Identification of Cracks

1.The objective the above question is to identify the type of failure based on the given pictures.

a)Failure due to improper nominal cover develops large deformation of column/walls.If the size of nominal cover less than the diameter of the bar also this type of failure occurs.

b)Failure due to improper bonding and curing.the load bearing capacity and serviceability performance of reinforced concrete structures depend on the highly on the interaction between reinforcing bars and the surrounding concrete.over time the bond can degrade due to deterioration of reinforcement and/ surrounding concrete.

This type of failure is also happens with improper curing which results in cracks along the wall.

c)Tension failure/Ductile failure and beam-column junction failure due to earthquake. This type of load simply occurs when stress on a component exceeds the strength of the material. Junctions are most prone areas to earthquake.

2.AIM: Identifying type of cracks from above figures.

a)Failure due to flexural compression in column and due to bending moments. flexural tension failure initiated by yielding of steel reinforcement followed by crushing of concrete at compression side of the beam. This type of failure avoided by providing high compressive strength concrete.

b)Shear failure of the column/ failure by rupture, this type of failure occurs due to massive loads like wind and seismic loads. In general,failure of columns due to shear can be identified as the failure of design. This type of loads can be avoided by providing standard shear attachments to the structures.

c)Damage due to crushing.This type of damage can be avoided by provinding high compressive stength concrete and strong steel reinforcement.