Maria BOSTENARU DAN

THE ECONOMIC IMPACT OF SEISMIC RETROFIT ON HERITAGE BUILDINGS WITH HISTORIC REINFORCED CONCRETE SKELETON STRUCTURE OF THE INTERWAR TIME

Maria BOSTENARU DAN

Overview

Introduction The building typology Performance levels and seismic retrofit

costs Building modelling Computation methodology Structural damage Comparison of costs Output for the decision system Outlook to further studies

The building typology

The RC skeleton building typology in Europe Studies of seismic countries: Romania,

Italy, Greece, Slovenia, Portugal (for the first two including archives)

Studies of other countries presenting the typology: Poland, Bulgaria, France, Czech Republic, Estonia, Austria, Netherlands, Spain, Germany (the last two moderate seismicity; Germany is steel frame)and of Art Nouveau forerunners (Belgium, Romania, Hungary, Estonia, Finnland, Germany) seehttp://bostenaru.natkat.org/project_results/study_trips.html

http://bostenaru.natkat.org/project_results/study_trips.html

http://bostenaru.natkat.org/project_results/study_trips.html

The RC skeleton among typologies in Bucharest, Romania Romanian housing typologies analysed (WHE&beyond)

Historic building with timbered balcony „wagon“ house (single story brick row) Two story brick masonry timber floor Multistory brick masonry steel composite floor RC skeleton (residential and mixed use) RC skeleton with RC braces Cast in situ RC structural walls (vulnerable and not) Precast RC structural walls Moment resisting RC frame multistorey (socialist) Moment resisting RC frame low rise (post 1989)

RC skeleton most vulnerable

Bucharest, Romania

Early RC skeleton

Building typology: Romania

Impact of apartment buildings bigger than any other housing Strong economy, private enterprise Deviations from mainstream movement

dicated by the market Condominium, like in Greece, until today Double entrance

Ottulescu building: free plan in an apartment block

Romania


Elena Ottulescu building, architect Horia Creangă, 1934-35

Bedroom/ nightzone

Livingroom, includingdinning

Corridors/ circulationzone

Bathrooms, toillets

Kitchen

Hall / vertical circulation

Deposit / external circulation

Legend:

Building typology: Italy

Two directions Rationalism (contextual Modernism)

Giuseppe Terragni Novecento

Decorative Geometrical

Novecento: function bound housing typologies, condominium

Zoning: function groups, double entrance


Giuseppe Terragni - Como

Photos 2005

Italy

Como


Giuseppe Terragni - Milano

Photos 2005

Italy

Milano Rationalist architecture: blue Novecento architecture: red


Novecento

Photos 2007


Novecento

Building in Via Domenichino, architects Lancia şi Ponti1928-30

Living room, dinning

Bathroom, toilets

Kitchen

Hall

Corridors / circulation zone

Deposit

Bedroom / Night zone

Building typology: Greece

1929 – ownership system for multistorey apartments

Housing in private hand, seen to be unique, but similar to Romania and Portugal

Training in Germany, little in France zonation

Zaimi and Stournary street example: „ressemble Italian rationalism“ – to be investigated

Double entrance

Building typology: GreecePhotos 2005

Greece

Athens

Greece

Bedroom/ nightzone

Livingroom, includingdinning

Corridors/ circulationzone

Bathrooms, toillets

Kitchen

Hall / vertical circulation

Deposit / external circulation

Legend:

building on Zaimi and Stournari streets, architects Valentis and Michailidis, 1933 – 1934

Slovenia

Few reinforced concrete skeleton multi-family housing

Joze Plecnik built housing programmes The multi-family housing by Plecnik can be

found in Vienna (ex. Zacherl house) Multi-family housing is mainly in brick Ljubljana was reconstructed after the 1895

earthquake mainly with buildings of Art Nouveau; Modernism and RC came later

Slovenia

Plecnik

Plecnik

In Austria skeleton photos 2005-

2006

Slovenia

Portugal

RC buildings in the north of the city, where avenues were built in the interwar time

Master Plan according to the 1933 Charter of Athens was done post-war

Traditional floor plans

Portugal

Cassiano Branco (photos 2005)

Portugal

Middle-agequarterAlfama

Baixa quarter built after the1755 earthquake

Haussmannian Boulevardbuilt before those in Paris

Performance levels and seismic retrofit costs

Performance levels and seismic retrofit costs Inspiration from studies in the theory of

daylight in atria Depending on the expected earthquake,

the measure can be more extensive or not

Adding a second window should be similar to adding a retrofit element and the distance to the amount

Moment of the measure

Extent of the measure

Extent of the measureCosts

ReparationRebuilding

Retrofit

Building modelling

Building modelling

Study of the structural typology of early RC Report for the WHE (extended

characteristics) Study of planimetry to identify typology of

distribution of spans and bays in a skeleton Modelling in the software

Building Retrofit measures

350mm

30mm

350mm

30mm

350mm

Steel bars anchored into the concrete to which the braces are fixed

Computation methodology

Computation methodology

Calculation using construction devices for „retrofit elements“ for Retrofit measures Repair measures after earthquake damage,

depending on damage degree (the software allowed to apply the retrofit method on a predamaged element) Computed following performance criteria available in

fibre based software Option for use of Project Management software

(considering all costs transformed in time) Calculation using surfaces for rebuilding the

building in case of total damage Use of MS Excell forms Option for use of new BIM software (2011)

Retrofit measure

Repair measure

After supervised work of Öztürk (2003)

Otpt No: 73 Time= 9,3360, spallig reached. Elm: Cb51ba. Unc Conc Strain = -0.002173 - G.p.(b)Otpt No: 73 Time= 9,3360, spallig reached. Elm: Cb2051a. Unc Conc Strain = -0.002116 - G.p.(b)Otpt No: 73 Time= 9,3360, spallig reached. Elm: C2031a. Unc Conc Strain = -0.002198 - G.p.(b)Otpt No: 73 Time= 9,3360, yield reached. Elm: C11bb. Steel Strain = 0.002502 - G.p.(a)Otpt No: 73 Time= 9,3360, yield reached. Elm: C2011a. Steel Strain = 0.002633 - G.p.(b)Otpt No: 73 Time= 9,3360, fracture reached. Elm: C2011b. Steel Strain = 0.069858 - G.p.(a)Otpt No: 73 Time= 9,3360, fracture reached. Elm: C2011b. Steel Strain = 0.109096 - G.p.(b)Otpt No: 73 Time= 9,3360, crush reached. Elm: C2011b. Conf Conc Strain = -0.007241 - G.p.(a)Otpt No: 73 Time= 9,3360, crush reached. Elm: C2011b. Conf Conc Strain = -0.04781 - G.p.(b)Otpt No: 73 Time= 9,3360, yield reached. Elm: C5011b. Steel Strain = 0.005749 - G.p.(a)

Typical log-file output

Otpt No: Time= reached Elm: Mat 1 Mat 2 Strain = Gauss point

1 0.1500, crack_cover bmz3412. Unc Conc 0.000107 G.p.(b) 1 0.1500, crack_core bmz2511. Conf Conc 0.000101 G.p.(a) 1 0.1500, crack_cover bmz2511. Unc Conc 0.000113 G.p.(a) 1 0.1500, crack_core bmz2512. Conf Conc 0.000108 G.p.(b) 1 0.1500, crack_cover bmz2512. Unc Conc 0.000122 G.p.(b) 1 0.1500, crack_cover bmz4411. Unc Conc 0.000101 G.p.(a) 1 0.1500, crack_cover bmz4412. Unc Conc 0.000109 G.p.(b) 1 0.1500, crack_core bmz3511. Conf Conc 0.000104 G.p.(a) 1 0.1500, crack_cover bmz3511. Unc Conc 0.000116 G.p.(a) 1 0.1500, crack_core bmz3512. Conf Conc 0.000111 G.p.(b)

Log-file output imported in MS Excell

ID Otpt No: Time= reached Elm: Mat 1 Mat 2 Strain = Gauss point

1 1 0.1500, crack_cover bmz3412. Unc Conc 0.000107 G.p.(b)

2 1 0.1500, crack_core bmz2511. Conf Conc 0.000101 G.p.(a)

3 1 0.1500, crack_cover bmz2511. Unc Conc 0.000113 G.p.(a)

4 1 0.1500, crack_core bmz2512. Conf Conc 0.000108 G.p.(b)




8 1 0.1500, crack_core bmz3511. Conf Conc 0.000104 G.p.(a)


10 1 0.1500, crack_core bmz3512. Conf Conc 0.000111 G.p.(b)

Log-file imported in MS Access

Gesamtsumme von ID yield crush spall crack_core crack_cover element

15 4 1 2 4 4 bmx121

14 4 2 4 4 bmx122

14 4 2 4 4 bmx133

14 4 2 4 4 bmx141

14 4 2 4 4 bmx142

10 2 4 4 bmx152

10 2 4 4 bmx153

10 2 4 4 bmx154

8 4 4 bmx161

8 4 4 bmx162

MS Access query

Structural damage

Structural damage

The method allows to count the damaged elements, and thus the costs for the entire building

The method also allows to localise the damaged elements

yieldingin beams

at 1st floor

yielding in beams at 4th floor

yielding in beams at 2nd

and 3rd floor

yielding in beams at 5th floor

crushing in ground floor

columns

spalling in first floor columns

spalling in ground floor

columnsNot retrofitted

Retrofitted with side walls

Retrofit method EQfracture+crush+spall+crack

yield+crush+spall+crack

crush+spall+crack

yield+spall+crack

spall+crack

yield+crack

crack only

None

1977 0,98 8,5 0 47,1 0 18,3 25,16

1986 0 0,7 0 19,9 1,0 1,0 77,45

1990, 1 0 0 0 0 0 0 65,7

1990, 2 0 0 0 0 2,0 7,2 88,6

1977+1977 3,27 14,05 0 45,75 0 16,01 20,92

1977+1986 0,98 9,15 0 44,12 0 19,93 25,82

1977+1990,2 0,98 9,15 0 44,44 0 19,28 26,14

1986+1990,1 0 3,92 0 17,32 1,63 9,74 47,39

Th.+Th. 0 0 0 0 0,98 0 97,71

Metal jacketing

1977 0 9,2 0 50,7 0,0 19,0 30,39

1986 0 2,6 0 20,9 2,0 28,8 45,75

1990, 1 0 0 0 0 0 0 66,3

Thessaloniki 0 0 0 0 0,98 0 97,71

Side walls

1986 0 0 1,2 0 0,6 0 62,3

1990, 1 0 0 0 0 0 0 64,0

1990, 2 0 0 0 0 0,6 0,3 88,3

Thessaloniki 0 0 0 0 1,75 0 96,78

1977+1977 0,58 10,53 0 63,16 0 10,53 15,2

1977+1986 0,88 8,19 0 50 0 19,93 21,64

1977+1990,1 0,88 8,19 0 39,47 0 13,45 31,87

1977+1990,2 0,88 9,06 0 38,89 0 16,67 28,65

1986+1977 0 4,09 0 16,08 0,29 23,1 48,83

1986+1977 0 7,02 0 53,8 0,29 18,13 20,76

Diagonal braces

1986 0 0 0 0 0 0 64,05

1990,1 0 0 0 0 0 0 54,25

1990,2 0 0 0 0 0 0 85,62

Structural wall

1990,1 0 0 0 0 0 0 56,36

1990,2 0 0 0 0 0,3 0 77,24

Comparison of costs

Comparison of costs

Done for Retrofit techniques (braces, jacketing,

structural wall, side walls) – seen earlier at % Retrofit strategies (amount and position of

braces) Compared for different earthquakes Compared with rebuild Computed the savings done in repair costs

by applying the retrofit before the earthquake, or before a second earthquake

Mod

el

Ret

rofi

t

Ear

thqu

ake

1

Ear

thqu

ake

2

Rep

arat

ion(

€)

Ret

rofi

t (€)

Tot

al(€

)

Reb

uild

(€)

Rep

arat

ion/

R

ebui

ld

Ret

rofi

t/

Reb

uild

T

otal

/ R

ebui

ld

Tot

al/

Reb

uild

-0,3

0 R

epar

atio

n/

Ret

rofi

t R

etro

fit/

R

epar

atio

n

Dif

fere

nce

to

not r

etro

fitt

ed

(€)

Rep

arat

ion

savi

ng/

retr

ofit

retr

ofit

/ R

epar

atio

n sa

ving

Gregor - 1977 - 406968 0 406968 3195391 0,13 0,00 0,13 -0,17 - 0 - - -

Gregor - 1986 - 432952 0 432952 3195391 0,14 0,00 0,14 -0,16 - 0 - - -

Gregor - 1990,1 - 271407 0 271407 3195391 0,08 0,00 0,08 -0,22 - 0 - - -

Gregor - 1990,2 376411 0 376411 3195391 0,12 0,00 0,12 -0,18 - 0 - - -

Gregor - 1977 1977 430400 0 430400 3195391 0,13 0,00 0,13 -0,17 - 0 - - -

Gregor - 1977 1986 398150 0 398150 3195391 0,12 0,00 0,12 -0,18 - 0 - - -

Gregor - 1977 1990,1 0 0 3195391 0,00 0,00 0,00 -0,30 - - - - -

Gregor - 1977 1990,2 401200 0 401200 3195391 0,13 0,00 0,13 -0,17 - 0 - - -

Gregor - 1986 1977 0 0 3195391 0,00 0,00 0,00 -0,30 - - - - -

Gregor Metal jacket 1977 - 445586 55152 500738 3195391 0,14 0,02 0,16 -0,14 8 0,12377395 38619 1 1

Gregor Metal jacket 1986 - 324031 55152 379183 3195391 0,10 0,02 0,12 -0,18 6 0,17020591 -108921 -2 -1

Gregor Metal jacket 1990,1 273885 55152 329037 3195391 0,09 0,02 0,10 -0,20 5 0,20136897 2479 0 22

Gregor Metal jacket Thessaloniki 408750 55152 463902 3195391 0,13 0,02 0,15 -0,15 7 0,13492844 0 -

Gregor Sidewalls 1986 299336 102960 402296 3195391 0,09 0,03 0,13 -0,17 3 0,34396188 -133616 -1 -1

Gregor Sidewalls 1990,1 295488 102960 398448 3195391 0,09 0,03 0,12 -0,18 3 0,34844055 24081 0 4

Gregor Sidewalls 1990,2 411170 102960 514130 3195391 0,13 0,03 0,16 -0,14 4 0,25040768 34759 0 3

Gregor Sidewalls Thessaloniki 457050 102960 560010 3195391 0,14 0,03 0,18 -0,12 4 0,22527076 0 -

Gregor Sidewalls 1977 1977 513400 102960 616360 3195391 0,16 0,03 0,19 -0,11 5 0,20054538 83000 1 1


Gregor Sidewalls 1977 1990,1 438650 102960 541610 3195391 0,14 0,03 0,17 -0,13 4 0,23472016 438650 4 0

Gregor Sidewalls 1977 1990,2 426400 102960 529360 3195391 0,13 0,03 0,17 -0,13 4 0,24146341 25200 0 4


Gregor Braces 1986 - 264600 87624 352224 3195391 0,08 0,03 0,11 -0,19 3 0,33115646 -168352 -2 -1

Gregor Braces 1990,1 - 224100 87624 311724 3195391 0,07 0,03 0,10 -0,20 3 0,39100402 -47307 -1 -2

Gregor Braces 1990,2 - 353700 87624 441324 3195391 0,11 0,03 0,14 -0,16 4 0,24773537 -22711 -0 -4

Gregor Structural wall 1990,1 - 251100 103622 354722 3195391 0,08 0,03 0,11 -0,19 2 0,41267224 -20307 -0 -5

Gregor Structural wall 1990,2 - 345950 103622 449572 3195391 0,11 0,03 0,14 -0,16 3 0,29952883 -30461 -0 -3

Mod

el

Ret

rofi

t

Ear

thqu

ake

1

Ear

thqu

ake

2

Rep

arat

ion(

€)

Ret

rofi

t (€)

Tot

al(€

)

Reb

uild

(€)

Rep

arat

ion/

R

ebui

ld

Ret

rofi

t/

Reb

uild

Tot

al/

Reb

uild

Tot

al/

Reb

uild

-0,3

0

Rep

arat

ion/

R

etro

fit

Ret

rofi

t/

Rep

arat

ion

Dif

fere

nce

to

not r

etro

fitt

ed

(€)

Rep

arat

ion

savi

ng/

retr

ofit

retr

ofit

/ R

epar

atio

n sa

ving

Özzi

1977 - 506950 0 506950 3123067 0,16 0,00 0,16 -0,14 - 0 -

1977 1977 526850 0 526850 3123067 0,17 0,00 0,17 -0,13 - 0 -

Thessaloniki - 422000 0 422000 3123067 0,14 0,00 0,14 -0,16 - 0 -

Thessaloniki Thessaloniki 423050 0 423050 3123067 0,14 0,00 0,14 -0,16 - 0 -

Özzi Braces 1

1977 - 544400 74785 619185 3123067 0,17 0,02 0,20 -0,10 7 0,1373719 0 0 6236566

1977 1977 595400 74785 670185 3123067 0,19 0,02 0,21 -0,09 8 0,12560507 0 0 3407139

Thessaloniki - 422000 74785 496785 3123067 0,14 0,02 0,16 -0,14 6 0,17721626 0 0 -

Thessaloniki Thessaloniki 479850 74785 554635 3123067 0,15 0,02 0,18 -0,12 6 0,15585133 0 0 4111961

Özzi Braces 2

1977 - 553050 67987 621037 3123067 0,18 0,02 0,20 -0,10 8 0,1229303 46100 1 1

1977 1977 605250 67987 673237 3123067 0,19 0,02 0,22 -0,08 9 0,11232813 78400 1 1

Thessaloniki - 67987 67987 3123067 0,00 0,02 0,02 -0,28 0 - -422000 -6 -0


Özzi Braces 3

1977 - 580950 67987 648937 3123067 0,19 0,02 0,21 -0,09 9 0,11702659 74000 1 1

1977 1977 606650 67987 674637 3123067 0,19 0,02 0,22 -0,08 9 0,1120689 79800 1 1

Thessaloniki - 473900 67987 541887 3123067 0,15 0,02 0,17 -0,13 7 0,14346191 51900 1 1


Özzi Braces 4

1977 - 455100 135973 591073 3123067 0,15 0,04 0,19 -0,11 3 0,29877653 -51850 -0 -3

1977 1977 596400 135973 732373 3123067 0,19 0,04 0,23 -0,07 4 0,22798994 69550 1 2

Thessaloniki - 345850 135973 481823 3123067 0,11 0,04 0,15 -0,15 3 0,39315657 -76150 -1 -2

Thessaloniki Thessaloniki 408900 135973 544873 3123067 0,13 0,04 0,17 -0,13 3 0,33253412 -14150 -0 -10

Özzi Braces 5

1977 - 176765 176765 3123067 0,00 0,06 0,06 -0,24 0 - -506950 -3 -0

1977 1977 586250 176765 763015 3123067 0,19 0,06 0,24 -0,06 3 0,3015184 59400 0 3

Thessaloniki - 176765 176765 3123067 0,00 0,06 0,06 -0,24 0 - -422000 -2 -0


Özzi - 1990,1 - 333461 0 333461 2808021 0,12 0,00 0,12 -0,18 - 0

Özzi - 1990,2 - 389594 0 389594 2808021 0,14 0,00 0,14 -0,16 - 0

Output for the decision system

Output for the decision system The costs have to be compared to the

benefits; benefits stay in first place Benefits can be compared among different

retrofit techniques and strategies, or compared to the status quo (no measure)

Comparison was done with two out of four identified methods: Pairwise comparison (costs are ranked

numerically) Utility value method (costs enter the

measurement spaces of some criterions)

Pairwise comparison method

Utility value method

Outlook to further studies

Optimisation of the current study Taking the prices for hour work for the country

from where the typology and the measures are (not always available; despite of flexible computation mean)

Making the computed curves to meet the one from the concept

Optimisation of measures for a given earthquake in order to make right computations

Employment also of probabilistic means to extend from the study cases to larger urban base

Comparison to the retrofit costs for a real building (soon envisaged through contact to offices; already done for stone masonry)

Studies of implemented retrofit measures Italy

FRP (Torre delle Nazioni, Napolo) Seismic dissipators (school Fabriano)

Romania Cutting of the corner <> new planimetry Jacketing

Greece Combined methods of FRP for horizontal

elements and jacketing for vertical elemens (Army Pension Fund building, hotel in northern Greece)

Relationship to earlier RC structures Pre-study of the distribution of

predecessors in Europe is already done Before RC skeleton the Hennebique

system was spread (after it was RC frame)

Differences and common features have to be put in connection

Relationship to timber

Preliminary research on a language for reinforced concrete from timber

Lessons to be learned from half-timbered housing for reinforced concrete A similar study of geografic distribution of

half-timbered construction Study of the bracing method for retrofit

Local seismic culture in reinforced concrete bracing

Computations for steel Realised projects with dissipators

Computer games

A method of training in the pre-disaster phase might be computer games

For the genre computer and management games there is an economic component, which can be derived from this research At urban scale: SimCity, also involving in the early

phases disaster scenarios such as 1906 San Francisco Earthquake

For building scale, see the games following the Ken Follett novels

Abstractisation of needed materials and people

Playing „World without End“

Construction and management games

Conclusions

Conclusions

An original methodology for computation of costs was developed, based on available project management methods and software possibilities

The method is aplicable for the single building (type) The building typology under study represents

heritage across Europe in seismic and non-seismic countries

An orginal concept of costs levels depending on expected earthquake was developed

It shows the value of planned conservation The costs have been put in the context of decision of

experts and larger participation in conservation efforts, part of which retrofit is

Acknowledgements

EFS Grant to attend this workshop

fellowship in frame of the DFG funded Research Training Network 450 “Natural Disasters” at the Universität Karlsruhe (TH), Germany (2000-2003)

Marie Curie Early Stage Research Host Fellowship, contract HPMT-CT-2001-00359, at the Istituto Universitario di Studi Superiori di Pavia, Italy (2002-2003)

Marie Curie Intra-European Fellowship, contract MEIF-CT-2005-009765, same host institution as above (2005-2007)

Marie Curie European Reintegration Grant, contract MERG-CT-2007-200636, at Foundation ERGOROM ´99, Bucharest, Romania (2007-2010)

Thank you!

Maria BOSTENARU DAN

Documents

Transcript of Maria BOSTENARU DAN