dcee4 paper 9

The 4th International Workshop on

Design in Civil and Environmental Engineering

Taipei, Taiwan October 30-31, 2015

Design for robustness, resilience and anti-fragility

in the built and urban environment: considerations

from a civil engineering point of view.

K. Gkoumas

StroNGER srl, Italy

F. Petrini

Sapienza University of Rome, Italy

F. Bontempi


Design for robustness, resilience and anti-fragility in the built and urban environment: considerations from a civil engineering point of view.

Konstantinos Gkoumas, PhD, PE

References: CALVINO, I. INVISIBLE CITIES. PAPERBACK, 165 PAGES PUBLISHED 1974 BY HARCOURT

BRACE & COMPANY.

Cities in Calvino’s book represent complex

historical examples and imaginary

possibilities, characterized by their infinite

complexity, their intensive urban landscape,

and their strong interactions between them

and their inhabitants. While some of them

are utopian models of success, the majority

of them are left to their destiny, being

responsive to their purpose and to the acts of

their inhabitants.

What emerges is the idea that some cities are

“invisible”, ever-changing, with details

ready to be discovered (or left behind): in

this sense, people continue to live in the

cities, albeit the deficiencies or crisis

situations.

urban complexity – is there a choice?



word cloud



antrifragility, resilience and robustness – a development timeline

resilience

robustness

antifragility

timespacial complexity

spatialcomplexity

Ronan Point (1968)Building (5th Amendment) Regulations 1970

1960 1970 1980 1990 2000 2010

Seismic (Bruneau et al. 2003)Urban (MCEER, 2006)Ecological (Holling, 1973)

(TALEB, 2012)

Eurocodes (‘80s)

structural (global)+resilience (local)

+resilience (social)

+antifragility (social)

robustness: single structure (or a

series of structures)

antifragility and resilience

complex of structures in the most

wide sense, including issues well

beyond structural design.

• scale (small - big)

• context (structural – urban - social)

• multi-, trans- and inter - disciplinarity



black swan

vulnerability

cause

damage

index

robustness

collapse

resistance

progressive

collapse

Photo Credit: Wikipedia Commons.

member

consequence

factor

• introduction

• structural robustness

• intro

• assessment methods

• member-based design

• robustness assessment of a truss bridge

(summary)

• disaster resilience

• intro

• definition

• a framework based on multiscale philosophy,

discrete events and continuous deterioration

• resilience assessment of a water infrastructure

(summary)

• antifragility (outline)

• conclusions and considerations



a starting point: Ronan Point Tower Block – May 16, 1968

Description:- apartments building;

- built between 1966 and 1968;

- 64 m tall, 22 story;

- walls, floors, and staircases was precast

concrete;

- each floor was supported directly by the walls

in the lower stories, (bearing walls system).

The event:- May 16, 1968 a gas explosion blew out an

outer panel of the 18th floor,

- the loss of the bearing wall causes the

progressive collapse of the upper floors,

- the impact of the upper floors’ debris caused

the progressive collapse of the lower floors.

Cause Damage Pr. Collapse



qualitative definitions of structural robustness

[EN 1991-1-7: 2006 ]: ability of a structure to withstand actions due

to fires, explosions, impacts or consequences

of human errors, without suffering damages

disproportionate to the triggering causes

[SEI 2007,

Beton Kalender 2008]: insensitivity of the structure to local failure

structure B

d

P

s

STRUCTURE B:

P

s

ROBUSTNESS CURVES

P (performance)

structure A

STRUCTURE A

damaged

integer

DP

damaged

more performant, less resistant

integer

(damage level)

DPDP

more performant, less robust less performant, more robust

structural robustness

A B



RISK-BASED[Faber, 2005]

R

Iinddir

dirrob

R

R

direct risk

indirect riskDAMAGE-BASED

n

1i'

i

i

)K(tr

)K(tr.Deg.Stiff

ithelement stiffness matrix

(integer state)damagedelements

ithelement stiffnessmatrix (damaged state)

[Yan&Chang, 2006] [Biondini &Frangopol, 2008]

1

0

energy between intact

and damaged system

(backward pseudo-loads)

energy between intact

and damaged system

(forward pseudo-loads)

Indirect

Risk

Direct

Risk

Indirect

Risk

Direct

Risk

Reference:

Olmati, P., Brando, F., Gkoumas, K. “Robustness assessment of a Steel Truss Bridge”, ASCE/SEI Structures Congress,

Pittsburgh, Pennsylvania, May 2-4, 2013.

B

A Withstand actions, events

Withstand damages

structural robustness assessment

TOPOLOGY-BASEDOther:



𝑅𝑑𝑢𝑛𝑑𝑎𝑚𝑎𝑔𝑒𝑑

− 𝐸𝑑𝑢𝑛𝑑𝑎𝑚𝑎𝑔𝑒𝑑

≥ 0member-based design

𝑅 − 𝐸 ≥ 0limit state design

Resistance (probabilistic) Solicitation (probabilistic)

Resistance (design values) Solicitation (design values)

(1 − 𝐶𝑓𝑆𝑐𝑒𝑛𝑎𝑟𝑖𝑜)𝑅𝑑

𝑢𝑛𝑑𝑎𝑚𝑎𝑔𝑒𝑑−𝐸𝑑

𝑢𝑛𝑑𝑎𝑚𝑎𝑔𝑒𝑑≥ 0

Member consequence factor based design

0 ≤ 𝐶𝑓 ≤ 1

• Cf quantifies the influence that a loss of a structural element has on the load carrying capacity.

• Cf provides to the single structural member an additional load carrying capacity, in function of the

nominal design (not extreme) loads that can be used for contrasting unexpected and extreme loads.

• Essentially, if Cf tends to 1, the member is more likely to be important to the structural system;

instead if Cf tends to 0, the member is more likely to be unimportant to the structural system.

member consequence factor and robustness assessment

0EγγRγγ kEMEk

1

Rd

1

MR

0E)R(*)C1( kEdMEk

1

Rd

1

MRf



• 𝐶𝑓𝑆𝑐𝑒𝑛𝑎𝑟𝑖𝑜is evaluated by the maximum percentage difference of the structural stiffness

matrix eigenvalues of the damaged and undamaged configurations of the structure.

𝐶𝑓𝑆𝑐𝑒𝑛𝑎𝑟𝑖𝑜 = 𝑚𝑎𝑥

𝜆𝑖𝑢𝑛 − 𝜆𝑖

𝑑𝑎𝑚

𝜆𝑖𝑢𝑛 100

𝑖=1−𝑁

where, 𝜆𝑖𝑢𝑛and 𝜆𝑖

𝑑𝑎𝑚are respectively the i-th eigenvalue of the structural stiffness

matrix in the undamaged and damaged configuration, and N is the total number of the

eigenvalues.

• the corresponding robustness index (𝑅𝑆𝑐𝑒𝑛𝑎𝑟𝑖𝑜) is therefore defined as:

𝑅𝑆𝑐𝑒𝑛𝑎𝑟𝑖𝑜=1 - 𝐶𝑓𝑆𝑐𝑒𝑛𝑎𝑟𝑖𝑜

• low values of Cf do not necessarily mean that the structure survives after the failure of

the structural member: this is something that must be established by additional

analysis that considers the loss of the specific structural member.

member consequence factor and robustness assessment



case study summary: I-35 West Bridge, Minneapolis, MN

http://www.dot.state.mn.us/i35wbridge/ntsb/finalreport.pdf

d1d2d3

d4

d5d7

37

59

42 4535 38

23

63

41

58 5565 62

77

0

20

40

60

80

100

1 2 3 4 5 6 7R

ob

ust

nes

s %

ScenarioCf max Robustness

37

59

42 4535 38

23

63

41

58 5565 62

77

0

20

40

60

80

100

1 2 3 4 5 6 7

Ro

bu

stn

ess

%


83 87 88

5360

86

64

17 13 12

4740

14

36

0

20

40

60

80

100

1 2 3 4 5 6 7R

obust

nes

s %


Damage scenario Damage scenariod1 d2 d3 d4 d5 d6 d7 d1 d2 d3 d4 d5 d6 d7

Olmati, P., Gkoumas, K., Brando, F. and Cao, L. (2013) Consequence-

based robustness assessment of a steel truss bridge. Steel and Composite

Structures - An International Journal, Vol. 14, No. 4, pp. 379-395.

http://www.dot.state.mn.us/i35wbridge/ntsb/finalreport.pdf



black swan

vulnerability

cause

damage

index

robustness

collapse

resistance

progressive

collapse


member

consequence

factor

• introduction


• intro




(summary)


• intro

• definition




(summary)





(disaster/urban/community) resilience

definition (not univocal):

a resilient community is defined as the one that has the ability to absorb disaster

impacts and rapidly return to normal socioeconomic activity.

MCEER (Multidisciplinary Center for Earthquake Engineering Research), (2006). “MCEER’s Resilience Framework”. Available at

http://mceer.buffalo.edu/research/resilience/Resilience_10-24-06.pdf

NEHRP (National Earthquake Hazards Reduction Program), 2010. “Comments on the Meaning of Resilience”. NEHRP Technical

report. Available at http://www.nehrp.gov/pdf/ACEHRCommentsJan2010.pdf

MCEER framework for resilience evaluation:

Initial losses recovery time, depending on:

• resourcefulness

• rapidity

Disaster strikes

Systemic

Robustness



MCEER (Multidisciplinary Center for Earthquake Engineering Research), (2006). “MCEER’s Resilience Framework”. Available at

http://mceer.buffalo.edu/research/resilience/Resilience_10-24-06.pdf

resilience is inversely proportional to the area A.

(dQ/dt)L0

TR

(dQ/dt)0

A

(disaster/urban/community) resilience

definition (not univocal):

a resilient community is defined as the one that has the ability to absorb disaster

impacts and rapidly return to normal socioeconomic activity.

NEHRP (National Earthquake Hazards Reduction Program), 2010. “Comments on the Meaning of Resilience”. NEHRP Technical

report. Available at http://www.nehrp.gov/pdf/ACEHRCommentsJan2010.pdf

MCEER framework for resilience evaluation:



MCEER (Multidisciplinary Center for Earthquake EngineeringResearch), (2006). “MCEER’s Resilience Framework”.

-- = ordinary node

= critical node in case of emergency---

= principal link (e.g. road)

HOSPITAL

HOUSE AGGRGATE

MALL

SHOPPING CENTEROFFICE

HOUSE AGGRGATE

FIRE DEPARTMENT

NUCLEAR PLANT

HOSPITAL

HOUSE AGGRGATE

MALL

SHOPPING CENTEROFFICE

HOUSE AGGRGATE

FIRE DEPARTMENT

NUCLEARPLANT

= earthquake action

= blast action= fire action

representation of an urban development or a large infrastructure as a network of nodes and links

nodes: relevant premises of the infrastructure links: local and access roads, pipelines and supply system

Initial losses

Recovery time:

• Resourcefulness• Rapidity

Disaster strikes

A

L0

(dQ/dt)0

LOCAL- LEVEL:Contribute of the single premise (e.g. hospital, by considering the interrelations with proximity elements)

NETWORK- LEVEL:- Convolution of the local-level contributes

dLi

quantitative definition of Resilience (MCEER) multiscale philosophy

disaster strikes --> hazard scenario

proposed framework



Load

Network Model for

resilience

Multi-hazard

Scenarios

Local Level

NetworkLevel

Local resilience indicators Network resilience indicators

ASS

ESSM

ENT

an

d M

ITIG

ATIO

N

(An

aly

sis

for

each

no

de

an

d li

nk)

Scenario output before mitigation

Scenario output after mitigation

ResISt

framework for resilience assessment

Structure performanceA

B Recovery

E.g. Repair time

Damage

Action

Damage/Disservice

% of rescued

Action values

IM

A

IM

100 %

People safetyB

Quality

Indicator

Status of nodes and links

(no interaction)A

Quality

Indicator

Interactions effects (quality drop)B

L0i TR

i

Quality (network level)

Combination of local indicators

Indicator

L0 TR

Resilience ∞ 1 /A

C

Local resilience indicators are evaluated for

each node and Link and for each scenarioNetwork resilience indicators are evaluated for

each scenario

---- = Output

---- = comment

Qu

alit

y

L0 = initial losses

TR = recovery time

Infrastructure

representation

Hazard

Analysis

Protection

analysis

Performance

analysis

Resilience Assessment

Network Level

1

2 System Recovery functionD

** Picture taken from:

Decò A., Bocchini P., Frangopol D.M.. A probabilistic approach for the prediction of seismic resilience of bridges.

Earthquake Engineering and Structural Dynamics, Wiley, DOI: 10.1002/eqe.2282

Recovery

analysis

**

3




combined effect of discrete events and continuous deterioration

( )

(s s )

s ss

R ( s )

s s ( )

C

C

s




-

Aftermath of the event

- s

i. historical - political - decisions (e.g. local governance) influence the initial system quality

Q0. This parameter is related to the initial system state.



-


- s

ii. urban and social service planning is relevant for the pre-event system integrity and it is one

of the factors determining the trend of system quality before the event (dQ/dt) and the

amount of immediate losses (ΔQ). The first parameter is by a statistical correlation

between the political decision and the quality trend, while the second parameter can be

modeled by the system fragility.




-


- s

iii. fast decisions are taken during the event or a disaster (on the basis of knowledge and

experience from similar past events - if any - and the system properness knowledge); the

decisions in this phase influence the initial slope of the recovery phase (dQR/dt), a

parameter that can be modeled by a statistical correlation between the political decision

and the quality trend.




-


- s

iv. emergency plans and prioritization of recovery actions are relevant in the aftermath of the

event (recovery phase). In addition, the declaration of a state of emergency can have a

substantial short and long-term effect on the local economy. The actions in this phase

influence the shape of the recovery function fR(t).




-


- s

v. urban and social service re-planning on the basis of the consequences of the occurred event

are relevant in the long run (influencing the losses and the recovery for the next discrete

event).




WU

WDHY

CBCR

CU

RETAINING WALL UP (WU) RETAINING WALL DOWN (WD) HYDROELECTRIC POWER STATION (HY)

CONDUIT UP (CU) CONDUIT ROSALBA

CONDUIT PAVONCELLI BIS

1

2

34

5

6

7

1 2 3

4 5 6

7

HYDRAULIC JUNCTION

ELECTRICITY

WATER

Infrastructure plan view Individuation of the system/network components Representation of the system

Outputs

Load

Network Model for

resilience

Multi-hazard

Scenarios

Local Level

NetworkLevel


ASS

ESS

ME

NT

an

d M

ITIG

AT

ION

(A

na

lysi

s fo

r e

ach

no

de

an

d li

nk)



ResISt



B Recovery

E.g. Repair time

Damage

Action

Damage/Disservice

% of rescued

Action values

IM

A

IM

100 %

People safetyB

Quality

Indicator


(no interaction)A

Quality

Indicator


L0i TR

i



Indicator

L0 TR

Resilience ∞ 1 /A

C



each scenario

---- = Output

---- = comment

Quality

L0 = initial losses

TR = recovery time

Infrastructure

representation

Hazard

Analysis

Protection

analysis

Performance

analysis


Network Level

1





Recovery

analysis

**

3

RISE

framework for resilience assessmentLoad

Network Model for

resilience

Multi-hazard

Scenarios

Local Level

NetworkLevel


ASS

ESS

ME

NT

an

d M

ITIG

AT

ION

(A

na

lysi

s fo

r e

ach

no

de

an

d li

nk)



ResISt



B Recovery

E.g. Repair time

Damage

Action

Damage/Disservice

% of rescued

Action values

IM

A

IM

100 %

People safetyB

Quality

Indicator


(no interaction)A

Quality

Indicator


L0i TR

i



Indicator

L0 TR

Resilience ∞ 1 /A

C



each scenario

---- = Output

---- = comment

Qu

ality

L0 = initial losses

TR = recovery time

Infrastructure

representation

Hazard

Analysis

Protection

analysis

Performance

analysis


Network Level

1





Recovery

analysis

**

3

RISE


case study summary: energy and water supply infrastructure

Ortenzi, M., Petrini, F., Bontempi,

F. and Giuliani, L. (2013) RISE : a

method for the design of resilient

infrastructures and structures

against emergencies. Proceedings of

the 11th International Conference

on Structural Safety & Reliability.

New York, USA, June 16-20.



black swan

vulnerability

cause

damage

index

robustness

collapse

resistance

progressive

collapse


member

consequence

factor

• introduction


• intro




(summary)


• intro

• definition




(summary)





References: Taleb, Nassim Nicholas (November 2012). Antifragile: Things That Gain from Disorder(1st ed.). London:

Penguin. p. 519. ISBN 1-400-06782-0 (Photo: The art of manliness).

-----

----

“anti-fragility”

Things that are fragile

break or suffer from

chaos and randomness.

The resilient, or

robust, don’t care if

circumstances become

volatile or disruptive

(up to a point).

Things that are anti-

fragile grow and

strengthen from

volatility and stress (to

a point).



conclusions and considerations

• purpose of this study is to review recent developments, together

with corroborated research, focusing on new trends in the

robustness, resilience-based, and antifragile design.

• methods for the robustness and resilience assessment are proposed.

• antifragile design has the potential to become a major topic in the

imminent future, as has been the case for resilience-based design.

• since the recent introduction of the term by Taleb, there are few or

none references in literature (especially concerning urban design or

civil and architectural engineering in general).

• a challenge remains on how to quantify antifragility.

The 4th International Workshop on

Design in Civil and Environmental Engineering

Taipei, Taiwan October 30-31, 2015

Design for robustness,

resilience and anti-fragility

in the built and urban

environment: considerations

from a civil engineering

point of view.

K. Gkoumas

StroNGER srl, Italy

F. Petrini


F. Bontempi
