Why meet for mixing concrete pumps concrete pumping of concrete pumpability

Mixing concrete pump in the pumping of concrete pump if you do not meet the requirements of the pumpability of concrete, is likely to cause obstruction, will also reduce the rate of concrete quality assurance. So, should meet the normal strength and durability requirements, also suitable for pipeline transportation, no segregation, no bleeding, no pipe blockage and cohesiveness of good features.

Concrete pump try pumping need to confirm the mixture ratio of pumping concrete.

1, the aggregate option: maximum size of coarse aggregate ratio of the diameter of delivery tube shall be: pumping height in 50m, when the gravel should not be greater than 1:3, gravel should not be more than 1:2.5; when pumping height in 50~100m, should be in the 1:3~1:4 range; 100m pumping height above, should be between 1:4~1:5. Content should not be greater than the 10% flaky particles. Rate of pumping concrete with sand, should be 38%~45%. Fine aggregate sand should be used, through the 0.315m hole of sand should not be less than 15%.

2, the slump can be selected depending on the pumping height. If pumping height is 30 in turn below, 30~60, 60~100, 100 or above (m), then the slump (mm) then the 100~140 and the 140~160, 160~180, and 180~200.

3, pumping the water/cement ratio of the concrete should be (0.4~0.6): 1.

4, the minimum cement content of 300kg/M3.

Concrete pump in the open pump after pump appropriate amount of water, wet concrete Hopper, tank and pipeline direct contact with concrete spot. After pumping the water and then pump slurry; pumping of 1:2 cement mortar; pump other than coarse aggregate distribution and ratio of cement mortar. Lubrication of the cement paste or mortar shall be dispersed fabric, not pouring concentrated in the same place.

When mixing concrete pump in the pump should be in a State of slow, running at a constant speed, then gradually speed up. Should also observe the pressure of concrete pumps and systems work, the pumping system works properly behind the normal speed. And the pump as far as possible continuous concrete cylinder piston should be maintained with the greatest running, in order to provide maximum efficiency of concrete pump and concrete cylinder wear uniform in length. As a result of pressure and instability, high oil temperature. Duct when obvious phenomena such as vibrations and pumping hard, forcibly pumped, should immediately identify the reason shall be excluded. First use mallets duct bend. Conical tubes and other parts, and the slow-speed pump or the pump, to prevent clogging.

Meet the pumpability of concrete pumping characteristics of the good. Construction site according to the technical requirements for design and construction unit field, in strict accordance with the relevant provisions of the program meets the requirements of design and construction technology of pump concrete, provide important protection for concrete structure construction quality.