Structural Masonry An Experimental/ Numerical Basis for Practical Design Rules (CUR Report 171)

PREFACE -- SUMMARY -- SYMBOLS -- 1 INTRODUCTION -- 1.1 General -- 1.2 Purpose and framework of the research -- 2 TESTING OF MATERIALS -- 2.1 General -- 2.2 Materials, their processing and coding -- 2.2.1 Materials -- 2.2.2 Manufacturing of specimens -- 2.2.3 Terminology -- 2.2.4 Coding -- 2.3 Mechanical properties of masonry in compression -- 2.3.1 Specimens -- 2.3.2 Testing -- 2.3.3 Progress of the test -- 2.3.4 Compressive strength -- 2.3.5 Elastic modulus -- 2.3.6 Transverse contraction -- 2.4 Tension tests -- 2.4.1 Specimen -- 2.4.2 Testing -- 2.4.3 Tensile strength of the joints and the units -- 2.4.4 Elastic moduli of the joints in tension -- 2.4.5 Fracture energy and ‘post peak’ behaviour -- 2.4.6 Influence of the real (net) bonding surface -- 2.5 Joint shear tests -- 2.5.1 Specimen -- 2.5.2 Testing -- 2.5.3 Tensile tests with shear tests -- 2.5.4 Shear strength -- 2.5.5 Shear stiffness or shear modulus of the mortar joint -- 2.5.6 Friction coefficient -- 2.5.7 Cohesion-softening and shear crack energy -- 2.5.8 Dilatancy -- 2.5.9 CEN tests 2.6 Conclusions -- 2.6.1 Conclusions with regard to the compression tests -- 2.6.2 Conclusion with regard to the tension tests -- 2.6.3 Conclusion with regard to the shear tests -- 2.6.4 General conclusions -- 3 NUMERICAL MODELS IN DIANA -- 3.1 General -- 3.2 Non-linear finite element method -- 3.2.1 Points of departure and types of elements -- 3.2.2 Solution procedure for non-linear material behaviour -- 3.3 Joint-unit discontinuum models -- 3.3.1 Points of departure -- 3.3.2 Modelling of units, joints and areas of adhesion -- 3.3.3 Linear-elastic behaviour -- 3.3.4 Discrete crack formation -- 3.3.5 Coulomb friction -- 3.3.6 Combination cracking and Coulomb friction -- 3.3.7 Alternative formulations -- 3.4 Super elements -- 3.5 Anisotropic continuum models for masonry as a composite -- 3.5.1 Points of departure -- 3.5.2 Orthotropic-elastic behaviour -- 3.5.3 Smeared cracking -- 3.5.4 Plasticity -- 3.6 Sense and nonsense with regard to the scatter in material properties -- 4 EVALUATION AND VERIFICATION STUDIES WITH DIANA -- 4.1 General -- 4.2 Verification study of piers in shear -- 4.2.1 Experimental results -- 4.2.2 Modelling -- 4.2.3 Numerical results -- 4.2.4 Evaluation of modelling aspects -- 4.2.5 Striking influence of dilatancy -- 4.2.6 Conclusions -- 4.3 Evaluation study of wall parts in tension -- 4.3.1 From micro to macro via numerical simulations -- 4.3.2 Analytical reference data -- 4.3.3 Numerical modelling -- 4.3.4 Results -- 4.3.5 Comparison with analytical formulations -- 4.3.6 Influence of dilatancy -- 4.3.7 Influence of the type of masonry (calcium silicate unit /clay unit) -- 4.3.8 Influence of dimensions of units, blocks and elements -- 4.3.9 Influence of top load -- 4.3.10 Influence of open head joints -- 4.3.11 Conclusions -- 5 NUMERICAL STUDIES WITH UDEC -- 5.1 Distinct element method -- 5.1.1 Division into blocks and interfaces -- 5.1.2 Geometrical non-linearity -- 5.1.3 Explicit dynamic solution procedure -- 5.1.4 Constitutive models -- 5.2 Evaluation study of narrow pier -- 5.2.1 Modelling -- 5.2.2 Results -- 5.3 Evaluation study of wide pier with opening -- 5.3.1 Modelling -- 5.3.2 Results -- 5.4 Comparison of distinct element method with finite element method -- 6 CASE STUDY CRACKING BEHAVIOUR OF WALLS UNDER RESTRAINED SHRINKAGE -- 6.1 Introduction -- 6.2 Definition of the problems -- 6.2.1 Behaviour of walls with obstructed shrinkage -- 6.2.2 Influencing parameters -- 6.2.3 Present-day knowledge in the analytical and experimental field -- 6.3 Numerical research -- 6.3.1 Modelling -- 6.3.2 Results -- 6.4 Influence of boundary conditions -- 6.4.1 Axial degree of restraint -- 6.4.2 Bending stiffness of the restraint -- 6.4.3 Two-sided restraint -- 6.4.4 Friction /slip and top load -- 6.5 Influence of material parameters -- 6.6 Influence of geometry: Wall length -- 6.7 Conclusion: The step to calculation rules -- 6.8 Practical relevance -- 7 CASE STUDY PIER-MAIN WALL CONNECTIONS -- 7.1 Introduction -- 7.2 Present-day knowledge in the analytical field -- 7.3 Present-day knowledge in the experimental field -- 7.4 Numerical modelling -- 7.5 Numerical results -- 7.6 Conclusion: The step to calculation rules 8 CONCLUDING REMARKS -- APPENDIX: INFLUENCE OF WALL LENGTH ON STRESS -- DISTRIBUTION WITH RESTRAINED SHRINKAGE -- REFERENCES.

Biography

CUR Centre for Civil Engineering Research and Codes. TNO Building and Construction Research, Rijswijk, Netherlands.