Identification of Cracks
1
A
Observations
The reinforcement is exposed
The concrete is apalled beyond the reinforcement which is rupture
The top portion of the beam is good
Crack is developed from bottom to top means rebar yielding occurs
Mode of damage
It is a flexural failure due to earthquake
During stress reversal support top experiences compression and bottom experiences tension
The top is managed by slab and bottom tension is satisfied by te provided reinforcement
It cannot be repaired because the reinforcement got yielded
B
Observations
Cracks are absorbed along the beam coloumn edge
They are wider and developed through the structure
Concrete is not severly crushed
Mode of damage
It is a beam pull out failure because of the insufficient development length of reinforcement at the joints
During the earthquake the horizontal movement of structure makes the condition work and detached the beam member from coloumn
Providing anchorage is difficult so it is not repairable
C
Observations
Cracks are at exactly at coloumn joints and they are developed through entire width
Slab is also developed cracks along the beam width
Mode of damage
It is of plastic hinge failure
Here the damage is occured in the joint zone
Cyclic lateral loading and reversal at the joint led to the damage
Slab is also undergone a lot of tension but cannot controll the damage
The joint can be strengthened
2
A
Observation
Concrete is damaged at the top of the coloumn and all around the coloumn face
The beam is safe and it seems to be in the edge of the building
It might be in the ground floor becaus it is empty and maybe used for parking ...
Mode of damage
It is a soft storey failure and techinically plastic hinge failure
Due to absence of infill wall at GF the plastic hinge forms at the top of ground storey coloumn during lateral movement
Repairing depend on the crush of the concrete
B
Observation
Concrete developed complete breakage diagonally
Longitudinal reinforcement is inact
Shear reinforcement is wider as it seems
Mode of damage
It is a shear failure
Inadequate of shear reinforcement comples concrete takes all the shear stress
C
Observation
The coloumn is failed completely
Failure is at thetop of the coloumn
Two slabs are connected to the coloums at mid nd top
Mode of damage
It is a short coloumn failure
Addition of beam is connected at mid height leads failure
It occurs dur to if connections are unintentional and are not in the design
Here it is not at all repairable