Operating conditions.
1. Concrete layer formwork, steel bar, top embedded parts and pipes have all been installed, which meet the design requirements after inspection, and the concealment and pre-inspection procedures have been handled.
2. Shelves and. After the concrete pouring is completed and passed the inspection.
3. Cement, sand, stone and admixture meet the requirements of relevant standards after inspection, and the laboratory has issued a notice of concrete mixture ratio.
4. The scale (or automatic feeding system) has been tested accurately, and the vibrator (rod) has passed the trial operation.
5. The foreman has conducted comprehensive construction technical training for the operation team according to the construction scheme, and the application for concrete pouring has been approved.
Matters needing attention
1. When concrete is poured into formwork, formwork or steel skeleton shall not be dumped centrally. When the pouring height is greater than 2M, the string tube and chute should be used for discharging, and the free falling height from the discharging nozzle to the pouring layer should not be greater than1.5m.
2. Concrete must be poured within 5 hours (from the start of the train). In order to prevent cold joint (cold joint: refers to the construction quality joint formed when the pouring time interval of upper and lower concrete exceeds the initial setting time), the concrete pouring time for two times shall not exceed 1.5 hours.
3. When pouring, the vibrating duration should make the concrete surface appear laitance, no bubbles and no sinking. The insertion points of vibrators are arranged evenly in plum blossom shape, and move in the order of determinant, and the distance of moving position should not be greater than 40CM. Make sure there is no vibration leakage, but no vibration.