61, why are there three lines in each production mix, and how should they be used?A: A theoretical mix ratio of behavior (that is, the water content of sand and stone is zero) is used by some stations. The production mix used by the two acts of dry days. The mix ratio used on rainy days and after ra

43. What is the impermeability of concrete?A: It refers to the concrete's resistance to pressure water infiltration. Both basement and reservoir are required to have good impermeability.44, impervious concrete commonly used impervious grade has a few?A: There are four commonly used impermeability gr

37, how to check the quality of concrete mold test?A: Use vernier caliper to measure the length, width and height of the test die, allowing error ≤0.5mm. With caliper back and 0.02 ~ 1mm stainless steel gauge with measuring four inner surface flatness, allow error ≤0.05㎜ (standard method is card 100

31, concrete mix main test which several performance?A: It mainly tests the workability, slump and gas content of the mixture. Workability is represented by cohesiveness, water retention, fluidity and comprehensive expression.(1) cohesiveness - by eye observation, when the slump is done, the test bo

19. What items should be inspected when fly ash enters the factory?A: The fineness and water requirement ratio of fly ash should be tested. The key item is water requirement ratio. If the fineness slightly exceeds the standard and the water requirement reaches the level II requirement, the ash can b

13. Why should continuous grain grade stones be preferred for pumping concrete?Answer: Because the void fraction of single grain size is larger than that of continuous grain size when the stone is quite large and the particle size is the same, the large void fraction should be filled with mortar. Th

1. What is commercial concrete?Answer: According to the requirements of the demander, concrete mix with cement, water, sand, stone, admixture and mineral admixture and other components according to a certain proportion, after metering and mixing in the mixing station, sold and transported to the dem

Polycarboxylic acid superplasticizer is a third generation of high-performance superplasticizer in modern engineering construction, which can improve the quality of construction projects and is a relatively satisfactory building material in engineering construction.It has a high water reduction, can