Question: What is the reason why it is easy to block the pipe when pumping concrete into the deep foundation pit with a tow pump? What measures should be taken?
Answer: When the depth of the deep foundation pit exceeds 5m, the concrete mixture in the inclined pipe section from the ground to the bottom of the pit is subjected to a large downward gravitational force, which causes the mixture to move downward, and the gas in it forms upward to the bend Air blockage. A 180 ° elbow can be installed at the lower end of the inclined pipe section to solve the pipe blocking problem; an exhaust valve can also be installed at the upper end of the lower elbow to solve the pipe blocking problem.
Question: If the pumped concrete is of low grade, is it difficult to beat? Because a batch of orders were received at the near station, it was a cushion. The C20 was used. The pump driver reflected that it was not easy to hit. When I went to the construction site to see it, I found that the pump was very difficult to play. Because of the small amount of cement used in concrete, the cohesion is not very small. In addition to the use of fine stones, there are too many stones, so it is not easy to beat?
Answer: It may be that your mix ratio design is not reasonable. The low-strength pumped concrete mix ratio design should use "double-mixed" mineral materials, that is, a large amount of slag powder and fly ash are mixed at the same time to make the concrete powder Relatively large, which is particularly advantageous for pumpability.