Identification of Cracks

1)A

BASED ON THE OBSERATION

• The reinforcement are exposed.
• concrete has been crushed.
• The reinforcement shows up the sign of rupture.
• top rod seems to be ok.
• cracks appears on the bottom yeilding occurs.

ANSWERS

it is form of flexural failure due to reversal of stress during earthqauke during the stress reversal, support top experinece compression and bottom experience tension.

top compression is managed by slab advantage. bottom tension was not satisfied by the provided reinforcement since the reinforecement got yeilded it can not be repaired.

1)B

BASED ON THE OBSERATION

• Cracks along with the beam edge.
• Cracks seems to have developed through the structure as it looks much wider.
• Beam looks seperated from the column at joints.
• Concrete is not severely crushed.

ANSWERS

it is a beam pull out failure due to insufficent development length of reinforcement in joints during earthqauke the horizontal movement of structure makes this condition worse and detached the beam from column.

providing anchorage lengthy between two existing concrete is very difficult. not repairable.

1)C

BASED ON THE OBSERATION

• Cracks are at the joint of the cloumn and beam.
• Cracks in beam developed its entire width.
• Slab also developed more cracks along the beam width direction.

ANSWERS

IT is a plastic hinge failure

the danmage ocuured only in the joint zone

Cyclic lateral loading and stess reversal at the joints led to damage. even the slab transferred its best to handle the tension(slab is severly cracked means it has undergone tensionn with its flange condition) but unable to contol the damage.

The joints can be strengthened.

2)A

BASED ON THE OBSERATION

• Concrete has damaged at top of a column.
• Concrete damaged all around the cloumn face.
• Beams looks safe.
• The location of column looks at edge of the building.
• No walls are built along the column means it is probably at ground floor, for parking car movement access.

ANSWERS

It is a soft storey failure, technically plastic hinge formation due to infill walls at the ground floor, the plastic hinge forms at the top of ground storey column during lateral movement.

Based on the development of crush of concrete. it can either be repairable or Non repairable.

2)B

BASED ON THE OBSERATION

• Concrete developed complete breakage.
• vertical reinforcement are in intact.
• spacing of reinforcement looks wider(which means probably lesser shear rebar provided)

ANSWERS

it is a pure shear failure. its fully crushed

inadequate shear reinforcemnt compels can concrete takes all the shear stresses.

hence its cannot be repaired.

2)C

BASED ON THE OBSERATION

• There is no bonding with the beam and the column.
• Column failed compltely
• failure at the top of the column.
• There are two slabs connected to the column probably one at mid height of the column.
• The wooden piles might be post failure support after column failed, providing temprorary prop to avoind collapse of the entire structure.

ANSWERS

it is a short column failure.

An addtional slab or a beam connected to a coumn in mid height leads to this effect.

this leads to failure especially if the connection is unintentional and not accounted in design.

the picture clearly its cannot be repaired.