In case of bleeding of fresh concrete in commercial concrete mixing plant, the cause shall be found out in time. If it is not the adaptability of admixtures and cementitious materials, the mixing proportion of coarse aggregate can be adjusted to the best gradation, and the fixed mixing proportion must not be applied
When the site slump exceeds the limit of the designed slump of the mix proportion, the reason shall be analyzed in time, the water content of sand and gravel shall be measured again, and the mix proportion shall be corrected. If there is no error in the measured and calculated water content, the dosage of water reducer can be increased or reduced by 0.05 ~ 0.1%
When the sand rate of concrete produced by commercial mixing plant is too large or too small, the reason shall be found out in time, and the sand rate shall be properly adjusted to ± 1%. If the above methods can not solve the problem of concrete produced by commercial mixing plant, the production of concrete shall be stopped immediately, professional maintenance personnel shall be found for maintenance, and effective measures shall be taken in time, Avoid other quality problems
The removal sequence of concrete formwork is generally non load-bearing formwork first, and then load-bearing formwork; First the side plate and then the bottom plate. Follow the principle of removing after supporting, removing non load-bearing parts first, and then removing load-bearing parts from top to bottom. During formwork removal, it is strictly prohibited to smash and pry with sledgehammer and crowbar.
When removing the formwork, the staff shall stand in a safe place to avoid accidents. After all the formwork in this section are removed, the formwork, accessories and supports can be transported out of the stack. The removed concrete formwork and accessories shall not be thrown away. They shall be received and delivered by someone, stacked at the designated place, and cleaned, repaired and painted with isolation agent in time for use. Self loading mixer