RVS) technique is a fast and widespread method for seismic hazard assessment of existing buildings. During the last few years a RVS technique for his-toric residential brick-masonry buildings in Vienna was adopted, due to the fact that those buildings represent the predominant type of constructions in the city center of Vienna and so far there was no information about their resistance against seismic actions.
The developed methodology to assess historic brick-masonry buildings consists of a visual inspection form and the subsequent evaluation of several parameters to capture the effects of possible damages to the environment and to describe and rate the structural behavior of the building. Furthermore the buildings were classified into certain hazard classes to prioritize the building stock by using the evaluated parameters.
Post-earthquake assessments from adequate past earthquake events have been used to cor-relate the results of the RVS technique with realistic seismic damages and hence EMS-98 damage grades were predicted.
In a large-scale investigation a set of 375 historic brick-masonry buildings were evaluated by the proposed methodology. The results of these tests could be integrated into a local seis-mic building hazard map.
The outcome of the proposed methodology supplies a good prediction of the damage dis-tribution within the test area. The evaluated hazard maps give useful information for emer-gency and evacuation planning as well as for identification of critical objects and further investigations.
ACKNWOLEDGEMENT
The investigations described were performed within the Austrian research project SEISMID [32], which aims among others to develop a methodology to assess the actual seis-mic bearing capacity of historic buildings. SEISMID is funded by the ZIT Center for Innova-tion and Technology, which is a subsidiary of the Vienna Business Agency (WWFF). This support is gratefully acknowledged.
Günther Achs, and Christoph Adam
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REFERENCES
[1] G. Achs, Seismic hazard of historic residential buildings. Evaluation, classification, and experimental investigations. (Erdbebengefährdung von Gründerzeithäusern. Berurteilung, Klassifierung und experimentelle Untersuchungen.) Doctoral Thesis (in German), Vienna University of Technology, to appear 2011.
[2] G.M. Calvi,R. Pinho, G. Magenes, J.J. Bommer, L.F. Restrepo-Vélez, H. Crowley, De-velopment of seismic vulnerability assessment methodologies over the past 30 years. ISET Journal of Earthquake Technology, 43, 75-104, 2006.
[3] Applied Technology Council ATC-21-1, Rapid visual screening of buildings for poten-tial seismic hazards: Supporting documentation. Applied Technology Council, 1988.
[4] JBDPA - Japan Building Disaster Prevention Association, Seismic Evaluation and Ret-rofit, Tokyo, Japan, 2001.
[5] S.K. Jain, K. Mitra, M. Kumar, M. Shah, A Proposed Rapid Visual Screening Procedure for Seismic Evaluation of RC-Frame Buildings in India. Earthquake Spectra, 26, 709–729, 2010.
[6] I. Gogoi, Rapid Visual Screening of Buildings in Assam. MAEE (Macedonian Associa-tion for Earthquake Engineering), 14
th European Conference on Earthquake Engineer-
ing (14th
ECEE), Ohrid, Macedonia, August 30 - September 03, 2010.
[7] OASP - Greek Earthquake Planning and Protection Organization, Provisions for Pre-Earthquake Vulnerability Assessment of Public Buildings (Part A), Athen, Greece, 2000.
[8] K. Demartinos, S. Dristos, First-level pre-earthquake assessment of buildings using fuzzy logic, Earthquake Spectra, 22, 865–885, 2006.
[9] Z. Sen, Rapid visual earthquake hazard evaluation of existing buildings by fuzzy logic modeling. Expert Systems with Applications, 37, 5653-5660, 2010.
[10] A.F. Hassan, M.A. Sozen, Seismic vulnerability assessment of low-rise buildings in re-gions with infrequent earthquakes. ACI Structural Journal, 94, 31-39, 1997.
[11] R. Ozdemir, B. Taskin, Seismic safety screening method for Istanbul Metropolitan City. 10
th East Asia Pacific Conference on Structural Engineering and Construction (EASEC
10), Bangkok, Thailand, August 3-5, 2006,
[12] M. Vatan, G. Arun, A method for assessing the risk level of monumental historical structures by visual inspections. MAEE (Macedonian Association for Earthquake Engi-neering), 14
th European Conference on Earthquake Engineering (14
th ECEE), Ohrid,
Macedonia, August 30 - September 03, 2010.
[13] M.A. Erberik, Seismic risk assessment of masonry buildings in Istanbul for effective risk mitigation. Earthquake Spectra, 26, 967-982, 2010.
[14] D. D’Ayala, E. Speranza, An integrated procedure for the assessment of seismic vulner-ability of historic buildings. ICE (Institution of Civil Engineers), 12
th European Confer-
ence on Earthquake Engineering (12th
ECEE). London, England, September 9-13, 2002.
[15] T. Ferreira, R. Vicente, H. Varum, Seismic vulnerability assessment of masonry facade walls. MAEE (Macedonian Association for Earthquake Engineering), 14
th European
Günther Achs, and Christoph Adam
13
Conference on Earthquake Engineering (14th
ECEE), Ohrid, Macedonia, August 30 - September 03, 2010.
[16] G. Grünthal, R. Mußon, J. Schwarz, M. Stucchi, European Macroseismic Scale 1998. Cahiers du Centre Européen de Geodynamique et de Séismologie, 15, 1998.
[17] K.H. Meskouris, H. Sadegh-Azar, H. Bérézowsky, R. Dümling, Fast assessment of seismic hazard of buildings (in German). (Schnellbewertung der Erdbebengefährdung von Gebäuden.) Der Bauingenieur, 7/8, 370 – 376, 2001.
[18] H. Sadegh-Azar, Fast assessment of seismic hazard of buildings (in German). (Schnellbewertung der Erdbebengefährdung von Gebäuden.) Doctoral Thesis (in Ger-man), RWTH Aachen University, 2002.
[19] Technical Building Code for Vienna, 1859, Regulation of the Ministry of the Interior, September 23, 1859, to enact a technical building code for the imperial capital and resi-dence city of Vienna, Journal of the provincial government of the Archduchy Austria below the river of Enns, Volume 1859, first division, part 52. Released and dispatched on October 15, 1859, Imperial-royal national press, Vienna (in German). (Bauordnung Wien, 1859. Verordnung des Ministeriums des Innern vom 23. September 1859, womit eine Bauordnung für die k.k. Reichshaupt- und Residenzstadt Wien erlassen wird, Landes-Regierungsblatt für das Erzherzogthum Oesterreich unter der Enns, Jahrgang 1859. Erste Abtheilung. LII. Stück. Ausgegeben und versendet am 15. Oktober 1859. Wien: Kaiserlich-Königliche Hof und Staatsdruckerei.)
[20] Technical Building Code for Vienna, 1869, Regulation of the Ministry of the Interior, December 2, 1868, to enact a technical building code for the imperial capital and resi-dence city of Vienna, Journal of the provincial government of the Archduchy Austria below the river of Enns, Imperial-royal national press, Vienna (in German). (Bauordnung Wien, 1868. Landesgesetz vom 2. Dezember 1868, womit eine Bauordnung für die k.k. Reichshaupt- und Residenzstadt Wien erlassen wird. Landes-Gesetz- und Verordnungsblatt für das Erzherzogthum Oesterreich unter der Enns. Wien: Kaiserlich-Königliche Hof und Staatsdruckerei.)
[21] Technical Building Code for Vienna, 1883, Regulation of the Ministry of the Interior, January 17, 1883, to enact a technical building code for the imperial capital and resi-dence city of Vienna, Journal of the provincial government of the Archduchy Austria below the river of Enns, Part 12, Regulation 35, Imperial-royal national press, Vienna (in German). (Bauordnung Wien, 1883. Bauordnung für die k.k. Reichshaupt- und Residenzstadt Wien. Gesetz vom 17. Jänner 1883, Nr. 35. Landes-Gesetz- und Verordnungsblatt für das Erzherzogthum Oesterreich unter der Enns, XII. Stück. 35. Gesetz. Wien: Kaiserlich-Königliche Hof und Staatsdruckerei.)
[22] Municipality of Vienna, Technical building code for the imperial capital and residence city of Vienna, January 17, 1883, Journal of the provincial government of the Arch-duchy Austria below the river of Enns, Regulation 35, and Regulation of December 26, 1890, Journal of the provincial government of the Archduchy Austria below the river of Enns, Regulation 48, including instructions for officials of the urban building authority for the execution of the technical building code for Vienna, released on January 17, 1883. Private publishing venture, Vienna (in German). (Magistrat Wien, 1892: Bau-Ordnung für die k.k. Reichshaupt- und Residenzstadt Wien; Gesetz vom 17. Jänner 1883, L.-G.-Bl. Nr. 35 und Gesetz vom 26. December 1890, L.-G. u. V.-Bl. Nr. 48; inkl. Instructionen für die Beamten des Stadtbauamtes bei Handhabung des Baugesetzes für
Günther Achs, and Christoph Adam
14
Wien vom 17. Jänner 1883. Im Verlage des Magistrates, Druck von Johann R. Bernah der Stadt Wien.)
[23] R. Flesch, W. Lenhardt, R. Geier, Earthquake induced damages in Austria - Assessment of existing buildings (in German). (Schadensbeben in Österreich - Beurteilung bestehender Bauwerke.) Bautechnik, 82, 533-538, 2005.
[24] ÖIBI, Special seminar “Engineer Diagnostics” (in German). (Spezialseminar Ingenieur-befund.) Course Material, Ingenieurbefund (in German), Vienna University of Technol-ogy, 2009.
[25] B. Rusnov, Analysis of buildings vulnerable to earthquakes with empahsis on old and historic buildings. (Analyse von erdbebengefährdeten Bauwerken mit dem Schwerpunkt auf alten und historischen Gebäuden.) Doctoral Thesis (in German), Vienna University of Technology, 2006.
[26] SIA, Assessment of existing buildings with respect to earthquakes. (in German). (Überprüfung bestehender Gebäude bezüglich Erdbeben.) Technical Note 2018, Swiss Society of Civil Engineers and Architects, Zurich, Switzerland, 2004.
[27] European Committee for Standardization - Eurocode 8, Design of structures for earth-quake resistance - Part 1: General rules, seismic actions and rules for buildings, Techni-cal Building Code ÖN EN 1998-1 (in German), Austrian Standards plus inc., 2005.
[28] European Committee for Standardization - Eurocode 8, Design of structures for earth-quake resistance - Part 1: General rules, seismic actions and rules for buildings, Na-tional specifications concerning ÖNORM EN 1998-1 and national comments, Technical Building Code ÖN B 1998-1 (in German), Austrian Standards plus inc., 2006.
[29] R. Hinsch, K. Decker, Do seismic slip deficits indicate an underestimated earthquake potential along the Vienna Basin Transfer Fault System? Terra Nova, 15, 343–349, 2003.
[30] O.C. Celik, H. Sesigur, Performance of historic masonry buildings during the April 6, 2009 L’Aquila Earthquake. MAEE (Macedonian Association for Earthquake Engineer-ing), 14
th European Conference on Earthquake Engineering (14
th ECEE), Ohrid, Mace-
donia, August 30 - September 03, 2010.
[31] J.E. Alarcon, G. Franco, P. Bazzurro, M. Simic, The L’Aquila (Abruzzo) earthquake of 6th April 2009 - Field survey and loss estimation. MAEE (Macedonian Association for Earthquake Engineering), 14
th European Conference on Earthquake Engineering (14
th
ECEE), Ohrid, Macedonia, August 30 - September 03, 2010.
[32] SEISMID, Seismic System Identification, Austrian research project, funded by the ZIT Center for Innovation and Technology, Vienna.
