Analysis of Tri-axial Stress-strain Conditions of Pre-stressed Masonry Corner VSB-TU, Faculty of Civil Engineering Radim Cajka Pavlina Mateckova Lucie Mynarzova Marie Stara Ostrava, Czech Republic REC 2012, Brno, Czech Republic, June, 2012

2 PRE-STRESSED MASONRY Motivation for testing REC 2012, Brno, Czech Republic, June, 2012 Church in Staric, Czech Republic

3 PRE-STRESSED MASONRY Motivation for testing REC 2012, Brno, Czech Republic, June, 2012 Old Town Hall, Ostrava, Czech Republic

4 PRE-STRESSED MASONRY Motivation for testing REC 2012, Brno, Czech Republic, June, 2012 Venezia, Italy

PRE-STRESSED MASONRY Description of testing 5 REC 2012, Brno, Czech Republic, June, 2012 Masonry corner Plan dimensions 900 x 900 mm Thickness of the wall 450 mm Height 900 mm

PRE-STRESSED MASONRY Description of testing 6 REC 2012, Brno, Czech Republic, June, 2012 Material Clay bricks Lime-cement mortar

PRE-STRESSED MASONRY Description of testing 7 REC 2012, Brno, Czech Republic, June, 2012 Vertical load and pre-stressing force MPa  50 kN  100 kN MPa  50 kN  100 kN

PRE-STRESSED MASONRY Description of testing 8 REC 2012, Brno, Czech Republic, June, 2012 Measuring of deformations Net of potentiometer sensors Short time deformations Pre-stressing in one or two directions

PRE-STRESSED MASONRY Material characteristics 9 REC 2012, Brno, Czech Republic, June, 2012 Bricks from demolished building HistAn software 6 bricks From each 4 specimen Mean value f b = MPa Variation coefficient 0.28

PRE-STRESSED MASONRY Material characteristics 10 REC 2012, Brno, Czech Republic, June, 2012 Mortar from dry mixture HistAn software 6 block specimen Mean value f m = 9.8 MPa Variation coefficient 0.04

PRE-STRESSED MASONRY Masonry compressive strength 11 REC 2012, Brno, Czech Republic, June, 2012 AntHill software using m onte carlo simulation

PRE-STRESSED MASONRY Masonry compressive strength 12 REC 2012, Brno, Czech Republic, June, 2012 AntHill software using m onte carlo simulation f mean = 7.37 MPa f k = 5.29 MPa

PRE-STRESSED MASONRY Masonry compressive strength 13 REC 2012, Brno, Czech Republic, June, 2012 Action effect from pre-stressing Pre- stressing force Anchoring plate Stress in anchoring area Ratio to vertical strength kNmMPa% x x x x x x

TESTING RESULTS Direction of pre-stressing 14 REC 2012, Brno, Czech Republic, June, 2012

TESTING RESULTS Net of measuring poitns 15 REC 2012, Brno, Czech Republic, June, 2012

TESTING RESULTS Measured deformations 16 REC 2012, Brno, Czech Republic, June, 2012 Vertical load MPa, pre-stressing force 100 kN

TESTING RESULTS Measured deformations 17 REC 2012, Brno, Czech Republic, June, 2012 Vertical load MPa, pre-stressing force 100 kN

MASONRY NUMERICAL MODELLING Basic ways of modelling 18 REC 2012, Brno, Czech Republic, June, 2012 Complicated with following factors: Different material properties of basic components Different dimensions of basic components Narrow dimension of mortar joint Geometrical arrangement of bricks Different structural response for different load action direction Interaction between components Quality of manufacturing Environmental influence

MASONRY NUMERICAL MODELLING Basic ways of modelling 19 REC 2012, Brno, Czech Republic, June, 2012 Three basic approaches: Detailed micromodel Simplified micromodel Macromodel

MASONRY NUMERICAL MODELLING Micromodel 20 REC 2012, Brno, Czech Republic, June, 2012 Ansys software: Solid 45 Link 8

MASONRY NUMERICAL MODELLING From micromodel to macromodel 21 REC 2012, Brno, Czech Republic, June, 2012

MASONRY NUMERICAL MODELLING From micromodel to macromodel 22 REC 2012, Brno, Czech Republic, June, 2012 Input and output parameters Material Modulus of Elasticity [GPa] Shear modulus [GPa] Poissons’ ratio [-] Input Bricks 290/140/65 15,000,15 Mortar 10MPa 10,000,2 Output Masonry x direction 13,963,650,202 Masonry y direction 14,005,560,198 Masonry z direction 13,844,300,197

MASONRY NUMERICAL MODELLING Macromodel 23 REC 2012, Brno, Czech Republic, June, 2012 Ansys software: Solid 45 Link 8

MASONRY NUMERICAL MODELLING Micromodel x Macromodel 24 REC 2012, Brno, Czech Republic, June, 2012 Section in place of upper pre-stressing bar

25 Testing of masonry corner exposed to tri-axial load  Small measured deformations  Unexpected course of deformation Testing of material properties  Relatively high strength of bricks  High variation coefficient Numerical modelling of masonry  Calculated deformation respond to measurements  Micromodel reflect the expeceted way of str. break CONCLUSION REC 2012, Brno, Czech Republic, June, 2012

Thanks for attention! VŠB-TU, Faculty of Civil Engineering Ostrava, Czech Republic REC 2012, Brno, Czech Republic, June, 2012