Modelling of Concrete Structures Subjected to Blast and Fragment Loading.pdf
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CHALMERS Modelling of Concrete Structures Subjected to Blast and Fragment Loading ULRIKA NYSTROM Akademisk avhandling som for avlaggande av teknologie doktorsexamen vid Chalmers tekniska hogskola forsvaras vid offentlig disputation den 21 februari 2013, klockan 10.00 i VK-salen, Sven Hultins gata 6, Goteborg. Avhandlingen forsvaras pa svenska. Fakultetsopponent ar professor Anders Ansell, Kungliga Tekniska hogskolan i Stockholm. Institutionen for bygg- och miljoteknik, Avdelningen for konstruktionsteknik, Betongbyggnad CHALMERS TEKNISKA H6GSKOLA 412 96 Goteborg Telefon 031-772 1000
Transcript of Modelling of Concrete Structures Subjected to Blast and Fragment Loading.pdf
CHALMERS
Modelling of Concrete Structures
Subjected to Blast and Fragment Loading
ULRIKA NYSTROM
Akademisk avhandling som for avlaggande av teknologie
doktorsexamen vid Chalmers tekniska hogskola forsvaras vid
offentlig disputation den 21 februari 2013,
klockan 10.00 i VK-salen, Sven Hultins gata 6, Goteborg.
Avhandlingen forsvaras pa svenska.
Fakultetsopponent ar professor Anders Ansell,
Kungliga Tekniska hogskolan i Stockholm.
Institutionen for bygg- och miljoteknik,
Avdelningen for konstruktionsteknik, BetongbyggnadCHALMERS TEKNISKA H6GSKOLA
412 96 Goteborg
Telefon 031-772 1000
Contents
ABSTRACT I
SAMMANFATTNING II
LIST OF PUBLICATIONS III
PREFACE V
CONTENTS VI
NOTATIONS VIII
1 INTRODUCTION 1
1.1 Background 1
1.2 Aim and objectives 1
1.3 Scientific approach 2
1.4 Methodology 3
1.5 Limitations 5
1.6 Research significance 7
1.7 Outline ofthe thesis 8
2 CONCRETE MATERIAL BEHAVIOUR 9
2.1 Material testing 9
2.2 Uniaxial tension and compression 9
2.2.1 Static behaviour 9
2.2.2 Dynamic behaviour 12
2.3 Influence ofconfining pressure 14
2.3.1 Static behaviour 14
2.3.2 Dynamic behaviour 17
3 BLAST AND FRAGMENT LOADS AND THEIR EFFECT ON CONCRETE
STRUCTURES 19
3.1 General 19
3.2 Load characteristics at target 20
3.2.1 Blast load 20
3.2.2 Fragment load 22
3.2.3 Combined loading 23
3.3 Load effect on reinforced concrete structures 24
3.3.1 General 24
3.3.2 Modes of failure 25
3.3.3 Effect of reinforcement 26
3.3.4 Effect of steel fibres in concrete on local response 28
3.3.5 Effects of combined loading 29
VI CHALMERS, Civil and EnvironmentalEngineering
4 DYNAMIC ASPECTS OF WAVE PROPAGATION 32
4.1 General 32
4.2 Inertia and wave propagation effects 33
4.3 Shock waves 34
4.3.1 Introduction 34
4.3.2 Shock wave formation 34
4.3.3 Shock transition - a thermodynamic processes 38
4.3.4 Rankine-Hugoniotjump conditions 40
4.3.5 Release from shocked state 41
5 NUMERICAL MODELLING AT HIGH DYNAMIC LOADING 43
5.1 Introduction 43
5.2 Solution techniques 44
5.2.1 Numerical solution 44
5.2.2 Lagrange solver 45
5.2.3 Material modelling 46
5.2.4 Large strain and stress theory 49
5.3 Material models for concrete 49
5.3.1 Background 49
5.3.2 RHT model 51
6 THE CONCRETE DAMAGE PLASTICITY MODEL 2 59
6.1 Development process 59
6.2 Needs and requirements 61
6.3 Theoretical description 63
6.4 Implementation 64
6.5 Verification 69
6.6 Validation 70
6.7 Evaluation 71
7 CONCLUSIONS 74
7.1 General conclusions 74
7.2 Suggestions for future research 75
8 REFERENCES 77
APPENDIX A EQUATION OF STATES FOR SOLIDS
APPENDIX B CONVERSION TO TRUE STRAINS AND STRESSES
CHALMERS, Civil andEnvironmental Engineering VII
