Identification of Cracks

Ans. 1

AIM- idntification of diffrent types of failure and cracks given in the pictures

a).

• it's form of flexural failure due to reversal of stress during earthquake
• During stress reversal support top experience compression and bottom experience tension
• Top compression is managed vy slab advantage. but bottom tension was not satisfied by yhe provided reinforcement
• since the reinforcement got yielded it can not be repaired.

b)

• its Beam pull out faulure due to insufficient developement length of reinforcement joint .
• During earthquake the horizontal movement of structure makes condition worse and detached the vean member.
• Providing anchorage length between two existing concrete is very difficult . so that its not repairable.

C)

• its Plastic hinge failure
• The damage occurred only in the joint zone first of all
• Cyclic lateral loading & stress reversal at the joints led to the damage
• EVen the slab participated to its best to handle the tension (slab is severely cracked means it has undergone tension with its flange condition but unable to control teh damage
• The joint can be strengthened.

Ans.2

a)

• its a soft storey failure Technically plastic hinge formation
• Due to absenc of infill walls at the ground floor the plastic hinge form at the top of ground storey columns during lateral movemement
• Based on teh development of the crush concrete it can either be repairable or Non- repairable

b)

• Its a Pure Shear failure
• inadequate shear reinforcement compels concrete takes all the shear stresses

c)

• Its a short column Failure
• An Additional slab or a beam connected to a column in mid-height leads to this effect
• This leads to failure especially if the connection is unintentional and not accounted in design
• the failure given in the picture is not at all repairable.