1, improper concrete mix proportion

If the concrete mixture ratio is improper, stones and cement materials are not allowed to add water, and the concrete mixture ratio will be too large or too small. If the slump of concrete is large, the fluidity of concrete will make the chamfer at the height sink due to gravity loss; If the slump of concrete is small, although it is easy to form chamfers when pouring, a large number of bubbles will be wrapped by thick concrete when mixing, and the high viscosity of concrete also increases the difficulty of bubble discharge. Therefore, improper concrete mix proportion is easy to produce honeycomb pits.

2. Poor quality of release agent

Unreasonable selection of board release agent or uneven coating of release agent are the main reasons for the honeycomb pits on the surface of concrete structure, mainly because the formwork is in direct contact with the chamfered concrete surface. If the quality of the release agent is poor, the viscosity of the release agent oil with bubbles attached to the template is high, and the oil with high viscosity will tightly adsorb the bubbles, making it difficult for the bubbles to rise and be discharged along the template.

3. Poor pouring and vibration process

Construction operators often choose to ignore vibration for convenience, which makes the concrete on the surface not dense, thus producing natural holes and irregular bubbles. Therefore, when pouring concrete, whether it is over-vibration, under-vibration or leakage vibration, it will lead to the phenomenon of honeycomb pits on the surface of concrete structure.