SCENARIO DAMAGE ANALYSIS OF RC PRECAST

INDUSTRIAL STRUCTURES IN TUSCANY, ITALY

Chiara Casotto, Vitor Silva, Helen Crowley, Rui Pinho, Roberto Nascimbene

24 fatalities, 400 injured, 20,000 homeless, $12.4B losses

Beam-column joint

Emilia Romagna Earthquake 2012: why are losses so high for such a small earthquake (5.9 Mw)?

Belleri et al. (2013)

Adana-Ceyhan (1998), Kocaeli (1999) and Duzce (1999)

60% of the industrial facilities suffered substantial damage

High ductility demand due to fixed-base crown-hinged structural scheme, and by the high inter-storey height

Damage scenario for Tuscany

EXPOSURE FRAGILITY HAZARD

Single fault rupture from Basili et al.

(2008)

Fragility curvesInventory industrial building databasefrom Ferrini et al.

(2007)

FRAGILITY

Random sampling of properties

Generation of the single structure

Geometric and Material properties and their Probability Density

Functions

BUILDING STOCK GENERATION

Random sampling of properties

Generation of the single structure

Dynamic Analyses

Storage of the damage level

enough samplings?

No

Definition of the damageLimit state

Geometric and Material properties and their Probability Density

Functions

DESIGN, MODELLING, ANALYSES

Yes

Regression analysis with damage data

Fragility curves

Yes

Random sampling of properties

Generation of the single structure

Dynamic Analyses

Storage of the damage level

enough samplings?

No

Geometric and Material properties and their Probability Density

Functions

FRAGILITY CURVE DERIVATION

Definition of the damageLimit state

Building population classification

How to represent the Italian industrial building population?

Statistical data from 649 industrial buildings inspected in Emilia Romagna and Tuscany

Type 1 Type 2

Half of the structures were not designed to seismic loads

Post-Classification

Pre-Classification

Post-Seismic Code

Pre-Seismic Code

Type 1 - Beam Length [m]

Den

sity

Type 2 - Beam Length [m]

Den

sity

Data collected by the Seismic Risk Prevention Area of Tuscany Region and Structural Analysis Section of Eucentre

Pushover analysis and Limit State definition

Dynamic analyses and damage states allocation

Input in X

c ab

c

70 records used

Analysis process

a

b

Repeat the process for the entire building population (100 frames)

Analyses results

Data fitted with a lognormal curve using with Maximum Likelihood EstimateR is the correlation coefficient: measure of the correlation between data and curve

VFR friction resistance, a friction coefficient, N axial load

following Magliulo et al. (2011), Calvi et al.(2006)

Vcnn < Vshear,max

Pre-code Vcnn= VFR = a N

Low-code Vcnn= VFR + Vsteel Collapse limit state

How to take into account connection failure as a limit state?

N reduced by 40% to account for vertical acceleration

a = 0.1-0.5Analyses run with a = 0.2, a = 0.3

PC = P(CollapseConnection) PConnection mechanism + P(CollapseFlexure)(1-PConnection mechanism)

How to account for connection collapse in regression analysis?

• Very sensitive to friction coefficient• Better estimate of the axial load reduction

a = 0.2 a = 0.3

Dynamic analysis with Vertical acceleration

How much the friction coefficient influence the results?

Connection failure with vertical acceleration

Flexural Collapse only Flexural and Connection Collapse

a = 0.2 median b R2 a = 0.2 median b R2

LS1 70.8 0.55 0.9 LS2 218.7 0.59 0.83

How much connection collapse affect the probability of collapse?

Type T1-LC-4 Topt = 1.8 s

Groundmotion

realisations

3 damage staterealisations

Damage scenario calculation with OpenQuake

Single rupture

Fragility model

Collapse estimates for a scenario Mw = 6.5 in Tuscany

M=6.5

0.0240.060.10.20.3

km

2000 ground motion fields for rock soil

slightmoderate

collapse

Collapse estimates for a scenario Mw = 6.5 in Tuscany

km

Thank you

Except where otherwise noted, this work is licensed under: creativecommons.org/licenses/by-nc-nd/4.0/

Please attribute to the GEM Foundation with a link to - www.globalearthquakemodel.org