Concrete pouring should be carried out in layers so that the commercial concrete can be vibrated and compacted, and the upper concrete should be poured and vibrated before the lower concrete solidifies. The thickness of the concrete pouring layer should meet the regulations. Concrete pouring work should be as continuous as possible. For example, the upper and lower concrete pouring must be intermittent, and the long time interval (including the entire duration of transportation, pouring and intermittent) shall not exceed the regulations.
Retention and treatment of construction joints
If the concrete cannot be poured continuously due to technical reasons or limitations of equipment and manpower, and the intermittent time in the middle exceeds the allowable time, it shall be determined in advance to leave construction joints in appropriate positions. Because the bonding force between the old and new concrete is poor, it is a weak link in the component, so the construction joint should be left in the part where the structural stress (shear force) is small and easy to construct. Horizontal joints should be reserved for columns, and vertical joints should be reserved for beams and slabs.