Detailed Micro-Modelling of Masonry under Blast and Earthquake Loads - - PowerPoint PPT Presentation

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detailed micro modelling of masonry under blast and
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Detailed Micro-Modelling of Masonry under Blast and Earthquake Loads - - PowerPoint PPT Presentation

Oct 17, 2022 106 likes •321 views

University of the German Armed Forces Munich Faculty of Civil and Environmental Engineering Institute of Engineering Mechanics & Structural Mechanics Laboratory of Engineering Informatics Univ.-Prof. Dr.-Ing. habil. N. Gebbeken Detailed

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Institute of Engineering Mechanics & Structural Mechanics Laboratory for Engineering Informatics Professor Dr.-Ing.habil. Norbert Gebbeken

University of the German Armed Forces Munich

Faculty of Civil and Environmental Engineering Institute of Engineering Mechanics & Structural Mechanics Laboratory of Engineering Informatics Univ.-Prof. Dr.-Ing. habil. N. Gebbeken

COST 26 – Urban Habitat Constructions under Catastrophic Events 16-18 September 2010

Tobias Linse Norbert Gebbeken

Detailed Micro-Modelling of Masonry under Blast and Earthquake Loads

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Institute of Engineering Mechanics & Structural Mechanics Laboratory for Engineering Informatics Professor Dr.-Ing.habil. Norbert Gebbeken

Einwirkungen: Explosionen / Detonationen Explosions, Impact, Earthquakes Assessment for masonry constructions worldwide e.g. for Embassies, Police departments Buildings for aid organizations Ordinary new and historic constructions

Masonry under (high-) dynamic Loadings

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Institute of Engineering Mechanics & Structural Mechanics Laboratory for Engineering Informatics Professor Dr.-Ing.habil. Norbert Gebbeken

Types of Masonry

Materials – Assembly – big variety

clay – adobe quarry stones clinker bricks concrete

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Institute of Engineering Mechanics & Structural Mechanics Laboratory for Engineering Informatics Professor Dr.-Ing.habil. Norbert Gebbeken

Failure modes of masonry

Bending-Failure Shear-Failure Failure due to high vertical load

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Institute of Engineering Mechanics & Structural Mechanics Laboratory for Engineering Informatics Professor Dr.-Ing.habil. Norbert Gebbeken

Failure Modes of Masonry

  • Failure of the masonry

units under tension or compression

  • Shear failure of the bed

joint

  • Tensile failure of the

masonry units or mortar joints

  • Failure under compression
  • f the masonry units

because of lateral tension

  • “stairway” failure of the

joints

  • Biaxial failure of the

masonry units

Horizontal uniaxial loading Vertical uniaxial loading Biaxial loading

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Institute of Engineering Mechanics & Structural Mechanics Laboratory for Engineering Informatics Professor Dr.-Ing.habil. Norbert Gebbeken

Failure Mechanism due to lateral deformation of the joints

Jacketed projectiles with hard cores (Silling 2007)

Tension Compression

sx / sy

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Institute of Engineering Mechanics & Structural Mechanics Laboratory for Engineering Informatics Professor Dr.-Ing.habil. Norbert Gebbeken

Failure mechanism horizontal Load

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Institute of Engineering Mechanics & Structural Mechanics Laboratory for Engineering Informatics Professor Dr.-Ing.habil. Norbert Gebbeken

Modelling Masonry - Strategies

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Institute of Engineering Mechanics & Structural Mechanics Laboratory for Engineering Informatics Professor Dr.-Ing.habil. Norbert Gebbeken

Elements of a dynamic material model strength model

elastic limit yield surface residual strength Equation of State influence of pressure – volumetric strain rate dependent effects of loading rate damage Model decrease of shear modulus and strength pressure shear

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Institute of Engineering Mechanics & Structural Mechanics Laboratory for Engineering Informatics Professor Dr.-Ing.habil. Norbert Gebbeken

Material models for Masonry Ganz„s model

  • macro model
  • several fracture surfaces
  • in plane loadings of the wall

Lourenço„s material model: Mohr-Coulomb with „Tension Cut Off“

Lourenco and Rots Journal Engineering Mechanics 1997 [LOURENCO and ROTS 1997] [GANZ 1985]

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Institute of Engineering Mechanics & Structural Mechanics Laboratory for Engineering Informatics Professor Dr.-Ing.habil. Norbert Gebbeken

Mortar - residual material strength – compressive meridian sv sr

Fracture strenght residual strenght residual strenght depends

  • n the stress state!

[BIERWIRTH 1995]

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Institute of Engineering Mechanics & Structural Mechanics Laboratory for Engineering Informatics Professor Dr.-Ing.habil. Norbert Gebbeken

Mortar - residual material strength – shear meridian

Fracture strenght residual strenght vertical load displacement

[WALLNER 2008]

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Institute of Engineering Mechanics & Structural Mechanics Laboratory for Engineering Informatics Professor Dr.-Ing.habil. Norbert Gebbeken

Mortar - residual material strength – shear meridian

[WALLNER 2008]

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Institute of Engineering Mechanics & Structural Mechanics Laboratory for Engineering Informatics Professor Dr.-Ing.habil. Norbert Gebbeken

Mortar - residual material strength

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Institute of Engineering Mechanics & Structural Mechanics Laboratory for Engineering Informatics Professor Dr.-Ing.habil. Norbert Gebbeken

Fracture surface for mortar Functions to interpolate between meridians

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Institute of Engineering Mechanics & Structural Mechanics Laboratory for Engineering Informatics Professor Dr.-Ing.habil. Norbert Gebbeken

Mortar - dynamic material properties – HAO‟s tests

DIF – Dynamic Increase Factor strain rate

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Institute of Engineering Mechanics & Structural Mechanics Laboratory for Engineering Informatics Professor Dr.-Ing.habil. Norbert Gebbeken

Material model Masonry Unit William-Warnke strength model with „Tension Cut Off“ Strain rate dependent (Hao) Residual resistance controlled by damage Model Damage Model is based on actual and maximal plastic Strain Equation of State Linear EOS

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Institute of Engineering Mechanics & Structural Mechanics Laboratory for Engineering Informatics Professor Dr.-Ing.habil. Norbert Gebbeken

Own material tests Objective: Create a Database to be able to characterize different masonry units rapidly Tests on single units:

  • Uniaxial compression with cyclic loading
  • Tension-, Bending-, Wedge-cleaving-test
  • Density / Porosity
  • Wave speed

Tests on masonry specimens: 5 units with 4 mortal joints

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Institute of Engineering Mechanics & Structural Mechanics Laboratory for Engineering Informatics Professor Dr.-Ing.habil. Norbert Gebbeken

Numerical Simulation of Masonry Walls

different support conditions can be taken into account Shear failure Bending failure Combined Failure Mechanism

Support conditions play an important role!

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Institute of Engineering Mechanics & Structural Mechanics Laboratory for Engineering Informatics Professor Dr.-Ing.habil. Norbert Gebbeken

Numerical simulation of Blast Tests

Masonry in steel frame Different thicknesses Different masonry types Loaded by blast wave Objective: Realistic results with numerical simulations

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University of the German Armed Forces Munich

Faculty of Civil and Environmental Engineering Institute of Engineering Mechanics & Structural Mechanics Laboratory of Engineering Informatics Univ.-Prof. Dr.-Ing. habil. N. Gebbeken

COST 26 – Urban Habitat Constructions under Catastrophic Events, 16-18 September 2010

Tobias Linse, Norbert Gebbeken

Thank you for your attention! Detailed Micro-Modelling of Masonry under Blast and Earthquake Loads