Seismic assessment of historical masonry buildings with nonlinear static analysis

Seismic assessment of an historical masonry

building with nonlinear static analysis

Sapienza University of Rome

F. Bucchi, S. Arangio, F. Bontempi

Cagliari, September 5th 2013

StroNGER s.r.l.

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SEISMIC ASSESSMENT OF AN HISTORICAL MASONRY BUILDING

WITH NONLINEAR STATIC ANALYSISF. Bucchi, S. Arangio, F. Bontempi

Introduction

Part I

Conclusions

Part II

Nonlinear static analysis with different commercial codes

Outline

Seismic assessment of masonry historical buildings

Case study:

Analysis of Camponenschi Palace (L’Aquila, Italy)

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Introduction

Part I

Conclusions

Part II


Outline


Case study:


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Structural assessment of masonry buildingsIn

troduction

Simplified Analysis Method (SAM)[Magenes]

POR[Tomazevic]

Equivalent struts[Calderoni et al.]

SISV[D’Asdia et al.]

Macroelements with springs[Caliò et al.]

Macroelements[Gambarotta et al.]

1D

2D

Detailed microelements 3D finite element models

3D

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Introduction

Part I

Conclusions

Part II


Outline


Case study:


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Nonlinear static analysis of a three dimensional buildingP

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SAP2000 Muri

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Nonlinear static analysis with SAP2000

Part

I

PIER

SPANDRELJOINT

Plastic hinges

“weak” spandrel “strut” spandrel floor with shell elements

control node

Part

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Nonlinear static analysis with 3Muri

The panels are

schematized with

macro-elements with

8 DOFs

Panel Macro-element

Integer

Plastic (shear)

Failure (shear)

Plastic (Bending moment)

Failure (Bending moment)

Failure (Compression)

Failure (Tension)

Failure (in elastic phase)

Part

I

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“weak” spandrels: comparison of the modeling hypothesis

a) b)

� The nodes are connected with an

internal rigid constraint

� Diaphragm constraints between the

adjacent nodes

2. CONNECTIONS

� “Simple” panel

1. WALLS

� frames; plastic hinges with low Vu e

Mu (“weak” behavior)

� Weak connection between joists and

walls

a) wood floor not modeled

b) wood floor modeled with shell elements

3. WOOD FLOOR

SAP2000Muri

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I

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“strut” spandrels: comparison of the modeling hypothesis

a) b)

� The nodes are connected with an

internal rigid constraint

� Diaphragm constraints between the

adjacent nodes

2. CONNECTIONS

� Panel with chains

1. WALLS

� frames; plastic hinges with Vu e Mu

defined in accordance with NTC2008

� Weak connection between joists and

walls

a) Rigid floor modeled with a strut

b) Rigid floor modeled with shell elements

3. WOOD FLOOR

SAP2000Muri

Part

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Plastic hinges - SAP2000P

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a) b) c)

“WEAK” SPANDRELS

“STRUT” SPANDRELS

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Nonlinear static analysis with 3MuriP

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Integer

Plastic (shear)

Failure (shear)

Plastic (Bending moment)

Failure (Bending moment)

Failure (Compression)

Failure (Tension)

Failure (in elastic phase)

Almost all the spandrels show

plastic bending behavior.

The piers work as cantilever

beams.

“WEAK”

SPANDRELS

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Comparison of the resultsP

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Introduction

Part I

Conclusions

Part II


Outline


Case study:


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Camponeschi PalaceP

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Camponeschi Palace – SAP2000 ModelP

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II Properties of the masonry

KL2 CF= 1.2

w 18 kN/m3

E 1202 N/mm2

G 300 N/Cm2

fM 270 N/mm2

fvm0 6 N/cm2

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Results of the nonlinear static analysisP

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0

500

1000

1500

2000

2500

3000

0 0,02 0,04 0,06 0,08 0,1 0,12 0,14

Sh

ear

[kN

]

Displacement - control node #31 [m]

Distribution of forces proportional to

seismic masses

Distribution of forces proportional to

equivalent static forces

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Plastic hingesP

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Plasticization of the

spandrels

Plasticization of some piers

Plasticization of all the piers of the first level

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[From Gattulli,2011]

Comparison with the results obtained with 3MuriP

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Introduction

Part I

Conclusions

Part II


Outline


Case study:


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Conclu

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Two commercial codes for nonlinear static analysis of masonry buildings have

been compared:

• Both codes are able to reproduce the failure mechanisms;

• The results are very sensitive to the modelling hypothesis;

• The kind of floor strongly influences the response of the structure;

Conclusions and future studies

Case study: Camponeschi Palace

• The codes are in substantial accordance on the

failure mechanisms and they are coherent with

the observed damages.

• In order to obtained more detailed results a

complete 3D model is needed.

• The current work is focused on the

comparison of the results obtained

with the entire model developed

with 3Muri and Strand7

email: [email protected][email protected]@uniroma1.it

This research was partially supported by StroNGER s.r.l. from the fund “FILAS - POR FESRLAZIO 2007/2013 - Support for the research spin off”.

Technology

Seismic assessment of historical masonry buildings with nonlinear static analysis