Insufficient vibration or consolidation during concrete placement can lead to voids or excessive air in interface between the two concrete sections (creating weakened bonding results and leading to cold joint formation). This is known as a concrete cold joint. The visible change between the two concrete surfaces could be a slight difference in color or texture. A cold joint is a visible or structural separation that occurs when fresh concrete is poured against previously placed concrete that has already begun to set. Instead of forming a monolithic (single, unified) structure, the two layers fail to bond properly. Cracking Cold joints often become points where cracks initiate and propagate. A residential project faced leakage issues in an underground water tank.
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