לארשיב תשרומ ירתא Examples of analysis and interventions ... studies on... · Deterioração das pedras do arco Fendas na separação dos panos de alvenaria Fendas

המועצה לשימור

אתרי מורשת בישראל

Examples of

analysis and

interventions :

Case studies on

monuments

Paulo B. Lourenço

[email protected]

www.civil.uminho.pt/masonry

Institute for Sustainability and Innovation in Structural Engineering

2 | Examples of analysis and interventions : Case studies on monuments Paulo B. Lourenço

Applications (I)

Mosteiro dos Jerónimos Mosteiro de Salzedas Sé do Porto Convento Tomar



Applications (II)

3.21

14.30

1.4

5

3.61

2.1

4

2.83

4.68

3.89

1.9

6

1.7

4

7.82

5.98

2.75

0.55

8.97

3.0

8

0.81

4.41

3.8

5

3.41

3.35

2.6

8

1.33

14.29

1.32

8.1

4

2.58

6.62

3.1

3

3.3

7

3.5

5

3.5

0

F12.2

3

0.3

5

6.83

2.86

1.28

1.24

1.41

2.77

1.1

9

1.1

9

2.5

81.4

5

1.4

4

2.84

1.37

1.42

2.76

6.2

5

1.4

6

8.39

3.3

4

3.3

4

3.3

4

3.5

4

3.5

4

3.4

5

3.5

5

1.2

5

3.4

5

3.3

4

2.01

2.01

0.54

2.43

1.44

0.44

T

T

*

Deterioração das

pedras do arco

Fendas na separação dos

panos de alvenaria

Fendas na chave das

abóbadas

Qutb Minar, India

Pontificial defense,

Italy

Famagusta

Churches, Cyprus

Canterbury

Cathedral, UK

Safi and Mazagan, Morroco



Cathedral of Porto (I)

South Tower

North Tower



Cathedral of Porto (II)

Tirantes

2 x 25mm

Por cima do vão

tamponado

Legenda:

Fendas existentes a monitorizar

No vão inferior

Escala:

0.0 2.5 5.0 m1.0

Corte AA Corte BB

E1 e E2

F3

F4

C2

TS2

TH

C1 F2

D

F1

TS1

Monitoring

Advanced structural analysis

Non-destructive testing



Cathedral of Porto (III)



Iglesia de San Cristóbal, Cusco (I)

Origin1560 (18th century)



Iglesia de San Cristóbal, Cusco (II)



Iglesia de San Cristóbal, Cusco (III)



Iglesia de San Cristóbal, Cusco (IV)



What not to do (I)?

The need to understand materials, structural

arrangements and constriuction techniques

from existing buildings



What not to do (II)?

It is necessary to adopt adequate safety evaluation

procedures (history, quantitative analysis, qualitative

analysis, experimental analysis)



Applications



Igreja da Imaculada

Conceição /

Immaculate

Conception Church,

Braga



(Igreja)

1,50 m

1,2

0 m

3,0

0 m

1,50 m

1,2

0 m

15,90 m

9,1

5 m

0,85 m

1,4

5 m

Description (I) Church dates from 1625. Currently an institute for abandoned

or mistreated girls, providing lodging and education

Choir: Original floor in chestnut. Masonry walls with 1.2m

thickness. Timber roof with timber lining. Openings with 1.5 to

3.0m width.

Floor with a span of 9.15m. Main beams with 300x300mm2

section and secondary beams with 65x100mm2. Beams for

floor planks with 65x65mm2 (eucalyptus). Floor planks with

30mm thickness and 300 / 400mm width (chestnut and pine).

Steel tube struts with a external diameter of 49mm, placed at

the thirds of the span



Safety assessment and strengthening of the choir (The floor exhibits

significant deformation, change of use for museum)

(Igreja)

Vigamento principal

Vigamento secundário Travessas

Escoras metálicas

500 mm 500 mm 500 mm

65

mm

300 mm

10

0 m

m65 mm

10

0 m

m3

0 m

m

30

0 m

m

44

0 m

m

15

0 m

m

65 mm

500 mm 500 mm 500 mm

65

mm

300 mm

10

0 m

m65 mm

10

0 m

m3

0 m

m

30

0 m

m

44

0 m

m

15

0 m

m

65 mm



[resi]

[mm]

380360340320300280260240220200180160140120100806040200

600

550

500

450

400

350

300

250

200

150

100

50

0

Structure in good condition



30

0 m

m3

00

mm

22

2 m

m

80

mm

14

0 m

m1

60

mm

30

mm

Perfil HEB300

500 mm

Perfil UNP80

67

0 m

m

10

0 m

m65 mm

Perfil HEB140

300 mm

300 mm

10

0 m

m

30

0 m

m

30

mm

65 mm

65

mm

44

0 m

m

15

0 m

m

500 mm

10

0 m

m

Strengthening proposal A

300 mm

60 m

m

300

mm

30 m

m

250 mm250 mm

500

mm

150

mm

500 mm

100

mm65 mm

Perfil HEM140Localização do

antigo soalho 250 mm

Localização das novas vigas

secundárias em castanho

300 mm

60

mm

30

0 m

m

30

mm

250 mm250 mm

50

0 m

m

15

0 m

m

500 mm

10

0 m

m65 mm

Perfil HEM140Localização do

antigo soalho 250 mm

Localização das novas vigas

secundárias em castanho

Strengthening of

the secondary

beams and

addition of a

steel profile

Cost = 1.32

Strengthening proposal B Strengthening proposal C

Strengthening of

the secondary

beams and

steel struts

Cost = 1.00

Keep only main

beams.

Code live load

Cost = 3.82



Chimney of Arouca Monastery



Geometry

Aspects chimney: In plan size of 4.3 x 4.1 m2 and 16.2 m height

Geometry and internal arching system

aprox. 0.40m

aprox. 0.15m

Cross-section

reduction



Existing Damage

Details of cracking in the supports

Cracking in the front wall and left wall

Corrosion Corrosion



Numerical Analysis (I)

Two models

(with and without arching action)

Elastic results with arching action:

st,max = 3.5 N/mm2

Elastic results without arching action:

st,max = 6.2 N/mm2

N = 58.5 kN

N = 102.3 kN



Numerical Analysis (II)

Cracking in transverse beams

Crushing

0.0 -0.4 -0.8 -1.2

Deslocamento vertical [mm]

0.0

0.5

1.0

1.5

2.0

2.5

Fac

tor

de

carg

a [-

]

Vertical displacement (mm)

Lo

ad

Facto

r (-

)

Load-displacement diagram

Cracking

Most conservative model



Conclusions and remedial actions

Cracks in main lintel and one side lintel. Corrosion in the ties.

Original building defects: asymmetric positioning of the main arch; possible lack of

separation between arch and masonry infill; progressive cross-section reduction of

the cracked side lintel.

Numerical analysis indicates that the collapse of the main lintel is not due only to

structural reasons. Corrosion might be the precursor of failure. For a loading factor of

2.0, collapse of the side lintel could be expected in the most unfavorable conditions,

but not the main lintel.

A crack did occur in the side lintel with the cross-section reduction and new columns

have been added to the structure. The cross-section reduction has not been

considered in the computer simulation.

Varões

pré-esforçados

Chapas

metálicas Chimney can be used for firing exceptionally.

Corroded ties must be replaced by stainless

steel. Other ties are to be depassivated and fire

protected.

Two possible remedial measures: (a) glue stone

with epoxy resin and inner strengthening, drill a

long hole and insert post-tensioned bars; (b) lift

chimney and replace stone by a new (selected)

one

Steel plates

Post-tensioned

bars



Numerical Analysis (I)

Two stainless

Steel bars

(25)

Anchoring plates

Stone topper

Granite

Stainless

steel

Fluid

mortar

Rendering









Monastery of Salzedas



Brief historical

review



Typical Cistercian Abbey. Considerable size in plan, 75.0 101.0 m2. Origin from the XII

century.

Cloister from the 17th century. Classical model with columns and closed upper gallery. Ribbed

crossed vaults in the first floor and cannon vaults in the second floor.



Context

Portugal 1834: the new political system, of liberal and constitutional origin,

decides the extinction of religious Orders, confiscates their properties and

sells them in auction. Monastery of Salzedas was left abandoned with

demolitions, stealing, ruined or in the verge of collapse parts.

Nature slowly taking care of the site. No “restoration”. Unfinished works.

A harmonious disorder where everything evokes “time”. A time of multiple

pasts felt in each single part of the building: the scars, the clear vestiges from

other eras, the unexpected shapes of the incomplete and the empty.

General actions: (a) Cleaning – removal of biological infestation, and removal

and selection of debris with the archaeological assistance, from which a set of

stabilized and stored elements and fragments resulted; (b) Consolidation – of

the parts considered at risk; (c) Protection – stopping, even if with temporary

system, infiltration of rainwater; (d) Access creation – reinstate, using

permanent, or temporary structures, the horizontal and vertical

communications lost; install scaffolding for inspection; (e) Geometrical

Survey – of the entire compound; (f) – Inventory and Conservation – for

movable heritage.



• Stop tourist visits

• Protect against rainwater infiltration

• Urgent measures in the cloister

• Moderate funding

• Decision: To preserve the ruin (or

keep the aesthetics of time). Present

intervention would be as much

effective, as it would remain invisible

• Further action once a global

compound strategy is decided

Step 1

Step 2

Step 3

Actions in the main cloister



Situation found

D E

A

B

C

Replacement of the barrel vault of the

West wing

Dismantling and reassembly of

the wall between the small and

the large cloisters

A – Church

B – Sacristy

C – Chapter room

D – Main cloister

E – Small cloister



Damage survey



Main cracks (I)

First floor – crossed vaults Second floor – barrel vaults



Main cracks (II)

South wing at the 2nd level

South-West corner

at the 2nd level

West wing at the 1st level

South-West corner

at the 1st level



Limited cracks

in the walls

Internal wall of the West wing

External wall of East wing External wall of South wing



Separation between vaults and walls

Out of plumbness of walls (2nd level). Resulted in

vertical displacements in vaults’ extrados up to 0.10 m

Large movements in the cloister’s internal walls



Other damage

Crushing / shearing of

brackets

Deterioration of bricks

Stone deterioration Biological colonization and moisture stains



Stone deterioration mapping and study on salts



Highlights of

structural survey,

NDT and

numerical

analysis



Aspect of

column

foundation

s

Embankment

Organic soil

Alluvial soil with stones

Alluvial stones with pebble

Granular soil with clay

Large stones

Soil foundation exhibits moderate resistance and very large

heterogeneity for depths between 1.0 and 1.8 m

Aspect of

wall

foundation

s

Foundation inspection pits



Tests on walls and vaults (I)

The vaults are built with clay brick masonry with 0.22m thickness and infill

(soil in 1st level and lime “concrete” in the 2nd level)

The walls are built with large granite stones, mostly with clay mortared

joints

Internal longitudinal cracks or voids were not found

Low strength and high porosity bricks (compressive strength 5 N/mm2)



Tests on walls and vaults (II)

Samples for the uniaxial

compression tests Eb = 7.3 GPa fb = 5.2 MPa

Em = 8.6 GPa fm = 3.8 MPa



Structural analysis (Linear Elastic)

Deformation of

the structure Maximum principal

stresses Minimal principal

stresses

• The large horizontal displacements observed in the structure can only be explained by a

geometrical and physical non-linear analysis

• The 3D model served also for validation of a simplified 2D model (only of the 2nd floor)

• The structure presents original conceptual deficiencies (insufficient buttressing in internal

walls)



Non-linear analysis

0.0

0.2

0.4

0.6

0.8

1.0

1.2

0.0 1.0 2.0 3.0 4.0

Deslocamento (cm)

Facto

r d

e c

arg

a

Horizontal

Vertical

Damage in the barrel vault

Damage in all the entire

structure

Displacement (cm)

Lo

ad

fa

cto

r

Relation between the load factor and the

displacements exhibited by the structure

(“zero safety level”)

•Foundations and long term behaviour

of the structure are mostly

responsible for observed damage

•Strengthening is needed



Execution details



Remedial measures

Reforço

com CFRP

Inclinação do pavimento = 1.0%

Inclinação do pavimento = 2.5%Lajeado em pedra a repor

Adjustable propping

Partial removal of infill (2 wings in 2nd level)

Partial removal of infill (2 wings in 1st level)

Elevation of 2 wings (1 in each level). 10 cm

Pulling of one corner. 12.5 cm

Local protheses in stone brackets / ribs

Repointing and injection of cracks and

joints in vaults

Stainless steel ties

Water tightening of 2nd level

Repointing joints in the external walls

Closing of openings



Reforço

com CFRP



Reforço

com CFRP



Reforço

com CFRP





2nd Level



Piso 2 U

NIV

ER

SID

AD

E D

O M

INH

O

DE

PA

RT

AM

EN

TO

DE

EN

GE

NH

AR

IA C

IVIL



1st Level U

NIV

ER

SID

AD

E D

O M

INH

O

DE

PA

RT

AM

EN

TO

DE

EN

GE

NH

AR

IA C

IVIL



Elevation of vaults (I)



Elevation of vaults (II)



Dismantling (III)….



Protection



Adjusting colors



Completed South wall

Befo

re

Aft

er



Stainless steel AISI 316L



Drilling



2nd Level



1st Level



Floor Level

2nd Level

1st Level



Information

management

system



Why?

Large amount of information generated by the different specialists,

which is generally not handled adequately by owners and/or

authorities.

Valuable information is lost in a complex process of reaching a

decision and information tends to get forgotten or misplaced in the

course of time.

Objective 1: Develop an application for the efficient management

and visualization of the information for interventions of cultural

heritage buildings.

Objective 2: Promote “technical and scientific” culture and

dissemination



Virtual reconstruction (I)

“Ideal plan” of Clairvaux,

France

Medieval parts of the

monastery



Virtual reconstruction (II)

Reference model for church General view



Virtual reconstruction (III) E

xte

rna

l vie

ws

Inte

rna

l vie

ws



Web-based application (I)

Spatial units

Database is browsed through: (a) menus; (b) photographs, 3D models,

panoramic views; (c) hotspots.

Themes



Web-based application (II)

Panoramic views



Web-based application (III)

Database is searched with pdf, doc, dwg and other files



Monastery of Jerónimos in Lisbon



The crown asset of

Portuguese heritage

buildings

Construction from 1499

Built with limestone

Considerable dimensions

in plan, more than 300

50 m2, and an average

height of 20 m (50 m in

the towers)

Evolves around two

courts. The larger court

is bordered by a long

arcade of two levels that

hosts the Ethnographic

Museum of Archaeology

and the Maritime

Museum. The smaller

court or the Cloister is

bordered by the Church,

the Sacristy, the Chapter

Room, the Refectory

Description



Gathered data

Local Seismicity



7

6

Views

3 4 6

5

5

1

2

Cross

-section

Church



Tiles removal for visual inspection

Wallets for supporting tiles (20th century)

Radar inspection

Ribs visual inspection

In situ investigation



Plan of the nave

Nave cross-sections

Longitudinal cross-section

Transept cross-section

In situ geometrical survey



Tilting of the columns and GPR of the columns



Modal Identification of the church – Mode I



Measure deformations and temperature variations of two columns

in the main nave

The system is focused on the columns structural observation,

because they are the best measure of the nave structural behavior

TS4

TS3

TS2

TS1

D

TS6

TS5

C2

C1

TS4 Instituto Português do

Património Arquitectónico

Direcção Regional de Lisboa

Escalas: 1/200 Data: Julho 2004

Processo: 04-DEC/E-?

Desenhou:

Requerente:

Ficheiro: Plano_Monitorizacao.dwg

Departamento de Engenharia Civil

Campus de Azurém

4800-058 Guimarães

Verificou:

Descrição: Desenho:

Nº03

- Todas as cotas devem ser confirmadas no local

Notas:

Igreja do Mosteiro dos Jerónimos

Plano de Monitorização

(Cortes)

Legenda:

Cablagem

SENSORES:

Clinómetro (número)

Temperatura na superfície (número)

Sistema de aquisição e armazenamento

de dados

Cn

TSn

D

TS1TS3

C2 C1

TS4 TS2

Static Monitoring System (I)



North Tiltmeter vs Temperature

-0.3

-0.2

-0.1

0.0

0.1

0.2

0.3

5.0

10

.0

15

.0

20

.0

25

.0

30

.0

35

.0

Temperature [ºC]

Rota

tion

[m

m/m

]

North Tiltmeter

(Daily Moving Average)

-0.3

-0.2

-0.1

0.0

0.1

0.2

0.3

Sep

-05

Oct

-05

No

v-0

5

Dec

-05

Jan-0

6

Feb

-06

Mar

-06

Ap

r-0

6

May

-06

Jun

-06

Jul-

06

Au

g-0

6

Sep

-06

Oct

-06

No

v-0

6

Dec

-06

Jan-0

7

Feb

-07

Mar

-07

Ap

r-0

7

May

-07

Jun

-07

Date

Rota

tion

[m

m/m

]

5

10

15

20

25

30

35

Tem

per

ature

[ºC

]

North Tiltmeter

Temperature

Static Monitoring System (II)



Accelerations measurements in two points: in the base and in the

main nave. Dynamic monitoring system separated from static one.

Dynamic Monitoring System (I)

Monitored since February 2006

Trigger armed for low-level signals corresponding to micro-tremors on site

One 10-minute record per month

Seasonally (for 24 hours), one 10-minute record per hour



1st Frequency versus Temperature

3.5

3.6

3.7

3.8

3.9

4.0

4.1

4.2

5 10 15 20 25 30 35Temperature [ºC]

Fre

qu

ency

[H

z]

EstimatedModel98% CISeries4

Confidence Intevals

3.5

3.6

3.7

3.8

3.9

4.0

4.1

4.2

Feb

-05

Ap

r-0

5

Jun

-05

Au

g-0

5

Oct

-05

Dec

-05

Feb

-06

Ap

r-0

6

Jun

-06

Au

g-0

6

Oct

-06

Dec

-06

Feb

-07

Ap

r-0

7

Date

Fre

qu

ency

[H

z]

EstimatedModel98% CIUpper CI

Dynamic Monitoring System (II)



Dynamic Monitoring System (II)

Small shake (M=5.8, MMI = V in Lisbon) felt. No damage recorded



8

6 Full model with 135.000 dof

Modal superposition

Non-linear with equivalent

static loading

Load-displacement diagram

Nó 21747 Torre

0.43

0.87

1.34

2.48

3.48

4.71

11.36

25.49

22.60

16.11

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

1.1

1.2

1.3

0.00 5.00 10.00 15.00 20.00 25.00 30.00

Deslocamento z (cm)

Fa

cto

r d

e C

arg

a

Deformed mesh

Details

Full Building Analysis



8

7

0.0

0.5

1.0

1.5

2.0

2.5

0.00 0.10 0.20 0.30

Vertical displacement (m)

Lo

ad F

acto

r

Column

Vault key

Load displacement diagram

Incremental deformed mesh

Non-linear Analysis:

Loading = Self-weight

ft = 0

fc, masonry = 6 N/mm2

fc, infill = 1 N/mm2

Nave Analysis



8

8

Load-displacement diagram Incremental deformed mesh

Max.

principal

strains

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

0 0.05 0.1 0.15 0.2 0.25 0.3

Vertical displacement (m)

Load F

acto

r

Min.

principal

stresses

Transept Analysis



8

9

3D beam element model

Calibration of the model – Dynamic identification

Model for Dynamic Analysis



Vertical loading

North façade South façade

Collapse Mechanisms



9

1

Possible Strengthening Measures

1: Pre-stress the columns

2: Load transfer

3: Increase column strength



Conclusions

Conservation Engineering is a new, complex and exciting

field. Engineers (and architects) are still educated today

much in the same way as they were educated decades ago

= New construction

Few differences exists between conservation engineering

for buildings with and without cultural value

Specific tools and knowledge for the discipline are available

A scientific methodology with a sound basis is available, but

experience and personal judgment remain a key issue

Case studies have been presented, stressing the need to:

(a) clearly understand the behavior of complex structures;

(b) adequately assess the need of structural strengthening;

(c) analyze the cost of different possible solutions at an

early design phase



Examples of

analysis and

interventions :

Case studies on

monuments

Paulo B. Lourenço

[email protected]

www.civil.uminho.pt/masonry

Documents

לארשיב תשרומ ירתא Examples of analysis and interventions ... studies on... · Deterioração das pedras do arco Fendas na separação dos panos de alvenaria Fendas