Identification of Cracks
- What is the mode of failure or damage of the beams in the figure above? Are the damages repairable? Elaborate
1ST PICTURE
- THE FLEXURAL FAILURE DUE TO REVERSAL OF STRESS DURING SEISMIC EVENT
- THE TOP PORTION EXPERIENCES COMPRESSION AND THE BOTTOM EXPERIENCES COMPRESSION AT SUPPORT DURING STRESS REVERSAL
- THE PROVIDED REINFORCEMENT WAS NOT SATISFIED FOR BOTTOM TENSION HOWEVER THE COMPRESSION AT TOP HAS AN ADVANTAGE OF SLAB SUPPORT
- THERE IS A FAILUE OF REINFORCEMENT AT BOTTOM SO IT CANNOT BE REPAIRED
2ND PICTURE
- DEVELOPMENT LENGTH PROVIDED WAS INSUFFICIENT AT JOINTS
- DURING SEISMIC EVENT THE BEAM IS DETATCHED FROM THE COLUMN
- SHEAR DEFORMATION GOVERNS IN BEAM - COLUMN JUNCTION
- FORMATION OF PLASTIC HINGE MUST OCCUR AT END OF BEAMS(NOT AT B-C JUNCTION)
- NOT REPAIRABLE
3RD PICTURE
- FAILURE DUE TO PLASTIC HINGE
- BEAMS AND SLAB HAVING CRACKS AT JOINT WIDTH
- CAN BE REPAIRED WITH STRENGTHENING
2.
1ST PICTURE
- PLASTIC HINGE FORMATION FOR SOFT STOREY BUILDING
- THERE ARE NO WALLS AND NO DAMAGE IN THE BEAM
- DEPENDING ON THE DEVELOPMENT OF CRUSH CONCRETE IT IS POSSIBLE TO REPAIR IT
2ND PICTURE
- CAUSE OF SHEAR FAILURE
- INADEQUATE SHEAR REINFORCEMENT PROVIDED SINCE THE SPACING PROVIDED IS HIGH AND THE LONGITUDINAL REINFORCEMENT PROVIDED IS INTACT HENCE CONCRETE FAILURE
- CANNOT BE REPAIRED
3RD PICTURE
- SHORT COLUMN FAILURE
- EXTRA SLAB OR BEAM ADDED TO A COLUMN IN MID LENGTH CAUSES THIS FAILURE
- NO REPAIR POSSIBLE