Identification of Cracks

1.

a.

• Its form of flexural failure due to reversal of stress during earthquake.
• During stress reversal supports top experiences compression and bottom experiences tension.
• Top compresssion is managed by slab adavantge, bottom tension was not satisfied by the provided reinf.
• since the reinf. got yielded it can not be repaired.

b.

• Its beam pull out failure due to insufficient development length of reinf. development of reinf. in joints
• During earthquake the horizontal movement of structure mkes the condition worse and detavhed the beam member from column
• Providing anchorage langth between two existing concrete is very difficult. so not repairable

c.

• It is a plastic hinge failure
• The demage occured only in the joint zone first
• Cyclic lateral loading and stress reversal at the joint led to the demage
• Even the salb particiated to its best to handle the tension
• Joint can be strengthened

2.

a.

• It is a soft storey failure technically plastic hing formation
• Due to absences of 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 repairabe or not

b.

• It is pure shear failure
• Inadequate shear reinf comples concrete takes all the shear stress

c.

• It is a short column failure
• An additional slab or a beam connected to a column in mid height lead to this effect
• This lead to failue ezpecially if the connection in unintentional and not accounted in design
• The failure given in the picture is not at all repairable.