Majority of cracks occur when the building or its components or the material of which the building is made up of is subjected to forces that are greater than those it can withstand. Cracks may also occur if the materials used in the building is of poor quality and the construction is not carried out in accordance with relevant drawings, prescribed job specifications and in a workmanlike manner.

Cracks can be broadly classified in two categories; i.e., structural cracks and non-structural cracks.

There are various reasons for developing these cracks. Such as cracks due to

• excessive shear force
• excessive moment
• tension force
• thermal stresses
• temperature variations
• elastic deformation and creep
• effect of chemical reaction
• movement of ground
• excessive axial force
• vegetation
• the effect of adjacent construction

Much of these cracks are developed due to faulty design, overloading or other similar fractures. Cracks in a structure give an impression that the structure is getting unsafe.

ACI Code includes some safety factors to eliminate cracks. Some precautionary measures need to be taken to eliminate cracks. Causes and prevention of cracks in structures have been described in this thesis.