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8 common types of cracks in concrete D
uring construction or even after completion, various types of cracks in concrete may appear on the building due to a number of factors. Cracks in concrete usually develop cracks whenever the stress is more than the strength. Stress is normally caused by external loads and forces. In reinforced concrete, cracks may occur due to the inadequate size of their section or reinforcing steel, and corrosion in reinforcement. Below are the main types of cracks in concrete; 1. Diagonal Cracks
beam-column junction. Horizontal columns also appear on the column face where tensile stress is large. Columns with insufficient reinforcements, inadequate moment of resistance capacity, and disposition of installed reinforcement are prone to horizontal cracking. This is largely due to the effect of uniaxial bending, direct load, and shear force. Horizontal cracks may cause a substantial reduction in the column’s shear strength. This may lead to great risk and compromise the strength of the whole structure. 3. Splitting Cracks
Diagonal Cracks
Diagonal cracks may appear anywhere along the height of the reinforced concrete. These types of cracks always involve the entire face of the column. Diagonal cracks in concrete columns are mainly caused by insufficient cross-section, the inadequate load-carrying capacity of the columns, and inadequate reinforcement steel. Diagonal cracks need to be addressed urgently as they may compromise the strength of the entire structure within a short time.
Splitting Cracks Splitting cracks appear in form of short parallel vertical cracks in reinforced concrete columns. They have varying widths. These cracks are common in columns with low concrete quality and insufficient steel reinforcement. In reinforced concrete, splitting cracks mainly appear as a result of reaching its maximum load-carrying capacity. The ultimate load-carrying capacity of a column is surpassed when the cross-section of the concrete is inadequate or reinforcement ratio is insufficient or a combination thereof.
2. Horizontal Cracks
4. Corrosion Cracks
Horizontal Cracks In reinforced concrete, horizontal concrete cracks mainly appear at the
Corrosion cracks Corrosion cracks mainly appear along the line of reinforcements of
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CR | Jan/Feb 2021
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