Types and Reasons of Cracks in Concrete Column

Non Structural Crack and Structural Crack

After a building has been constructed, it is vital to have proper management to maintain the building. This is to improve the appearance of the building and ensure the health and safety of the users [1]. Not only that, regular maintenance is much more cost effective than fixing a problem after it has already failed [1]. Having said that, the maintenance of a building can be complicated, managers will face many maintenance challenges throughout the process. The management team must able to identify these challenges and determine the most effective and efficient solutions to overcome them. Therefore, in this article, 6 major building maintenance challenges will be discussed along with their respective solutions.

Types of Crack in Concrete Column

Column is an important element in the building framing structure and it transfers the load from the upper floor towards the foundation. Cracks in the column can be categorised according to their crack pattern or propagation. The 4 types of cracks in the concrete column are listed below [3] [4]:

a) Diagonal Crack:

The crack propagation is diagonal along the entire column face. This crack formed due to incorrect design causing the column to have inadequate loadcarrying capacity. Diagonal cracks in the column indicate that the column may have not enough reinforcement area or inadequate cross-section of the column. Figure 1 shows

b) Horizontal Crack:

Horizontal cracks within the concrete column are typically seen on the beam-column joint and on the column face where tensile stress is high. Columns with insufficient moment restrain, low reinforcement area or incorrect arrangement of the diagonal crack in the concrete column.

Figure 1: Diagonal Crack In The Concrete Column [3] [4]

Figure 2: Horizontal Crack in The Concrete Column [3][4]

c) Splitting Crack:

Splitting cracks at the concrete columns are short and parallel vertical cracks of varying width. These types of cracks can occur in columns with insufficient steel bar reinforcement and low concrete strength. Splitting crack happens as the load acting on it reaches its ultimate load-bearing capacity. In other words, this is a compression failure of the concrete column. An example of the splitting crack in the concrete column is shown in Figure 3.

Figure 3: Splitting Crack in The Concrete Column [3][4]

d) Corrosion Crack:

Corrosion crack is a crack formed by rusting the concrete reinforcement bar. The crack propagation follows the pattern or the line of the steel bar. The reinforcement bar normally corrodes due to the inadequate concrete cover, hairline cracking on the concrete surface, and exposure to high humidity or chemical attack. If these types of cracks cannot be properly treated, the degradation of the steel reinforcement bars can worsen exponentially. Figure 4 shown the corrosion cracks in the concrete column.

Figure 4: Corrosion Crack in The Concrete Column [3][4]

Conclusion

Crack in the column can be non-structural or structural crack and can be categorised according to its crack pattern. Structural cracks (crack width of more than 2.00 mm) in the column are difficult to handle because it serves a vital role in building frame structure. The rectification work of cracks should be based on its type and the root cause of the failure. It is recommended to appoint a competent or professional contractor with engineering background to carry out proper defects assessment in order to recommend the best solution for defect repairing.

References

[1] Arvind Rajabather (2016). Investigation of Cracks In Buildings. Forensic Structural Engineering, Vit Chennai Campus,
Volume: 1. Retrieved on 26th May 2021 from
https://www.researchgate.net/publication/319630328_INVESTIGATION_OF_CRACKS_IN_BUILDINGS
[2] Lai Woon Fatt (2020). Type Of Cracks On Buildings. IPM Group. Retrieved on 26th May 2021 from https://ipm.my/type-ofcracks-on-buildings/
[3] Madeh Izat Hamakareem. 4 Types of Cracks in Concrete Columns and their Causes. The Constructor, Civil Engineering
Home, Building Technology Guide. Retrieved on 25th May 2021 from https://theconstructor.org/concrete/types-cracks-concretecolumns/26433/
[4] Civil Engineering (2019). Types Of Cracks In R.C.C Columns. Retrieved on 25th May 2021 from
https://www.constructorsknowledge.com/2019/10/types-of-cracks-in-rcc-columns.htm