Concrete uniformity is influenced by many variables: the water-cement proportion of concrete, aggregate grading and homes, time, temperature level, concrete features as well as admixture, but the major influencing aspect is the water-cement ratio of concrete. Depression straight reflects the dimension of water cement proportion as well as the pumping efficiency of concrete.
① Connection between downturn and pumping pressure. The slump size of concrete reflects the high quality of its liquidity energy, so the communicating resistance of concrete reductions with the rise of depression, the smaller the downturn, the greater the pumping pressure.
② The downturn series of the pumping concrete and its effect on the pumping quantity efficiency. Average high-rise building pumping concrete downturn control in 60 ~ 180mm range, and also skyscraper concrete depression control in 180 ~ 200mm, the most effective, the suction result is the very best, the factor is:
- If slump is also little, it will boost the pumping stress and create pump wear, simple to create the pipeline plugging.
- When the downturn is too big, on the one hand, the concrete is easy to partition under the action of large stress, resulting in blocking the pipeline; on the other hand, it additionally influences the suction ability of the pump, making the concrete precipitate in the suction procedure, which is hard to pump. at the same time, it is easy to leak slurry as a result of the lax sealing of the distribution valve.
③ Assurance measures of concrete depression. Purely control the mix proportion of concrete; choose suitable admixtures; reduce the transport time of concrete before pumping; as well as guarantee the homogeneity of concrete.
To sum up, the evaluation of the downturn of the concrete, the major elements influencing the concrete mix ratio, identify the design principle of mix ratio, choose the rugged and fine aggregate as well as admixture, select the ideal concrete pump and pump pipeline, and also take reasonable layout, to fulfill the pumping requirements of skyscrapers, the project application result will certainly be great.
