ph.d. thesis project of paolo e. sebastiani pbee - mala rijeka viaduct

41
1 P. E. Sebastiani Ph.D. Student Sapienza University of Rome - a.a. 2013/2014 [email protected] [email protected] [email protected] www.francobontempi.org 1. PERFORMANCE-BASED EARTHQUAKE ENGINEERING CONDITIONAL PROBABILISTIC APPROACH (IM-BASED METHODS) APPROACHES UNCONDITIONAL PROBABILISTIC APPROACH SEMI-PROBABILISTIC APPROACH (DM2008) PHILOSOPHY PBEE DETERMINISTIC APPROACH EVALUATION, DESIGN AND CONSTRUCTION OF STRUCTURES TO MEET SEISMIC PERFORMANCE OBJECTIVES 1.1 PBEE Outline

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The case study bridge "Mala Rijeka" is one of the most important bridges on the Belgrade - Bar International Line. The bridge was built in 1973 as the highest railway bridge in the World (Worlds Record Lists) and it is a continuous fivespan steel frame carried by six piers of which the middle ones have heights ranging from 50 to 137.5 m measured from the foundation interface. The main steel truss bridge structure consists in a continuous girder with a total length L=498.80 m. Static truss height is 12.50 m, and the main beams are not parallel, but are radially spread, in order to adjust to the route line. Performance-based earthquake engineering (PBEE) consists of the evaluation, design and construction of structures to meet seismic performance objectives (expressed in terms of repair costs, downtime, and casualties) that are specified by stakeholders (owners, society, etc.). It is based on the premise that performance can be predicted and evaluated with quantifiable confidence to make, together with the client, intelligent and informed trade-offs based on life-cycle considerations rather than construction costs alone.

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Page 1: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

1

P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

[email protected]

[email protected]

www.francobontempi.org

1. PERFORMANCE-BASED EARTHQUAKE ENGINEERING

CONDITIONAL PROBABILISTIC APPROACH

(IM-BASED METHODS)

APPROACHES

UNCONDITIONAL PROBABILISTIC

APPROACH

SEMI-PROBABILISTIC APPROACH (DM2008)

PHILOSOPHY

PBEE DETERMINISTIC APPROACH

EVALUATION, DESIGN AND

CONSTRUCTION OF STRUCTURES TO

MEET SEISMIC PERFORMANCE

OBJECTIVES

1.1 – PBEE Outline

Page 2: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

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1.2 – Definition

Performance-based earthquake engineering (PBEE) consists of the evaluation,

design and construction of structures to meet seismic performance objectives

(expressed in terms of repair costs, downtime, and casualties) that are specified

by stakeholders (owners, society, etc.)

It is based on the premise that performance can be predicted and

evaluated with quantifiable confidence to make, together with the client,

intelligent and informed trade-offs based on life-cycle considerations rather than

construction costs alone.

Krawinkler, H. and Miranda, E. (2004). “Performance-Based Earthquake Engineering”. Chapter 9 of

Earthquake Engineering: From engineering seismology to performance-based engineering, edited by Y.

Bozorgnia, and V. Bertero, CRC press.

1. PERFORMANCE-BASED EARTHQUAKE ENGINEERING

1.3 – Assumptions

P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

[email protected]

[email protected]

www.francobontempi.org

Page 3: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

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1.4 – Development of PBEE

Most of the concepts that are implemented in the context of PBEE are not new.

In various forms they have been explored, tried and partially

implemented in past design/evaluation guidelines and standards of

various countries and industries

In the United States various efforts were initiated during the early 1990s which

faced up to the many challenges of performance-based seismic design. The most

widely known ones are Vision 2000 (SEAOC, 1995), FEMA 273 and FEMA 274

(1996) and ATC-40 (1996)

1. PERFORMANCE-BASED EARTHQUAKE ENGINEERING

Krawinkler, H. and Miranda, E. (2004). “Performance-Based Earthquake Engineering”. Chapter 9 of

Earthquake Engineering: From engineering seismology to performance-based engineering, edited by Y.

Bozorgnia, and V. Bertero, CRC press.

1.5 – PBEE concepts in the Codes

P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

[email protected]

[email protected]

www.francobontempi.org

Page 4: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

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1.6 – Vision 2000 report (SEAOC 1995)

1. PERFORMANCE-BASED EARTHQUAKE ENGINEERING

One of the many strong points of the Vision 2000 document is that it proposes

a comprehensive design/assessment/build process that incorporates important

aspects of:

• Selection of a suitable site

• Selection of suitable structural materials and systems

• Configuration and continuity of load path

• Quality of detailing

• Strength and stiffness

• Consideration of nonstructural and content systems

• Quality and consistency of design

• Quality of design review

• Quality of construction

• Quality of inspection

P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

[email protected]

[email protected]

www.francobontempi.org

Page 5: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

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1. PERFORMANCE-BASED EARTHQUAKE ENGINEERING

Performance objectives for buildings, recommended in SEAOC (1995).

P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

[email protected]

[email protected]

www.francobontempi.org

Page 6: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

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1. PERFORMANCE-BASED EARTHQUAKE ENGINEERING

CONDITIONAL

PROBABILISTIC

APPROACHES

PEER

METHOD

It is not in closed form but it allows more flexibility and generality in the evaluation of the desired so-called “decision variable”, not necessarily coinciding with Pf.

SAC/FEMA

It has the advantage of providing a closed-form expression for the failure probability (Pf), that can also be put in a partial factor format.

1.7 – Conditional Probabilistic Approaches

In the middle of the 90’s very promising results started to materialize (i.e.

Bazzurro and Cornell 1994, Cornell 1996). The problem was posed in terms of

a direct (probabilistic) comparison between demand and capacity, with the

demand being the maximum of the dynamic response of the system to a seismic

action characterized in terms of a chosen return period

Fib (2012) Probabilistic performance-based seismic design. Bulletin n°68, Fédération internationale du

béton, Lausanne, Switzerland

P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

[email protected]

[email protected]

www.francobontempi.org

Page 7: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

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2. PEER METHOD: A PROBABILISTIC

DESIGN/ASSESSMENT APPROACH TO PBEE

2.1 – Definition

The Pacific Earthquake Engineering Research (PEER) Center has focused for

several years on the development of procedures, knowledge and tools for

a comprehensive seismic performance assessment of buildings and

bridges

In the approach, decision variables are identified whose quantification, together

with an assessment of important uncertainties, will make it feasible to

characterize and manage economic and societal risks associated with

direct losses, downtime and collapse and life safety.

Krawinkler, H. and Miranda, E. (2004). “Performance-Based Earthquake Engineering”. Chapter 9 of

Earthquake Engineering: From engineering seismology to performance-based engineering, edited by Y.

Bozorgnia, and V. Bertero, CRC press.

P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

[email protected]

[email protected]

www.francobontempi.org

Page 8: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

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2.2 – Components of PEER method: Performance Targets

2. PEER METHOD: A PROBABILISTIC

DESIGN/ASSESSMENT APPROACH TO PBEE

It is assumed that a performance target can be expressed in terms of a

quantifiable entity and, for instance, its annual probability of exceedance. For instance, l$(y), the mean annual frequency (MAF) of the loss

exceeding y dollars, could be the basis for a performance target

P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

[email protected]

[email protected]

www.francobontempi.org

Page 9: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

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2.3 – Components of PEER method: Decision Variables

2. PEER METHOD: A PROBABILISTIC

DESIGN/ASSESSMENT APPROACH TO PBEE

The quantifiable entities, on which performance assessment is based, are

referred to as decision variables (DVs). Examples of DVs of primary interest are

the existence of collapse, the number of casualties, dollar losses and the length

of downtime

P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

[email protected]

[email protected]

www.francobontempi.org

Page 10: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

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2. PEER METHOD: A PROBABILISTIC

DESIGN/ASSESSMENT APPROACH TO PBEE

To compute DVs and their uncertainties, other variables have to be evaluated to

define:

1. The seismic hazard

2. The demands imposed on the structural systems by the hazard

3. The state of damage

P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

[email protected]

[email protected]

www.francobontempi.org

Page 11: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

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2.4 – Components of PEER method: Seismic Hazard

2. PEER METHOD: A PROBABILISTIC

DESIGN/ASSESSMENT APPROACH TO PBEE

The seismic hazard is quantified in terms of a vector of intensity measures (IMs),

which should define the seismic input to the structure. This vector could have a

single component, such as spectral acceleration at the first mode period of the

structure, Sa(T1), or could have several. If a single component is used, such as

Sa(T1), the hazard is usually defined in terms of a hazard curve. The outcome of

hazard analysis, which forms the input to demand evaluation, is usually expressed in terms of an MAF of IMs, i.e., l(IM),

P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

[email protected]

[email protected]

www.francobontempi.org

Page 12: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

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2.5 – Components of PEER method: Engineering Demands Parameters

2. PEER METHOD: A PROBABILISTIC

DESIGN/ASSESSMENT APPROACH TO PBEE

Given the ground motion hazard, a vector of engineering demand parameters

(EDPs) needs to be evaluated, which defines the response of the structure in

terms of parameters that can be related to DVs. Interstory drift is an example

of a relevant EDP for buildings

P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

[email protected]

[email protected]

www.francobontempi.org

Page 13: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

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2.6 – Components of PEER method: Damage Measures DM

2. PEER METHOD: A PROBABILISTIC

DESIGN/ASSESSMENT APPROACH TO PBEE

In most cases an intermittent variable, called a damage measure (DM), has to be

inserted between the EDP and the DV simply to facilitate the computation of

DVs from EDPs. A DM describes the damage and consequences of damage to a

structure or to a component of the structural, nonstructural or content system,

and the term G (DM|EDP) can be viewed as a fragility function for a specific

damage (failure) state (probability of being in or exceeding a specific damage

state, given a value of EDP).

P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

[email protected]

[email protected]

www.francobontempi.org

Page 14: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

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2. PEER METHOD: A PROBABILISTIC

DESIGN/ASSESSMENT APPROACH TO PBEE

The assessment problem has been “de-constructed” into the four basic

elements of

1. hazard analysis

2. demand prediction

3. modeling of damage states

4. failure or loss estimation

by introducing the three intermediate variables, IM, EDP and DM

To close the loop…

1. EDPs have to be related to IMs (Probabilistic Seismic Demand Analysis

PSDA)

2. DMs have to be related to EDPs (Damage Analysis)

P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

[email protected]

[email protected]

www.francobontempi.org

Page 15: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

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2. PEER METHOD: A PROBABILISTIC

DESIGN/ASSESSMENT APPROACH TO PBEE

Relationships between EDPs and IMs (also called Probabilistic Seismic Demand

Models PSDM) can be obtained through simulations, which should incorporate

the complete structural, geotechnical and SFSI (soil–foundation–structure

interaction) systems

2.7 – Probabilistic Seismic Demand Analysis in the PEER method

So the first step is the evaluation of a PSDM

The outcome of this process, which may be referred to PSDA, can be

expressed as G(EDP|IM) or more specifically as G[EDP ≥ y | IM = x], which is the

probability that the EDP exceeds a specified value y, given (i.e., conditional) that

the IM is equal to a particular value x

P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

[email protected]

[email protected]

www.francobontempi.org

Page 16: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

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2. PEER METHOD: A PROBABILISTIC

DESIGN/ASSESSMENT APPROACH TO PBEE

Synthetic or recorded accelerograms

SEISMIC LOADS

STRUCTURE

Geometry Meterials Method of design Ductility Isolation system

INPUTS

Type Range of values Scalar or vector One or more

EDP

IM

SETTINGS

Type Range of values Scalar or vector One or more

COMMON APPROACHES

BIN APPROACH

CLOUD METHOD

STRIPE METHOD

IDA SIMPLIFIED METHOD

IMPROVED CLOUD

METHOD MCS - LHS

EMPIRICAL METHOD

PSDM

2.8 – PSDM in the PSDA

Two values for each level of IM: - mIM , Median of EDP

- z, Standard deviation of EDP

P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

[email protected]

[email protected]

www.francobontempi.org

Page 17: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

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2. PEER METHOD: A PROBABILISTIC

DESIGN/ASSESSMENT APPROACH TO PBEE

A regression analysis can be used to obtain the mean (mIM) and the standard

deviation (z) by assuming the logarithmic correlation between median EDP and

an appropriately selected IM:

where the parameters "a" and "b" are regression coefficients obtained for

example by the nonlinear time history analyses

ln(𝐸𝐷𝑃) = ln 𝑎 + 𝑏 𝑙𝑛(𝐼𝑀)

P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

[email protected]

[email protected]

www.francobontempi.org

Page 18: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

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2. PEER METHOD: A PROBABILISTIC

DESIGN/ASSESSMENT APPROACH TO PBEE

Assuming a log-normal distribution of EDP at a given IM, the probability that the

EDP exceeds a specified value y, given (i.e., conditional) the IM, can be written

as:

where F is the standard normal distribution function

𝐺 𝐸𝐷𝑃 ≥ 𝑦|𝐼𝑀 = 1 − Φ ln 𝑦 − ln(𝑎 𝐼𝑀𝑏)

𝜁

The remaining variability in ln(EDP) at a given IM is assumed to have a constant

variance for all IM range, and the standard deviation can be estimated:

𝜁 = ln 𝐸𝐷𝑃𝑖 − (ln 𝑎 + 𝑏 ln 𝐼𝑀𝑖)

2𝑛𝑖=1

𝑛 − 2

P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

[email protected]

[email protected]

www.francobontempi.org

Page 19: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

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2. PEER METHOD: A PROBABILISTIC

DESIGN/ASSESSMENT APPROACH TO PBEE

2.9 – Damage analysis and fragility functions in the PSDA

The specified value y of EDP, defined previously, can be related to a Damage

Measure DM. Consequently it is possible to define some Limit States LS

according to different damaging.

STRUCTURAL CAPACITY

(DAMAGE ANALYSIS)

P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

[email protected]

[email protected]

www.francobontempi.org

Page 20: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

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2. PEER METHOD: A PROBABILISTIC

DESIGN/ASSESSMENT APPROACH TO PBEE

Nielson, B. G. (2005). “Analytical fragility curves for highway bridges in moderate seismic zones.”

PhD Thesis, Georgia Institute of Technology, Atlanta, Georgia.

P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

[email protected]

[email protected]

www.francobontempi.org

Page 21: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

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2. PEER METHOD: A PROBABILISTIC

DESIGN/ASSESSMENT APPROACH TO PBEE

Therefore G (DM|EDP) can be viewed as a fragility function for three

different damage states

P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

[email protected]

[email protected]

www.francobontempi.org

Page 22: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

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2. PEER METHOD: A PROBABILISTIC

DESIGN/ASSESSMENT APPROACH TO PBEE

2.10 – Loss analysis

The seismic fragility can be convolved with the seismic hazard in order to assess

the annual probability PAi of exceeding the ith damage state:

where H(a) is the hazard curve that quantifies the annual probability of

exceeding a specific level of IM at a site.

Additionally, under the assumption of time-invariant structural resistance, it is

possible to evaluate the T-year probability PTfi of exceeding the damage state ith,

estimated as:

𝑃𝐴𝑖 = 𝑃 𝐷𝐼 ≥ 𝐿𝑆|𝐼𝑀 𝑑𝐻(𝑎)

𝑑𝑎 𝑑𝑎

PTf 𝑖 = 1 − 1 − PA𝑖 T

P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

[email protected]

[email protected]

www.francobontempi.org

Page 23: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

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2. PEER METHOD: A PROBABILISTIC

DESIGN/ASSESSMENT APPROACH TO PBEE

2.10 – Loss analysis

For each damage state it is possible to define a nominal cost of restoration

which depends on the repair strategy. So the probability of exceeding a damage

state can be related to the probability of exceeding a “cost” to close the loop

of PEER method

Fib (2012) Probabilistic performance-based seismic design. Bulletin n°68, Fédération internationale du

béton, Lausanne, Switzerland

P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

[email protected]

[email protected]

www.francobontempi.org

Page 24: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

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2. PEER METHOD: A PROBABILISTIC

DESIGN/ASSESSMENT APPROACH TO PBEE

2.10 – Loss analysis

At the same time it is possible to calculate the expected value of the life-cycle

costs due to seismic damage in present day dollars can be expressed as follow:

where i is the damage state, T=50 years is the remaining service life of the

bridge, Ci is the cost associated with damage state i. An inflation adjusted discount ratio, a=0.03, is used for converting future costs into present values

Wen, Y. K., and Kang, Y. J. (2001a). “Minimum Building Life-Cycle Cost Design Criteria. I:

Methodology.” Journal of Structural Engineering, 127(3), 330–337.

E LCC =1

αT 1 − e−αT −C𝑖

3

𝑖=1

ln 1 − PTf𝑖 − ln 1 − PTf𝑖+1

P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

[email protected]

[email protected]

www.francobontempi.org

Page 25: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

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3. APPLICATION TO THE “MALA RIJEKA” VIADUCT

3.1 – The case study

P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

[email protected]

[email protected]

www.francobontempi.org

Page 26: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

26

3. APPLICATION TO THE “MALA RIJEKA” VIADUCT

P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

[email protected]

[email protected]

www.francobontempi.org

Page 27: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

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3. APPLICATION TO THE “MALA RIJEKA” VIADUCT

3.2 – The case study: geometry

The case study bridge "Mala Rijeka" is one of the most important bridges on

the Belgrade - Bar International Line. The bridge was built in 1973 as the highest

railway bridge in the World (Worlds Record Lists) and it is a continuous five-

span steel frame carried by six piers of which the middle ones have heights

ranging from 50 to 137.5 m measured from the foundation interface. The main

steel truss bridge structure consists in a continuous girder with a total length

L=498.80 m. Static truss height is 12.50 m, and the main beams are not parallel,

but are radially spread, in order to adjust to the route line

P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

[email protected]

[email protected]

www.francobontempi.org

Page 28: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

28

3. APPLICATION TO THE “MALA RIJEKA” VIADUCT

3.3 – Uncertainties

AVAILABLE DATA

•Geometry

•Site Characteristics*

•Damage inspection made in

the 2007

NOT AVAILABLE DATA

•Pier’s section

•Materials

•Devices

Z. Radosavljevid and O, Markovic. (1976) Some Foundation Stability Problems of the Railway Bridge over

the Mala Rijeka. Rock Mechanics 9, 55--64

P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

[email protected]

[email protected]

www.francobontempi.org

Page 29: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

29

3. APPLICATION TO THE “MALA RIJEKA” VIADUCT

3.4 – Modeling of the highest pier

The response of the pier III in figure 1 is evaluated via non-linear dynamic

analyses run in OpenSees 2.2.2 (McKenna, 1997). The column is modelled with a

nonlinear element with fiber-section distributed plasticity

P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

[email protected]

[email protected]

www.francobontempi.org

Page 30: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

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3. APPLICATION TO THE “MALA RIJEKA” VIADUCT

3.5 – Material assumptions

Deck (120 m for the 3th pier) : 870 kNs2/m

Pier (distributed along the pier) : 7166 kNs2/m

3.6 – Mass assumptions

P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

[email protected]

[email protected]

www.francobontempi.org

Page 31: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

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3. APPLICATION TO THE “MALA RIJEKA” VIADUCT

3.7 – Section assumptions

•Tube 6.5 16.5 m x 6.516.5 m

(variable)

•0.5 m of thickness

•Rebar F26 / 0.2 m

SECTION A

P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

[email protected]

[email protected]

www.francobontempi.org

Page 32: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

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3. APPLICATION TO THE “MALA RIJEKA” VIADUCT

3.8 – Pushover analysis to define limit states

First Cracking

st = 5.2 N/mm2 is the concrete tensile strength

SEC 107

SEC 105

SEC 103

SEC 101 P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

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[email protected]

www.francobontempi.org 32

Page 33: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

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3. APPLICATION TO THE “MALA RIJEKA” VIADUCT

3.9 – Pushover analysis to define limit states

SEC 107

SEC 105

SEC 103

SEC 101

Yielding

ss = 440 N/mm2 is the steel yield strength

P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

[email protected]

[email protected]

www.francobontempi.org 33

Page 34: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

3. APPLICATION TO THE “MALA RIJEKA” VIADUCT

3.10 – Pushover analysis to define limit states

Three damage states DS namely slight, moderate and complete damage are

adopted in this study and their concerning limit values are shown in tab. 6.

Through the pushover analysis presented previously, the slight damage has been

associated to the achievement of maximum tensile strength of concrete, while

the moderate one to the yielding of the steel rebar.

A comparison between the values adopted by Choi et al. (2004) and the

ductility factor defined in the EC8 for piers, has allowed us to define also limit

values referred to the collapse.

P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

[email protected]

[email protected]

www.francobontempi.org 34

Page 35: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

3. APPLICATION TO THE “MALA RIJEKA” VIADUCT

3.11 – PSDM results with different type of retrofit

NOT ISOLATED ISOLATED (FRICTION-PEDULUM SYSTEM) ISOLATED (ELASTOMERIC BEARINGS)

Using the curvature ductility at the pier base mc and displacement ductility dc as

EDPs, for different type of IMs and type of retrofit, the PDSM results are the

following:

Sebastiani P.E., Padgett J.E., Petrini F., Bontempi F. (2014). Effectiveness Evaluation of Seismic

Protection Devices for Bridges in the PBEE Framework. In proceeding of: ASCE-ICVRAM-ISUMA

2014 - second International Conference on Vulnerability and Risk Analysis and Management

(ICVRAM) Liverpool, 13th-17th July 2014

P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

[email protected]

[email protected]

www.francobontempi.org

Page 36: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

3. APPLICATION TO THE “MALA RIJEKA” VIADUCT

3.12 – PSDM results with different type of retrofit

Sebastiani P.E., Padgett J.E., Petrini F., Bontempi F. (2014). Effectiveness Evaluation of Seismic

Protection Devices for Bridges in the PBEE Framework. In proceeding of: ASCE-ICVRAM-ISUMA

2014 - second International Conference on Vulnerability and Risk Analysis and Management

(ICVRAM) Liverpool, 13th-17th July 2014

P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

[email protected]

[email protected]

www.francobontempi.org

Page 37: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

3. APPLICATION TO THE “MALA RIJEKA” VIADUCT

3.12 – Fragility results

P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

[email protected]

[email protected]

www.francobontempi.org 37

Page 38: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

3. APPLICATION TO THE “MALA RIJEKA” VIADUCT

3.12 – Fragility results

In terms of damage probability, choosing the example of slight damage and

referring to the curvature ductility as EDP, the probability of damage during a

period of 50 years is: 23% for the structure without isolation, 7% for the

structure equipped with ERB, and 3% for the structure equipped with FPS

isolation.

Sebastiani P.E., Padgett J.E., Petrini F., Bontempi F. (2014). Effectiveness Evaluation of Seismic

Protection Devices for Bridges in the PBEE Framework. In proceeding of: ASCE-ICVRAM-ISUMA

2014 - second International Conference on Vulnerability and Risk Analysis and Management

(ICVRAM) Liverpool, 13th-17th July 2014

P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

[email protected]

[email protected]

www.francobontempi.org 38

Page 39: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

3. APPLICATION TO THE “MALA RIJEKA” VIADUCT

3.12 – Example of expected cost calculation

P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

[email protected]

[email protected]

www.francobontempi.org 39

Page 40: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

4. FUTURE WORK

1) Full 3D model of the Mala Rijeka Bridge

2) Loss estimation taking into account aging effects

3) Effectiveness Evaluation of different Seismic Protection Devices

4) Application to two representative categories of Highway bridges:

- Most common bridge type, i.e. short span, simply supported deck

- Less common bridge type, i.e. high piers, long span, continuous deck

DEMAND CAPACITY FRAGILITY

COMPONENT

SYSTEM

NETWORK

LOSS

? P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

[email protected]

[email protected]

www.francobontempi.org 40

Page 41: Ph.D. Thesis project of Paolo E. Sebastiani PBEE - Mala Rijeka Viaduct

KEYWORDS

PBEE

PRACTICE-ORIENTED TARGET

OPENSEES

SEISMIC ADJUSTMENT AGING

LIMIT STATES

ISOLATION (MFPS, ERB)

LCC

4. FUTURE WORK

P. E. Sebastiani – Ph.D. Student

Sapienza University of Rome - a.a. 2013/2014

[email protected]

[email protected]

[email protected]

www.francobontempi.org 41