Building Cracks

Alya Abdulla
Jan 25, 2022, 9:45:16 AM

Buildings and other built structures defects, movement of the ground, foundation failure, decay of the building fabric, and so on. If a structure is unable to accommodate this movement, cracking is likely to occur. The appearance of distortions and cracks can be visually unattractive and disconcerting for occupants, and if left untreated they can affect the integrity, safety and stability of the structure. Effective treatment requires first that the causes of cracking are understood. Only then can a strategy for repair be implemented.

Causes of cracks:

1- Structural design reasons: An error in calculating the sum of fixed and loads in the building, based on which the measurement of columns and roof-carrying bridges were designed.

2- Executive structural reasons: a mistake in the use of sound building materials during implementation or a shortcoming in the methods of dealing with the elements of materials that require supports, time to gain strength or the addition of chemical bonding materials to the structural elements.

3- Causes resulting from environmental factors: such as changes in temperature, wind, rain, wet resulting from groundwater or air humidity.

Types of cracks in buildings are cracks in the walls are wavy lines that may be superficial or recessed inward:

1- Vertical cracks: they usually occur between the walls and the adjacent concrete columns due to the different density coefficient. It is caused by environmental factors such as expansion and contraction, the age of the building, and it may be a shortening of the network linking the wall and the column before the survey process.

2- Horizontal cracks: They usually occur between the walls and the upper bridges bearing the ceilings, and the causes are the same as in the vertical cracks.

3- Sloping cracks: They are one of the most dangerous cracks that affect the structure of the building and are in the form of a sloping wavy line, thresholds, or collapse in concrete. Its causes are many, including a subsidence of part of the building’s foundations because of loosening the ground due to leaking sewage pipes, water flooding, rain, or stripping of reinforcing steel. Resolving the problem includes excavating part of the building's foundation and re-pouring the foundation with concrete mix. This traditional technique can be replaced by using stretchable chemicals to fill the spaces between concrete and soft ground with help of laser technology.

4- Wall swelling: It is the fall of pieces of the surveyor’s cement layer or the collapse of pieces of tiles as a result of the erosion and expansion of rebar due to moisture intrusion, which exposes the concrete to swelling and separating its elements. The treatment of the problem includes stopping the cause of moisture from repairing water pipe connections and then removing the surveyor layer or tile and cracking the concrete cover surrounding the rust of rebar, and the process of cleaning the rebars and sanding them well to remove the rust layer, if the loss of iron is equivalent to less than 20%, paint is used Epoxy to protect iron and the cohesion of modern concrete with the old. But if the percentage of loss of reinforcing steel is greater than 20%, it is necessary to break the concrete, put new reinforcing steel, and re-pour the area with concrete.

In conclusion, it is necessary to take adequate preventive measures as the construction project is expensive and it is difficult to compensate for this cost. Therefore, care must be taken during construction and correct specifications and practices must be followed to prevent the appearance of cracks in addition to conducting periodic inspections and maintenance of the entire building.