What factors will affect the setting speed of concrete?

Concrete setting time is divided into initial and final setting. Initial setting refers to the time that concrete undergoes from adding water to losing plasticity, that is, the time limit of construction operation. The setting time of concrete is similar to that of cement, but there are some differences because of the addition of aggregate, the change of water cement ratio and the application of additives. Therefore, it is necessary to introduce the factors that affect the consolidation time of concrete.

 

The factors affecting the consolidation time of concrete are analyzed by experts in the prospecting concrete mixing station.

 

1. air temperature: the higher the air temperature, the quicker the consolidation time.

 

2. Concrete labeling: When other premises are the same, the consolidation time of concrete is shortened with the increase of labeling.

 

3. slump: general slump increase and consolidation time can be extended.

 

4. maintenance condition: concrete in water is longer than that in air. Generally, the initial setting time is about 8H when the water temperature in the well is 17 C and the underwater concrete is labeled 20. When the diameter of the pile is larger, the pile body is longer, the required pouring time is longer, Tianjin Dagang asphalt mixing station can not be completed in the initial setting time, the retarder can be mixed into the first batch of concrete. The dosage is determined according to the type of cement and the performance of retarder.

 

5. Cement varieties: cement with mixtures has a longer consolidation time, such as slag cement than the same label of ordinary cement consolidation time, low label cement higher label cement consolidation time.

 

6. admixture: adding a small amount of retarder can extend the initial setting time and final setting time of concrete.

 

7. the ratio of ash to water: when the ratio of ash to water increases, the consolidation time extends.